Anatomy of a Fish Coloring Answer Key Updated
Anatomy of a Fish Coloring Answer Key
External Beefcake of Fishes
Anatomy is the study of an organism's structures. Fishes come in a various array of forms, many with special modifications. The shape, size, and structure of body parts allow different fishes to live in different environments or in different parts of the same environment. The external anatomy of a fish can reveal a smashing bargain about where and how it lives.
When describing the basic anatomy of an organism, it is useful to take some common terms to help with orientation. Just equally a map uses north, south, east, or west to assistance make up one's mind the location, orientation words are useful in describing beefcake. Tabular array 4.3 defines common anatomy terms, Fig. 4.18 shows their orientation on three different animals.
| Anatomy Word | ...of the organism |
|---|---|
| Anterior | The head end... |
| Posterior | The tail stop... |
| Dorsal | The back |
| Ventral | The forepart or belly |
| Lateral | The side or flank |
Scientists mensurate and draw the external features of fishes to identify species, appraise historic period and health, and learn well-nigh construction and function. Scientists work with a multifariousness of types of fishes to do this. They might use a fresh fish, or they may use photographs, scientific drawings, or other kinds of detailed images–fifty-fifty fish fossils.
One way to document details near a fish is gyotaku. Gyotaku (pronounced gee yo TAH koo) is a traditional Japanese method of printmaking, which uses the whole fish. This method can produce an accurate epitome of a fish (Fig. 4.19).
Gyotaku is a relatively new art course that developed in Japan, probably in the early- to mid-nineteenth century. Gyotaku means 'fish rubbing.' Gyotaku is valued from both a scientific and artistic perspective. The detail captured in gyotaku, especially in historical prints, is an important source of data for scientists who want to know the size and external features of fish in the past. The colour and creative arrangement of gyotaku prints made by skilled artists as well make them valuable pieces of art. The oldest known gyotaku print, made in 1862, is endemic by the Homma Museum in Sakata, Japan.
Action: Fish Printing for Form and Function
Use your ascertainment and investigation skills to investigate fish form and function by experimenting with ways of making gyotaku fish prints.
Trunk Form
Perches are the most mutual type of bony fishes. Equally a result, people often use the words perch-like to describe a generic fish shape. (Fig. 4.21 A). Fusiform is the scientific term used to describe the perch'due south streamlined, torpedo shaped body. Compressiform means laterally flattened (Fig. 4.21 B). Depressiform means dorso-ventrally flattened (Fig. four.21 C). Anguilliform means eel-similar (Fig. iv.21 D). Come across Table iv.4 for additional descriptions of fish body shapes.
Table 4.4. Fish form and function: body shape
| Diagram of Trunk | Description | Adjusted Function |
|---|---|---|
 | Anguiliform (eel shape) | Maneuvering in crevasses |
 | Fusiform (bullet, or torpedo shape) | Lowering frictional resistance in fast swimmers |
 | Depressiform (broad shape and flat top to bottom) | Lying on or below the surface of the sand |
 | Compressiform (tall, thin shape and apartment side to side) | Entering vertical crevices |
 | Vertically flattened shape that is somewhat depressiform (flat top to bottom) | Bottom heavy for sitting on the bottom, not casting a shadow |
 | Fusiform (bullet, or torpedo shape), which is also sometimes called perch like | General all-purpose shape |
 | Elongated shape that is somewhat anguiliform (eel shape) | Deadfall predators |
Images past Byron Inouye
Fish Fins
The first anatomical structures many people identify on a fish are the fins. In fact, "appendages, when present, as fins" is function of i of the scientific definitions of a fish. About fish have ii kinds of fins: median and paired.
Median fins are unmarried fins that run down the midline of the torso. The dorsal fin is a median fin located on the dorsal side of the fish. The anal fin and caudal fin are also median fins. Paired fins are arranged in pairs, like homo arms and legs. The pelvic and pectoral fins are both paired fins. (Table 4.v).
Table 4.5. Fish form and part: dorsal fin features
| DORSAL FIN DIAGRAM | Clarification | ADAPTED Office |
|---|---|---|
 | Spiny and soft-rayed dorsal fin. | Flared to make the fish expect bigger |
 | Tucked dorsal fin | Reduces drag in fast swimming fish |
 | Locking spiny dorsal fin | Locking fish into coral crevices |
 | Very long dorsal fin | Ophidian-like locomotion |
 | Three dorsal fins | Locomotion |
 | No dorsal fin | Snake-like locomotion |
Images past Byron Inouye
Median Fins
Median fins, similar the dorsal, anal, and caudal fins, can part similar the keel of a gunkhole and help in stabilization (Fig. 4.22 A). Median fins can also serve other purposes, similar protection in the lion fish (Fig. 4.22 B).
Caudal (Tail) Fin
The caudal fin is known commonly equally the tail fin (Table 4.6). Information technology is the primary bagginess used for locomotion in many fishes. The caudal fin is besides a median fin (Fig. four.22 A).
The caudal peduncle is the base of the caudal fin. Peduncle means stem, and the caudal peduncle is where the stiff swimming muscles of the tail are found. Together, the caudal fin acts like a "propeller" for the fish, and the caudal peduncle acts like a motor.
