6 - Animal Nutrition

Question 1

What is a balanced diet?

Answer 1

A balanced diet consists of all the food groups in correct proportions

Question 2

What are the necessary food groups?

Answer 2

Carbohydrates, proteins, lipids, vitamins, minerals, dietary fibre and water.

Question 3

What is the function and source of Carbohydrates?

Answer 3

Source of energy, from bread, cereals, pasta, rice, potatoes

Question 4

What is the function and source of protein?

Answer 4

Growth and repair, from meat, fish, eggs, pulses, nuts

Question 5

What is the function and source of lipids?

Answer 5

Insulation and energy storage from butter, oil, nuts

Question 6

What is the function and source of dietary fibre?

Answer 6

Provides bulk for the intestine to push the food through it, from vegetables, whole grains.

Question 7

What is the function and source of vitamins?

Answer 7

Needed in small quantities to maintain health, from fruits and vegetables.

Question 8

What is the function and source of minerals?

Answer 8

Needed in small quantities to maintain health, from fruits, vegetables, meats and dairy products

Question 9

What is the function and source of water?

Answer 9

Needed for chemical reactions to take place in cells, from water, juice, milk, fruits and vegetables.

Question 10

What is Vitamin C needed for?

Answer 10

Forms collagen protein which makes up skin, hair, gums and bones. Deficiency causes scurvy. From citrus fruits, strawberries and green vegetables.

Question 11

What is Vitamin D needed for?

Answer 11

Helps the body absorb calcium and required for strong bones and teeth. Found in oily fish, eggs, liver, dairy products, sunlight. Deficiency causes rickets.

Question 12

What is calcium needed for?

Answer 12

Strong teeth and bones and involved in clotting of blood. Deficiency can lead to osteoporosis. From milk, cheese, eggs.

Question 13

What is Iron needed for?

Answer 13

Needed to make haemoglobin, pigment in red blood cells that transports oxygen. From red meat, liver, leafy green vegetables. Deficiency causes anaemia.

Question 14

What is malnutrition and what are it’s types?

Answer 14

It is caused by not eating a balanced diet. Types include starvation, coronary heart disease, constipation and obesity.

Question 15

What is the cause and effect of starvation?

Answer 15

Caused by taking in less energy than is used. Effect - body starts breaking down energy stores, leading to weight loss and eventually heart and immune system damage, increasing risk of diseases.

Question 16

What is the cause and effect of coronary heart disease?

Answer 16

Caused by a diet too high in saturated fat and cholesterol. Effect - fat deposits reduce blood flow to heart, causing it to not work due to lack of oxygen, can lead to heart attacks.

Question 17

What is the cause and effect of constipation?

Answer 17

Caused by lack of fibre in diet. Effect - food lacks bulk for muscles to push it through alimentary canal and risk of diseases such as bowel cancer are increased.

Question 18

What is the cause and effect of obesity?

Answer 18

Caused by taking in more energy than is used. Effect - extra energy stored as fat, weight increases and causes diseases such as heart disease and diabetes.

Question 19

What are the two types of protein energy malnutrition?

Answer 19

Kwashiorkor and Marasmus.

Question 20

What is ingestion?

Answer 20

The taking in of substances, such as food or drink, into the body through the mouth.

Question 21

What is digestion?

Answer 21

The breakdown of large, insoluble food molecules into small, water-soluble molecules using mechanical and chemical processes.

Question 22

What is mechanical digestion?

Answer 22

The breakdown of food into smaller pieces without chemical change to the food molecules.

Question 23

What is chemical digestion?

Answer 23

The breakdown of large, insoluble molecules into small, soluble molecules

Question 24

What is absorption?

Answer 24

The movement of digested food molecules through the wall of the intestine into the blood.

Question 25

What is assimilation?

Answer 25

The movement of digested food molecules into the cells of the body where they are used, becoming part of the cells.

Question 26

What is egestion?

