Module 20 Flashcards

Question

Filter-feeding vertebrates

Answer 1

Tend to have closely spaced baleen plates or gill rakers

Answer 2

The fused teeth of parrot fishes allow them to remove algae from reefs – this would otherwise outcompete corals

Answer 3

Tend to have short blunt stouts Narrow gape Jaws lined with close-set teeth for cropping, scraping, excavating, or combing algae Eyes are set on either side of their head to look for food

Answer 4

Some lack teeth or have very small teeth Swallow their prey whole Trend to have robust gill rakers that often bear teeth – these trap prey in the buccopharyngeal cavity so that they can be swallowed

Answer 5

Used to grasp and puncture prey Prey is then manipulated to be swallowed headfirst Occurs in certain fishes and toothed whales and sea lions Some fish can have serrated teeth Serrations on triangular teeth of piranhas allow them to slice the flesh of their prey Tiger sharks have serrated teeth which allows them to bite through the carapace of sea turtles

Answer 6

Structures formed by teeth being found on the tongue, roof of the mouth, gill rakers, and pharyngeal arches of fishes Lower pharyngeal jaws of a grass carp crushes plants against a horny pad on the roof of the pharynx Lower pharyngeal jaws of the bream is full of molars opposed by a mobile upper pharyngeal jaw with which it crushes prey such as crabs and shellfish → The separation of functions of jaw structures permitted huge adaptive radiations among the cichlids, sunfishes, and carps

Answer 7

Allowed fishes to breathe and chew at the same time Mouth could become highly specialised to use the pharyngeal jaw to crush, puncture, and drag prey into the esophagus

Answer 8

Larval stage that is much smaller than the adult Functions such as crushing plants and snails are not possible because of the size of the pharyngeal jaws The larvae of most ray-finned fishes feed on plankton, then change to a juvenile diet when they get bigger and then adopt their adult diet when they mature

Answer 9

There is no larval stage, and their diet shifts only due to change in size and habitat

Answer 10

Diets change as the fish grows

Answer 11

Tend to have streamlined bodies Have eyes set forward on the head

Answer 12

Eyes directed anteriorly are likely used for stereoscopic vision - Characteristic of carnivores Eyes set laterally – wide field of vision to detect predators - Characteristic of herbivores - Also true for terrestrial predators and herbivores

Answer 13

Used to recover insects from their habitats - Used by echidnas – lack teeth and only need a small mouth as jaws cannot open wide

Answer 14

Used by amphibians such as frogs to capture insects and even other amphibians - Amphibians can also have small teeth – usually just patches of denticles that are used to grasp prey

Answer 15

Important structure in terrestrial vertebrates

Answer 16

In the mouth – uses incisors or molars to cut and crush prey - Pharyngeal teeth Breaking up prey accelerates chemical digestion – digestive juices can more rapidly access the higher surface area for a given volume of food → Animal mode of feeding can be assigned by comparing the relative ease of digestion of different food groups Assess features of the post buccopharyngeal alimentary tract – esophagus, stomach, and intestine

Answer 17

Cellulose is a sugar that is difficult for animals to digest without microbes via microbial fermentation - Herbivores tend to have long guts

Answer 18

The first barrier that the food must pass from the buccopharynx is the esophagus - In animals that swallow large chunks of food or whole prey, the esophagus tends to be pleated to allow the food chunk to pass - If you investigate the back of the mouth (aka buccopharyngeal cavity) of a mystery vertebrate – can see the pleating or lack thereof - Some predators that swallow large prey whole might have very small jaw teeth but have a deeply pleated esophagus -- Frogs, herons, and tuna - Humans have a weakly pleated esophagus and need to chew their food thoroughly before the food bolus is moved to the esophagus - The esophageal wall tends to be rich in mucus cells, the mucus from which lubricates the food on its way to the main digestive tract - Some animals store food prior to it being moved to the stomach

Answer 19

Some birds have a widening of the esophagus called a crop and some rodents use check pouches to store food - In birds the esophagus empties into the first section of the two-part stomach, the proventriculus - After treatment with acid secretions in the proventriculus, the food is passed to the gizzard, the muscular part of the stomach that further macerates the food - Sometimes this is done with the aid of ingested sand or pebbles, known as gastroliths

Answer 20

tend to periodically eat large meals

Answer 21

Have large, distensible, pot-like stomachs in which the meal is slowly macreated An empty stomach is strongly pleated Eat a large amount of food intermittently Terrestrial examples – crocodiles and lions Marine example – sharks and groupers

Answer 22

eat prey much smaller than themselves and tend to eat frequent, small meals

Answer 23

Generally have small stomachs and relatively short intestines The prey are smaller particles and readily accessible for digestion due to high surface area of the stomachs