Table 4.6. Fish form and function: Caudal fin features
| Tail Diagram | Description | Adapted Part |
|---|---|---|
 | Rounded tail | Slow swimming, accelerating, and maneuvering |
 | Truncated (triangular) tail | Turning apace |
 | Lunate (moon shaped) tail | Continuous long altitude swimming |
 | Forked tail | Rapid swimming, somewhat sustained with bursts of speed |
 | Heteroceral (taller upper lobe) tail | Tiresome or rapid swimming with bursts of speed |
Images by Byron Inouye
Paired Fins
Fish have two sets of paired fins: pectoral and pelvic (Fig 4.25). The pectoral fins are vertical and are located on the sides of the fish, unremarkably merely past the operculum (Table 4.7). Pectoral fins are like to human artillery, which are found well-nigh the pectoral muscles. Many fish, such as reef fish like wrasses (Fig. iv.25 B), utilise their pectoral fins for locomotion.
Table 4.vii. Fish form and function: Pectoral fin features
| Pectoral Fin Diagram | Description | Adjusted Function |
|---|---|---|
 | Fringe-similar pectoral fins | Probing substrate |
 | Spiny pectoral fins | Propping on substrate |
 | Hand-similar pectoral fins | Crawling on substrate |
 | Wing-like pectoral fins | Soaring and swimming |
 | No pectoral fins | Snake-like swimming |
 | Normal size pectoral fins | Maneuvering |
Images by Byron Inouye
The pelvic fins sit down horizontally on the ventral side of the fish, past the pectoral fins (Table four.8). Pelvic fins are like to legs. Just like human legs, pelvic fins are associated with the pelvis of the fish.
Table 4.8. Fish class and office: Pelvic Fin Features
| Pelvic Fin Diagram | Description | Adapted Function |
|---|---|---|
 | Sucker-like pelvic fins | Grabbing rocks by sucktion |
 | Thickened rays on pelvic fins | Sitting on substrate |
 | Moderate sized pelvic fins | Locomotion |
Unique and Specialized Fins
Paired fins are about unremarkably used for maneuvering, like the oars on a rowboat. However, both the pectoral and pelvic fins can likewise be highly specialized like those of the flying fish (Fig. 4.26 A). Unique combinations of other fins tin also help fish to exist fifty-fifty more specialized, like the pectoral and anal fins of a box fish (Fig. 4.26 B; see Table 4.9) .
Table 4.9. Fish form and function: Combinations of Fins
| Fin Combination Diagram | Description | Adapted part |
|---|---|---|
 | Dorsal and anal fins | Modified to increase propulsion |
 | Pectoral and tail fins | Modified for soaring in air |
Spines and Rays
Scientists apply fins to assistance identify and classify fish species. In more than evolutionarily avant-garde fish, the fins are supported past bony structures: spines and soft rays. Spines are elementary, unbranched, structures. Soft rays are compound, segmented, and branched structures (Fig. iv.27).
The Oral fissure
The mouth is at the front, or anterior finish, of the fish. The mouth tin can reveal a lot about the fish's feeding habits (Table 4.10). The size, shape, and placement of the mouth, combined with the type of teeth, provide critical information about the feeding habits of a fish (Tabular array 4.11).
For example, a fish with a rima oris on the lesser of its caput often feeds by digging in the bottom sediment (Fig. 4.28 A). A fish with a oral fissure oriented upward unremarkably feeds in the water column, or fifty-fifty higher up the h2o (Fig. 4.28 B). When a fish has its mouth open, the front lip may slide down and out from the mouth. This sliding activeness of the mouth tin can assist the fish create a vacuum and quickly suck in a big mouthful of water, which hopefully also includes casualty!
Fig. 4.28. (A) A bottom facing oral cavity indicates bottom feeding preferences in the sturgeon. (B) An upward facing mouth shows the surface feeding adaptation of the arowana.
Table iv.x. Fish form and function: Oral cavity Features
| Mouth Diagram | Description | Adapted Part |
|---|---|---|
 | Jawless | Scavenging or parasitic behavior |
 | Tweezer-similar snout | Poking into crevices |
 | Suction tube | Slurping in casualty |
 | Large mouth | Swallowing big prey |
 | Beak-like teeth | Biting hard objects |
 | Tiny and turned upwardly | Capturing plankton |
Table 4.11. Fish form and function: Teeth Features
| Teeth Diagram | Clarification | Adapted Function |
|---|---|---|
 | Pointed | Stabbing |
 | Rummage-like | Scraping fabric off rocks |
 | Heavy and flat, molar similar | Grinding |
 | Fused like a beak | Scraping hard materials off rocks |
 | Incisor-similar | Cutting |
 | Broom-similar | Filtering |
 | Steak knife-like | Serrated for sawing |
Eyes
The eyes of fish resemble man eyes (Fig. four.29). At the front of each heart is a lens, held in place by a suspensory ligament. The lens focuses images of objects on the retina. To bring near and far objects into focus, the lens retractor muscle moves the lens back and forth.
The retina is a low-cal-sensitive membrane rich in fretfulness that connect to the optic lobes of the brain by optic fretfulness. When low-cal shines on the nerves of the retina, the optic nerves send impulses to the optic lobes. Because fish have no eyelids, their eyes are always open.
Some elasmobranchs, and most teleost fishes, have color vision. Some fishes tin besides see in ultraviolet (UV) light. UV vision is particularly useful for reef fishes. UV vision helps fishes in foraging, communication, and mate choice.
