Human Nutrition

Question 1

Nutrition

Answer 1

The process by which an organism obtains and uses its food

Question 2

Functions of nutrition

Answer 2

• Energy Source
• Growth
• Repair

Question 3

What are the two types of nutrition?

Answer 3

Autotrophs and heterotrophs

Question 4

What are the stages of human nutrition?

Answer 4

Ingestion
Digestion
Absorption
Assimilation
Egestion

Question 5

Ingestion

Answer 5

The intake of food - through mouth

Question 6

Digestion

Answer 6

Breaking up of food into smaller soluble pieces - in mouth, stomach, small intestine

Question 7

Absorption

Answer 7

Transfer of food from stomach/ intestines into bloodstream and lymphatic system for distribution

Question 8

Assimilation

Answer 8

Use of digested food in the body

Question 9

Egestion

Answer 9

Getting rid of undigested food - anus

Question 10

Role of mouth in nutrition

Answer 10

Physical digestion by teeth

Question 11

What are the four types of teeth?

Answer 11

Incisor
Canine
Premolar
Molar

Question 12

Human dental formula

Answer 12

2 (I 2/2 C 1/1 PM 2/2 M 3/3 )

Question 13

How many teeth is the permanent total, for an adult?

Answer 13

32

Question 14

What makes chemical digestion occur?

Answer 14

By salivary amylase, produced by salivary glands

Question 15

What is the equation for the breakdown of starch?

Answer 15

Starch —Amylase—> maltose

Question 16

Peristalsis

Answer 16

The rhythmic contraction and relaxation of muscles

Question 17

What is food called after it is physically digested in the mouth?

Answer 17

Bolus

Question 18

What is food called after it is physically churned by the stomach?

Answer 18

Chyme

Question 19

What is the acid in the stomach called?

Answer 19

Hydrochloric acid

Question 20

How does hydrochloric acid aid in breaking down proteins ?

Answer 20

Pepsinogen (Gastric juice ) converts to pepsin using hydrochloric acid.

Proteins use this pepsin to break down into peptides.

Question 21

Mucus

Answer 21

Thick, sticky, alkaline substance lining wall of stomach, protecting it from self digestion

Question 22

What are the two parts of the small intestine?

Answer 22

Duodenum and ileum

Question 23

What neutralises acidic chyme?

Answer 23

Sodium Hydrogen Carbonate (NaHCO3)

Question 24

Where does Sodium Hydrogen Carbonate come from?

Answer 24

Pancreas

Question 25

What are villi?

Answer 25

Infoldings on the lining of the small intestine

Question 26

What does a villi contain?

Answer 26

Microvilli Capillaries Lacteal

Question 27

What does bile do?

Answer 27

Emulsify fats

Question 28

Where does bile come from?

Answer 28

Gall bladder

Question 29

What are the pancreatic enzymes?

Answer 29

Amylase, lipase, protease

Question 30

Amylase - substrate, enzyme, product

Answer 30

Starch - Amylase - Maltose

Question 31

Lipase - substrate, enzyme, product

Answer 31

Fats - Lipase - Fatty Acids and Glycerol

Question 32

Protease - substrate, enzyme, product

Answer 32

Peptides - Protease - Amino Acids

Question 33

What occurs in the ileum?

Answer 33

Absorption of digested food into circulatory system

Question 34

Adaptations of villi

Answer 34

Large surface area Thin, one cell thick, walls Rich blood capillary network

Question 35

Labelled diagram of villi

Answer 35

Look in Notes

Question 36

What do capillaries absorb?

Answer 36

Glucose Amino acids Water soluble vitamins Minerals

Question 37

What do lacteals absorb?

Answer 37

Fatty acids and glycerol Cholesterol Fat soluble vitamins

Question 38

Adaptation of small intestine

Answer 38

Long Villi walls are thin Each villus has a lymph supply

Question 39

Function of large intestine

Answer 39

Water reabsorption and elimination of faeces

Question 40

What role does fibre play in the diet

Answer 40

Prevents constipation by stimulating peristalsis Reduced risk of colon cancer

Question 41

Benefits of symbiotic intestinal bacteria

Answer 41

Provide us with vitamins B and K Help digest cellulose May protect against cancer

Question 42

Functions of liver

Answer 42

Produces bile Detoxifies poisonous substances eg alcohol Produces heat to warm the body Removes excess amino acids by breaking them down to urea

Question 43

What forms bile?

Answer 43

Remains of dead red blood cells

Question 44

How do pancreatic enzymes enter the small intestine?

Answer 44

Pancreatic duct