Component 3.3 - Adaptations To Different Diets

Question 1

Why do carnivores have a shorter gut than herbivores?

Answer 1

Because protein and lipids are easily digested but a herbivore has a longer gut because plant material e.g cellulose is not readily digested.

Question 2

What is the function of the incisors and canine teeth in herbivores?

Answer 2

The incisors and the canines look the same. The tongue wraps around the grass and it is cut against the horny pad.

Question 3

What happens in the diastema of herbivores?

Answer 3

Allows manipulation of food by the tongue, moving the freshly cut grass to the large grinding surface of the molars.

Question 4

Describe the structure and function of molars in herbivores

Answer 4

They interlock like a W and a M. Loose articulation of lower jaw moves means it can move in a circular motion for grinding.

Question 5

What are the jaw muscles like in a herbivore and why?

Answer 5

It does not need strong muscles attached to its jaws, because it’s food is not likely to escape.

Question 6

What is a herbivores skull like and why?

Answer 6

It is relatively smooth, reflecting the absence of sites for strong muscles to attach.

Question 7

What are incisors for in carnivores?

Answer 7

They strip flesh from bone

Question 8

What are canine teeth like in carnivores and what do they do?

Answer 8

They are large and pointed for piercing and seizing prey

Question 9

What are the function of premolars and molars in carnivores?

Answer 9

They have cusps which are sharp points that cut and crush

Question 10

What movement do carnassials make and what is their function?

Answer 10

They slide past each other and have sharp cutting edges to slice flesh

Question 11

What is the skull like in a carnivore?

Answer 11

There are protrusions on the skull, where strong jaw muscles insert into the bone for maintaining hold on prey

Question 12

Why do some animals need mutualistic microbes?

Answer 12

Animals do not make cellulose and cannot digest the beta-glycosidic bonds in cellulose. They therefore need the microbes living in their gut to secrete the enzymes.

Question 13

Where abouts in the gut do mutualistic microbes live?

Answer 13

In a chamber called the Rumen.

Question 14

What happens to the grass in the mouth of a cow? (1)

Answer 14

It is cut by the teeth and mixed with saliva to form cud, which is swallowed down the oesophagus.

Question 15

What happens to the cud in the rumen? (2)

Answer 15

Food is mixed with microbes that secrete enzymes, digesting cellulose to glucose.

Question 16

What happens to the glucose produced from cellulose in the rumen? (2)

Answer 16

It is fermented to organic acids which are absorbed into the blood and are an energy source for the cow. Carbon dioxide and methane are released.

Question 17

What happens to the grass grass in the reticulum? (3)

Answer 17

It is reformed into cud then it is regurgitated into the mouth for further chewing (may be regurgitated and swallowed several times)

Question 18

Where does the cud go after it had been in the reticulum? (3)

Answer 18

It passed into the omasum where water and organic acids made from fermented glucose are absorbed into the blood.

Question 19

Where does the cud pass into after it has been in the omasum? (4)

Answer 19

Into the abomasum where protein is digested by pepsin.