Elasmobranchs, and some teleosts, also have a tapetum lucidum. The tapetum lucidum is a shiny, cogitating structure that reflects calorie-free and helps vision in low low-cal situations. The tapetum lucidum is what makes the eyes of sharks and deep sea fish, likewise equally state mammals like cats and cows, polish at night.
Fish eyes are usually placed just dorsal of and above the rima oris. Just like the mouth of a fish, the size, shape, and position of the eyes can provide information virtually where a fish lives and what it feeds on. For case, fish predators often have optics facing forward in gild to provide better depth perception. Prey fish, on the other hand, often have eyes on the sides of their bodies. This gives them a larger field of view for avoiding predators. (Tabular array 4.12).
Table 4.12. Fish grade and function: Eye Features
| Middle Diagram | Clarification | Adapted Role |
|---|---|---|
 | Tiny eyes, head length approximately vi times longer than middle width | Receiving high intensity low-cal |
 | Large eyes, head length approximately 3 times longer than centre width | Receiving low intensity lite or spotting predators |
 | Boilerplate optics head length iii to five times longer than eye width | Receiving normal intensity low-cal |
 | Tubular eyes | Receiving depression light from above often in deep water |
 | Eyes on dorsal side of the fish | Seeing above |
Nostrils
The sense of smell is well developed in some fishes. Water circulates through openings in the head called nostrils. Unlike humans, fish nostrils are non continued to whatever air passages. Fish nostrils serve no function in respiration. They are completely sensory.
The largest part of a fish'due south brain is the olfactory lobe, which is responsible for the sense of smell. Aroma is the response to chemic molecules past nerve endings in the nostrils. Chemoreception is the scientific term for what nerve cells exercise to assistance an organism smell (see Table 4.xiii).
Sense of taste Receptors
Taste is another course of chemoreception. Fish tin can gustatory modality within their mouth. Many fishes, like goatfish and catfish, also have fleshy structures chosen barbels around the chin, mouth, and nostrils (see Tabular array 4.xiii and Fig. 4.30). In some fishes, these barbels are used for touch and chemoreception.
Fig. 4.xxx.
Not all barbels accept chemoreception. The barbels of some fish, like catfishes, are not equipped for chemical reception (Fig. four.30 B). Some fish also have fleshy tabs called cirri on the head (Fig. 4.30 C). Cirri are not sensory organs.
Table iv.13. Fish form and function: Chemosensory Adaptation and Camouflage
| Diagram | Description | Adjusted part |
|---|---|---|
 | Barbels | Probing for food in sand. Can discover chemicals for smelling and tasting (merely notation that non all fishes' barbels can notice chemicals—like catfish barbels are cannot gustation or olfactory property) |
 | Tubular nostrils | Detecting chemicals for smelling and tasting |
 | Cirri on head past eyes | Camouflage (although they resemble chemosensory organs, they do not respond to chemicals) |
Lateral line
Most fish have a structure called the lateral line that runs the length of the body—from but behind the caput to the caudal peduncle (Fig. 4.31). The lateral line is used to assistance fishes sense vibrations in the water. Vibrations can come up from prey, predators, other fishes in a school, or ecology obstacles.
Fig. 4.31.
The lateral line is actually a row of pocket-sized pits that contain special sensory hair cells (Fig. 4.32). These pilus cells motility in response to motility well-nigh the fish. The lateral line sense is useful in hunting prey, escaping predators, and schooling.
Fig. 4.32.
Ampullary receptors
Ampullary receptors are sense organs fabricated of jelly-filled pores that observe electricity. They can observe depression frequency alternate current (Air-conditioning) and direct current (DC). Ampullae detect electricity emitted by prey as well every bit the small electrical fields generated by a fish's own movement through the world's magnetic fields. Researchers recall that this may aid fishes use the Earth'southward magnetic field for navigation. Fishes that have ampullae include sharks, sturgeon, lungfish, and elephant fish. The ampullae of sharks are known equally Ampullae of Lorenzini—named for Stefano Lorenzini, who first described them in 1678(Fig. 4.33).
Fig iv.33. (A) Ampullae of Lorenzini in a shark's head (B) Ampullae of Lorenzini pores on the snout of a tiger shark
Some fishes can besides generate their own electric fields. These fishes have both ampullae type receptors and tuberous type receptors. The tuberous receptors are about sensitive to the electric organ belch of the fish itself, which is important for object detection. The tuberous blazon of receptor is usually deeper in the skin than ampullae.
Some fishes that produce electricity also utilise it for advice. Electric fishes communicate by generating an electric field that another fish tin can find. For example, elephant fishes use electric advice for identification, alert, submission, courtship, and schooling (Fig. 4.34).
Fig 4.34. The elephant fish use electrical impulses to communicate.
Ears
Audio travels well underwater, and hearing is important to most fishes. Fishes accept ii inner ears embedded in spaces in their skulls. The lower chambers, the sacculus and the lagena, detect sound vibrations. (Run across Fig. four.35.)
Each ear chamber contains an otolith and is lined with sensory hairs. Otoliths are small, stone-like basic (See Fig. 4.36). They float in the fluid that fills the ear chambers. Otoliths lightly touch the sensory hair cells, which are sensitive to sound and movement.