Answer 26

The passing out of food that has not been digested, as faeces, through the anus.

Question 27

What are the parts of the alimentary canal?

Answer 27

Mouth, salivary glands, oesophagus, stomach, small intestine, pancreas, liver, gall bladder, large intestine and anus.

Question 28

What is the mouth’s function?

Answer 28

Mechanical digestion occurs. Teeth chew food to break it into smaller pieces and increase its surface area, amylase enzymes in saliva start digesting starch into maltose, food is shaped into a bolus by tongue and lubricated by saliva to be swallowed.

Question 29

What is the Oesophagus’s function?

Answer 29

It is a tube that connects the mouth to the stomach where the bolus goes after being swallowed. Wave-like contractions push the bolus down without relying on gravity.

Question 30

What is the stomach’s function?

Answer 30

Food is mechanically digested by churning actions while protease enzymes start to chemically digest proteins. Hydrochloric acid is present to kill bacteria in food and provide optimum pH for protease enzymes to work.

Question 31

What is the small intestine’s function?

Answer 31

pH is slightly alkaline (8-9). First section is called duodenum and is where the food coming out from the stomach finishes being digested by enzymes produced here and secreted from pancreas. Second section is called Ileum and is where absorption of digested food molecules takes place. Ileum is long and lined with Villi to increase surface area for absorption.

Question 32

What is the large intestine’s function?

Answer 32

Water is absorbed from remaining material in the colon to produce faeces. Faeces stored in rectum and removed through anus.

Question 33

What is the pancreas’ function?

Answer 33

Produces amylase, protease and lipase. Secretes enzymes in alkaline fluid into duodenum for digestion to raise pH of fluid coming out of stomach.

Question 34

What is the liver’s function?

Answer 34

Produces bile to emulsify fats. Amino acids not used to make proteins are broken down which produces urea.

Question 35

What is the gall bladder’s function?

Answer 35

It stores bile to release into duodenum as required.

Question 36

What are the types of teeth?

Answer 36

Incisors (chisel shaped for biting and cutting), canines (pointed for tearing, holding and biting), premolars and molars (larger, flat surfaces with ridges at the edges for chewing and grinding up food).

Question 37

How is dental decay caused?

Answer 37

By bacteria. Plaque coats teeth and areas where they attach to gums, hardens over time and forms tartar. It can allow bacteria to work their way into roots, causing gum disease and loss of teeth. If sugar is left in mouth after eating, bacteria in plaque will feed on it, use it in respiration and turn it into acids that gradually dissolve the enamel of the teeth, working its way to the dentine.

Question 38

What are the functions of enzymes?

Answer 38

Amylase - breaks down starch to simpler sugars
Protease - breaks down protein to amino acids
Lipase - breaks down fats to fatty acids and glycerol. All secreted by the pancreas.

Question 39

What is the function of hydrochloric acid in gastric juice?

Answer 39

Killing bacteria in food and giving an acid pH for enzymes (denatures enzymes in harmful microorganisms in food, gives optimum pH for protease activity.)

Question 40

What is the role of bile?

Answer 40

It’s alkaline to neutralise the hydrochloric acid that comes from the stomach, enzymes in small intestine have a higher optimum pH than in stomach. Breaks down large drops of fat into small ones (emulsification). Larger surface area allows lipase to chemically break down lipid faster.

Question 41

Why are villi important?

Answer 41

They are tiny, finger-like projections that increase the internal surface area of the small intestine to allow absorption to occur faster.

Question 41

Why are villi important?

Answer 41

They are tiny, finger-like projections that increase the internal surface area of the small intestine to allow absorption to occur faster.

Question 42

What are the roles of lacteal and blood capillaries in a villus?

Answer 42

It’s well supplied with a network of blood capillaries that transport glucose and amino acids away from the small intestine in blood. Lacteal runs through the center of the villus to transport fatty acids and glycerol away from the small intestine.