Fig. iv.36. (A) Otolith (ear bone) of an American barrelfish (B) A pair of otoliths from a 160lb viii-banded grouper
Like the otoliths in human being ears, otoliths in fishes help with hearing and with balance. When a fish changes position, the otoliths bump the pilus cells in the ampullae. The ampullae are bulges in the semicircular canals of the ears (Fig four.36). When a fish rolls right or left, tail up or tail down, the liquids and otoliths push button against the hairlike nerve endings lining the canal, sending messages to the fish'southward brain.
Some fishes also use other organs to help in hearing. For example, the gas bladder changes volume in response to audio waves. Some fishes can detect these changes in gas bladder volume and use them to interpret sounds.
Gills and Oxygen Exchange
Most mammals get oxygen from the air, only most fishes become oxygen from the water. To get oxygen from the h2o, fish must pass h2o over their gills. Gills are composed of a gill arch, gill filaments, and gill rakers (run across Fig. iv.37). In many fishes the gill arch is a hard structure that supports the gill filaments. The gill filaments are soft with lots of blood vessels to blot oxygen from the water.
Fig. 4.37. (A) A bony fish with the operculum held open to show the gills (B) A unmarried gill removed from a bony fish (C) A drawing of a gill showing gill filaments (oxygen absorption), gill arch (supporting structure), and gill rakers (comb like structure for filtering).
As water passes through a fish's oral fissure, over the gills, and back into the environment, oxygen and carbon dioxide are exchanged. Some fishes, like tunas, need to continuously swim to become oxygen from the water. Other fishes, like wrasses, can laissez passer h2o over their gills by pumping it. This enables wrasses to remain motionless and still go oxygen.
Fishes get both oxygen and food from water. To become oxygen, water needs to move toward the gills. Merely, to get energy from food, the food needs to move down into the fish'due south stomach. The gill rakers are comb-like structures that filter food from the h2o before it heads to the gills. This keeps food particles inside the fish'due south mouth and lets water motion out toward the gills.
The construction of a fish's gill rakers indicates something about its diet. Fish that eat small casualty like plankton tend to have many long, thin gill rakers to filter very small prey from the water equally it passes from the oral cavity to the gills. On the other hand, fish that consume large prey tend to have more widely spaced gill rakers, because the gill rakers practise not need to catch tiny particles.
The Operculum is the bony plate that covers fishes' gills. In chimeras and bony fishes, the operculum covers the posterior end of the caput, which protects the gill openings. The bony operculum ofttimes has some other bony flap, called the preoperculum, overlaying it (Fig. four.30). Some fishes also have a strong spine, or spines, that project dorsum from the preoperculum or operculum. These spines are usually used for protection.
Sharks and rays accept open, naked gills (see Table 4.fourteen), meaning that they are non covered past an operculum. Their classification name, elasmobranch, actually means naked gill. Most elasmobranchs have five gill openings—exceptions include the six gill and seven gill shark.
Tabular array 4.14. Fish form and part: Gills
| GILL DIAGRAM | DESCRIPTION | ADAPTED Function |
|---|---|---|
 | Elasmobranchs accept naked gills | Piece of cake water flow |
 | Operculum covers gills | Gill protection |
 | Preoperculum and operculum spines | Armor and protection |
Fig. four.38. (A) A semicircle angelfish (Pomacanthus semicirculatus) with vivid blue highlight color on the preoperculum, preoperculum spine, and operculum (B) A dog snapper (Neomaenis jocu) with preoperculum, operculum, and operculum spine labeled.
The buccal pump is what fish utilise to move water over their gills when they are not swimming. The buccal pump has 2 parts: the rima oris and the operculum. During the first stage of pumping, both opercula close, and the mouth opens. Water then enters through the mouth. Side by side, the fish closes its mouth and opens its opercula and so that water moves over the gills, which remove oxygen from the h2o. Some fishes besides utilise the buccal pump as part of their feeding strategy by filtering out small organisms living in the water as they pump water (Fig. 4.39). As water passes through, the gill rakers help to trap plankton from the water.
Fig. 4.39. Some fishes feed by filtering out through their buccal pump such as this whale shark, which feeds on plankton
Pores
A pore is a pocket-sized opening in the pare. A typical fish has anal, genital, and urinary pores located anterior of the anal fin. The anal pore is where carrion exits the fish body. The anus is the largest and almost anterior of the pores (Fig. 4.twoscore A).
The genital pore is where eggs or sperm are released. The urinary pore is where urine exits the body. Often the genital and urinary pore are combined into a single urogenital pore. These pores are situated on a pocket-size papilla, or bump, just backside the anus (Fig. 4.forty B).
Most fishes reproduce externally, meaning that the sperm and eggs meet outside their bodies. However, some fishes reproduce internally. The females of these fishes often accept a genital pore that is modified for internal fertilization.
Body Coverings
One definition of a fish includes "body unremarkably covered with scales." Except for some parts of the caput and fins, the bodies of many fishes are covered with overlapping scales (Fig. 4.41). Scales generally serve to protect the fish's skin.
Unlike fishes have different types of scales. These different types of scales are made of unlike types of tissue (Fig. 4.42 and Table 4.15). Types of scales as well stand for to evolutionary relationships (Fig. 4.9).
Placoid scales are found in the sharks and rays (Fig. 4.42 A). Placoid scales are made of a flattened base of operations with a spine protruding towards the rear of the fish. These scales are often called dermal denticles because they are made from dentin and enamel, which is like to the fabric teeth are fabricated of.
Ganoid scales are flat and practise not overlap very much on the body of the fish (Fig. 4.42 B). They are found on gars and paddlefishes. In the sturgeon, ganoid scales are modified into body plates called scutes.
Cycloid and Ctenoid scales are establish in the vast majority of bony fishes (Figs 4.42 C and 4.42 D). These types of scales can overlap like shingles on a roof, which gives more flexibility to the fish. These scales as well form growth rings like trees that can be used for determining age.
Ctenoid scales are different than cycloid scales in that cycloid scales tend to be more oval in shape. Ctenoid scales are more than mollusk shaped and have spines over one border. Cycloid scales are institute on fishes such equally eels, goldfish, and trout. Ctenoid scales are institute on fishes like perches, wrasses, and parrotfish. Some flatfishes, similar flounder, have both cycloid and ctenoid scales.
Tabular array four.15. Fish class and function: Scale Features
| Scale Diagram | Clarification | Adapted Role |
|---|---|---|
 | Spines | Protection from predators |
 | Blades | Protection and defense |
 | Scutes (or keel; not shown) | Cuts through water, streamlines swimming |
 | Many large scales | Protection |
 | No scales | Burrowing |
 | Leathery scales | Protection |
 | Bony armor scutes | Protection from predators |
 | Rough scales | Protection from parasites and swimming locomotion |
 | Regular scales | Protection |
Scale size varies greatly among species, and not all fishes have scales. Some fishes, like some rays, eels, and blennies, do not take any scales. This is probably considering these fishes spend a lot of time rubbing on the sand or in rocks. If they had scales, the scales would likely rub off. At the other extreme, some fishes take scales modified into bony plates, such as on a sturgeon and pinecone fish (Fig. 4.43 A). Other fish have scales modified into spines for protection, like the porcupine fish (Fig. four.43 B).
Activity: Observing Fish Scales
Employ your observation and investigation skills to investigate different types of fish scales.
Additional Modifications
Fishes are very various, and at that place are examples of farthermost body modifications in many unlike groups of fishes (see Tabular array iv.16). For instance, some fishes, like angler fish, have lures to attract prey. Others, similar lionfish, accept poisonous substance sacs to protect them from predators.
Table 4.16. Fish course and office: Other Modifications
| Diagram | Description | Adapted Function |
|---|---|---|
 | Lures | Attracting prey |
 | Toxicant sacs at base of spines | Protection |
Color
The colour of fishes is very diverse and depends on where a fish lives. Colour can be used every bit camouflage. Colour also plays a function in finding mates, in advertising services like cleaning, in attracting casualty, and in warning other fishes of danger (come across Table iv.17).
Tunas, barracuda, sharks, and other fishes that live in the open up ocean are oftentimes silvery or deep bluish in colour. These fishes too have a body coloring design called counter shading. Counter shading ways dark on the dorsal, or top, surface and light on the ventral, or belly side. Countershading helps to camouflage fishes by matching the night, deep h2o when viewed from higher up and matching the light, surface water, when viewed from below (Fig. 4.44 B).
Fig. 4.44. (A) blue silverish colour in Heller's barracuda (B) Countershading in a grey reef shark
Nearer to shore, many fishes have likewise evolved to exist inconspicuous in their surroundings. Kelpfish have adult both colors and a body shape that helps them blend in with the seaweed that they live in. Reef fish oftentimes look like coral. Fishes that hide in the sand, similar blennies, apartment fish, and flounder, are often a speckled sandy color (Fig. 4.45 B).
Fig. 4.45. (A) A leafy seadragon hiding in kelp (B) A blenny hiding in coral (C) A 3-spot flounder hiding in sand
Many brightly colored fishes that alive in coral reef habitats besides use their color, stripes, and spots as camouflage (Fig. 4.46). This is partly considering wavelengths of low-cal, and therefore color, announced different under h2o and modify with depth and water color. Water absorbs light. Thus, the amount of light decreases with increasing depth.
Red color, for example, fades out very fast with increasing depth. Fishes with reddish color, similar soldierfish (Fig. iv.46 A), are really invisible at night and in deep waters. Yellow and blueish colors, on the other hand, alloy in with the reef color, as well providing camouflage from predators (Fig. 4.46 B). Even stripes and spots can preclude an private fish from continuing out, making information technology harder for a predator to strike (Fig. 4.46 C).
Fig. 4.46. (A) Soldierfish (B) blueish and yellow Hawaiian cleaner wrasse (C) school of captive tang and whitebar surgeonfish
In addition to colors visible to humans, fish besides employ ultraviolet (UV) light colors for camouflage and communication. Some fishes can see using UV lite, and and so they use UV colors to identify each other and to avoid predators. Many reef fish can also glimmer their colors on and off to flash letters (Fig. four.47). Peel cells called chromatophores allow fish and other animals to quickly change skin color.
Table 4.17
| Body Colour Diagram Example | Picture Example | Description | Adapted Function |
|---|---|---|---|
 |  | Both sexes brightly colored | A warning—not good to eat |
 |  | Brightly colored areas around the spine on the caudal peduncle area. The spine is used in defense. | Warning |
 |  | Mottled | Camouflage |
 |  | Dark on elevation, lighter on bottom | Camouflage in midwater |
 |  | Dark all over | Cover-up in dark areas |
 |  | Red all over | Camouflage in dark areas |
 |  | Lite all over | Camouflage in light areas |
 |  | Eyespots | Leading predator away from head |
 |  | Brightly colored | Camouflage or communication |
Internal Fish Anatomy and the Part of Fish Organ Systems
Living things are composed of cells. Cells often become specialized to perform certain functions. For example, muscle cells contract, nerve cells transmit impulses, and gland cells produce chemicals. A tissue is a group of similar cells performing a similar function (Fig. 4.48). At that place are many kinds of tissues—bone, cartilage, blood, fatty, tendon, skin, and scales.
An organ is a group of different kinds of tissues working together to perform a specific function (Fig. 4.48). The stomach is an example of an organ made of several types of tissues.
• Muscle tissue, in the wall of the stomach, contracts to churn and mix food.
• Glandular tissue, in the inner lining of the stomach, secretes digestive chemicals (enzymes).
• Nervus tissue, in the wall of the stomach, coordinates mixing and digesting activities.
An organ arrangement is a group of organs that together perform a role for the body. The digestive system, for case, consists of organs such as the mouth, the tum, and the intestine (Fig. four.48). These organs piece of work together to break downwards food and provide nutrients to the body.
An organism is an unabridged living thing with all its organ systems (Fig. 4.48). A circuitous organism like a fish has digestive, nervous, sensory, reproductive, and many other systems. Fish consist of interacting groups of organ systems that together enable a fish to part.
Integumentary System
The integumentary system is commonly called the skin. It consists of two layers, the epidermis, or outer layer, and the dermis, or inner layer. Beneath these are the muscles and other tissues that the skin covers (Fig. 4.49).
The epidermis is the top layer of the integumentary organisation. It is made of several sheets of cells that cover the scales. As the cells historic period, new cells growing underneath push older cells toward the outer surface.
In the epidermis of most fishes are cells that produce mucus, a slippery material like runny gelatin, that helps the fish slide through the h2o. The mucus wears off daily, carrying abroad microscopic organisms and other irritants that might damage the fish. The smell typical of most fish comes from chemicals in the fungus.
In their epidermis, fishes have cells containing pigment grains that give the fish its color. Some fish tin change colour past expanding or contracting pigment cells. The changes are controlled by hormones that are produced by the endocrine system and regulated past the nervous system.
The lower layer of the integumentary system contains blood vessels, nerves for sensing bear on and vibration, and connective tissue made of strong fibers. A special layer of dermal cells secretes chemicals to produce scales, which grow larger as the fish grows. Most fish have covering scales that protect them from impairment when they crash-land into things or are attacked. Equally the scales grow, they grade concentric rings in some fishes. These growth rings can be used to make up one's mind a fish'southward age. A few fish, such as catfish, have no scales.
Skeletal and Muscular Systems
The skeletal arrangement supports the soft tissues and organs of the fish (Fig. 4.50). The skeleton too protects organs and gives the body of the fish its basic shape. The many bones of the skull form a rigid box that protects the brain. Holes, hinges, and pockets in the skull allow room for the nostrils, mouth, and eyes.
Fig. iv.50. (A) The skeleton of a cod fish (B) A drawing of a fish skeletal system
The vertebral column, or backbone, is not a solid rod. The backbone is really a cord of small bones chosen vertebrae. Encounter Fig. 4.51. Each vertebra has a small hole in it. Together, the small holes in the vertebrae class a culvert through which the spinal cord passes. The vertebrae bones protect the spinal cord. Spaces between the vertebrae allow the backbone to bend and nerves to attain the tissues and organs of the body. Rib basic protect the body cavity. Additional bones back up the spines and rays.
Fig. 4.51. (A) A photograph of the vertebrae of a minor fish (B) A drawing of a fish skeleton vertebrae viewed from the front, showing rib and tail sections
Muscles are tissues that contract to shorten and relax to lengthen. Fish move by contracting and relaxing their muscles. Like humans, fish have three types of muscles: skeletal muscles, shine muscles, and heart muscles.
The muscles and bones of a fish piece of work together. Skeletal muscles use bones every bit levers to movement the trunk. Tendons are strong connective tissues that adhere muscle to bone. When muscle cells are stimulated, they contract and shorten, which pulls on tendons to move bones.
Skeletal muscles are voluntary, significant that they motility just when the thinking part of the brain signals them to move. To swim, fish must contract and relax their skeletal muscles, just equally humans do when they learn to walk. Almost of a fish'south body is fabricated of layers of skeletal muscle. These layers are arranged in Westward-shaped bands from abdomen to dorsum (Fig. 4.52). This network of muscles is vertical and interlocking, which allows the fish to move the body back and along in a smooth, undulating move. Such motion would not exist possible if the muscles ran horizontally along the length of the body, from head to tail.
Fig. 4.52. (A) Side view of salmon skeletal muscle (B) Cartoon of skeletal muscle pattern in a fish
A fish swims past alternately contracting muscles on either side of its body (See Fig. 4.53 B). Swimming begins when the muscles on one side of the body contract, pulling the caudal fin toward that side. The sideways movement of the caudal fin pushes the fish forrard. Then the muscles on the opposite side of the body contract, and the caudal fin moves toward the other side of the trunk.
Fig. iv.53. (A) Sardines swim by contracting their tail muscles (B) A drawing contrasting a typical fish swimming movement with the move of a typical human swimming with dive fins.
Skeletal muscles are also attached to basic that move the fish'southward paired fins. Fishes with broad pectoral fins, like wrasses, swim by flapping their pectoral fins. Other fishes, like fast-pond tunas, movement mostly with their caudal fin merely apply long, sparse pectoral fins for steering.
Skeletal muscles as well move dorsal fins. Faster-swimming fishes reduce h2o drag by tucking in their dorsal fins while swimming. Slower-swimming reef fishes have larger dorsal fins, which they sometimes flare to protect themselves in encounters with other fish.
Smooth muscles move internal organs of the trunk and line tubes such every bit the intestinal tract and claret vessels. Smooth muscles are involuntary; they move without signals from the thinking office of the brain. For example, smooth muscles automatically contract and relax to push food through the digestive tract from the mouth to the anus. Other shine muscles control the menstruum of blood and other body fluids and motility in the urogenital tract.
Heart muscles are also involuntary. However, the construction of centre muscle cells is different from involuntary smooth muscles, and so these ii muscle types are given divide names. Eye muscles pump claret through the blood vessels past rhythmically contracting and relaxing.
Respiratory Organisation
The respiratory organisation takes oxygen (O2) into the body and passes carbon dioxide (CO2) out of the body. Oxygen is essential to fish's digestion because information technology combines with nutrient molecules to release free energy for the fish's needs.
The respiratory organs in fish are gills. Each gill has many gill filaments, which contain a network of tiny claret vessels called capillaries (Fig. four.54). The gill cover (also called the operculum) is the body surface that covers the gills. The gill rakers filter nutrient from the water every bit water passes out to the gills.
Fig. iv.54. (A) Exposed fish gills every bit viewed from the ventral, or belly side, of the head (B) A drawing of a gill filament with a gill raker and the gill arch labeled
Water moves over the gills in a pumping activity with ii steps (Fig. iv.55). In the first stride, the mouth opens, the gill covers close, and the fish brings water into its mouth. In the second pace, the rima oris closes, the gill covers open up, and water passes out of the fish. This action is called buccal pumping and is named for the cheek muscles that pull h2o into the mouth and over the gills.
Some fish too use ram ventilation to move water over their gills. When pond fast, fish like sharks and tunas open up both their mouths and gill openings to permit water pass continuously through their gills. They do not demand to open and close their rima oris because h2o is pushed over their gills by their pond action.
Equally water passes over the gills, carbon dioxide in the blood passes into the water through the capillaries of the gill filaments. The same gill filaments permit dissolved oxygen from the h2o to laissez passer into the blood, which then carries it throughout the body.
Fig. iv.55. Movement of h2o past the gills
Buoyancy
Buoyancy refers to whether something volition float or sink. Some fishes take a gas bladder that helps command their buoyancy. The gas bladder is a special, gas filled chamber in a fish'due south body cavity. It lies but below the kidneys.
The gas bladder is often called the swim bladder because it regulates buoyancy past making the fish's density equal to the density of the surrounding water. The average density of seawater is one.026 g/mL, merely the density of fish flesh and basic is nearly one.076 thou/mL. This ways that a typical fish is denser than seawater and would naturally sink. The density of the gas bladder, on the other manus, is less dumbo than seawater. The low density of the gas bladder helps the fish float (Fig iv.56).
Fig iv.56. (A) The position of the gas bladder (swim bladder) in a bleak (Alburnoides bipunctatus) (B) Gas bladder from a Ruddy fish (Scardinius erythrophthalmus)
The gas bladder has a depression density because it is filled mostly with oxygen and nitrogen gases. The gas bladder acts similar an inflatable airship inside the fish. The gas bladder reduces the density of the fish'south trunk until it is the same as the density of seawater. This helps the fish float within the water column.
In many groups of fishes (similar herring, freeway, catfish, eels), an open up tube connects the gas bladder to the digestive tract. This allows the fish to adjust gas content in the bladder by swallowing and expelling air through their mouth. Other kinds of fishes (similar perches, snappers, groupers) have a gas gland that bubbles gasses into and out of the bloodstream to inflate and deflate the gas bladder.
Force per unit area increases with increasing water depth because the water higher up pushes down on the water (and animals) below. When a fish swims into deeper water, its gas float gets smaller considering of the increment in h2o force per unit area. Thus, as a fish goes deeper, information technology must add gas to its gas bladder to maintain neutral buoyancy. When a fish swims into shallow water, its gas bladder expands because the pressure level of water surrounding the fish decreases. Thus, as it moves into shallower water, the fish must absorb gas from the gas float to maintain neutral buoyancy.
Because gases motion slowly in and out of the gas bladder, fish caught at great depths are oftentimes bloated when they are brought to the surface speedily. The gas in the gas bladder expands when the fish moves from the high pressure of deep water to the lower pressure level at the surface. A fish pulled quickly to the surface cannot absorb the gases fast enough, and the sudden expansion of the gas bladder tin can injure the fish (Fig. 4.57).
To keep the fish alive, collectors must bring fish to the surface slowly to let the fish's body blot the gases from the gas bladder. At that place are also methods for releasing a fish with recompression in order to assistance it recover from gas expansion as a result of being brought quickly to the surface (Fig. 4.58).
Some fishes, such as grunts and toadfish, can utilise their gas bladder to produce sound. Muscles in the wall of the float contract chop-chop, producing a low-frequency (depression-pitch) audio that is resonated and amplified in the bladder. Other fishes, like the lungfish, also employ the gas bladder as an accessory respiratory organ or "lung" when they crawl on land.
Fishes that have no gas float are always denser than the surrounding water, and so they sink if they finish swimming. Sharks, for example, must continue swimming to stay afloat. They utilize their tails and pectoral fins similar airplane wings, adjusting the corporeality of lift to control the depth of their pond. Many bottom-dwelling fishes also lack gas bladders because they have no real need from them.
Circulatory System
The circulatory system is a transportation arrangement for trunk fluids. The circulatory arrangement brings nutrients to cells and carries waste matter away from cells. Claret is a fluid that consists of plasma (the liquid part) and claret cells. Plasma contains water, carbon dioxide (CO2), hormones, nutrients, wastes, and other molecules. Blood cells are of two main types: reddish and white.
Ruby-red blood cells carry oxygen (O2) from the gills to other cells in the body. In red cells, special molecules that combine chemically with oxygen can pick up and release oxygen, depending on the surrounding environment. These molecules, called hemoglobin, contain iron atoms. When hemoglobin combines with oxygen, it turns vivid red. When hemoglobin releases its oxygen, information technology turns a very nighttime red.
White blood cells fight disease. They ofttimes concentrate effectually infected wounds, killing bacteria and transporting wastes away from the wound. Dead cells in a wound class pus, which white blood cells help to eliminate.
A network of tubes called arteries, capillaries, and veins connects the heart with all parts of the body (Fig. 4.59). The arteries carry blood from the heart to the capillaries. The capillaries, microscopic in size and very numerous, have thin walls through which nutrient molecules can move. The molecules move through the walls of the capillaries and into the fluids around the tissues. The veins comport blood from the capillaries back to the heart.
The heart pumps blood to all parts of the body. The fish center has 1 ventricle and one atrium. In comparison, the human being heart has two separate ventricles and two divide atria. In the fish heart, there are besides two other chambers: the sinus venosus (before the ventricle) and the bulbus arteriosus (after the atrium). (Come across Fig. four.60.)
When the heart muscle contracts, it forces blood into the arteries. Valves between the chambers let the blood to flow in only ane management. Blood that is low in oxygen and high in carbon dioxide is pumped to the gills, where it releases carbon dioxide and picks up more than oxygen through capillaries in the gill filaments. The claret, now rich in oxygen, flows through branching arteries to the brain, digestive system, and other tissues and organs.
As information technology passes through the digestive system, the blood absorbs nutrients and distributes them through the body. As it passes through each tissue and organ, some of the blood plasma passes through capillaries and flows effectually the cells. Oxygen and nutrient molecules move from the plasma into the cells. Carbon dioxide and waste material products move from the cells into the plasma. The plasma then passes back into the capillaries and carries waste abroad.
Another network of tubes, called lymph ducts, picks up the liquid that passes out of the capillaries and collects in parts of the fish's body. The lymph ducts return this liquid (called lymph) to the veins.
Digestive and Excretory Arrangement
A fish's digestive and excretory arrangement includes the structures and organs that bring food into the body, pause food down into usable substances organism, and remove unused food. The digestive system begins with the rima oris and teeth, which trap nutrient and assistance ship information technology on to the tum and intestine for digestion. Undigested food and waste leaves the body through the anus (Fig. four.61).
The urinary portion of the excretory system as well removes waste produced by the body. Its chief organs are the kidneys, which are a pair of long, dark-red organs nether the vertebrae. The kidneys filter small molecules from the blood. Subsequently filtering, usable materials such as sugars, salts, and water are captivated back into the blood. The remaining waste matter products laissez passer from the kidneys downwards the urinary tubes, to the float, and out through an opening behind the anus, chosen the urogenital opening. This is the same opening through which materials from the reproductive organisation (eggs from the ovaries or sperm from the testes) laissez passer.
The gills are also office of the excretory system. Blood carries waste matter products and excess salts to the gill filaments. Carbon dioxide (CO2) and ammonia are excreted by the gills. Fish living in seawater and brackish water likewise excrete excess salt from their gills.
The liver also removes wastes from the blood. The liver cleans blood subsequently it has picked up digested products from the intestine. Wastes are converted into bile and stored in the gall float, where they wait to exist poured dorsum into the digestive tract to aid in digestion (Fig. 4.61).
Osmosis is the passive motility of water across cell membranes. If two fluids have different salinities, h2o volition cross the prison cell membrane to balance the salinity on both sides. This means that the excretory system is affected by where a fish lives.
Freshwater fishes accept trunk tissues that are saltier than the surrounding water. Thus, water constantly enters the body through the gills and body cavities. Freshwater fishes must urinate frequently to rid themselves of this excess h2o.
Saltwater fishes, by contrast, are surrounded by water that is saltier than their actual fluids. H2o is always leaving their bodies. To preclude dehydration, saltwater fishes drink constantly, and excrete small amounts of very concentrated urine. Special salt glands in the gills also help eliminate the common salt from the water drank by the fish.
The nature of the online format of this curriculum allows us to continuously add content and activities. You take reached a section of Exploring Our Fluid Earth that is still under construction. Go along visiting for new additions!
Anatomy of a Fish Coloring Answer Key
Posted by: chavezvournet.blogspot.com
0 Response to "Anatomy of a Fish Coloring Answer Key Updated"
Post a Comment