Human Digestive System

Question 1

Heterotrophic

Answer 1

Organisms that are not capable of making their own food

Question 2

Autotrophic

Answer 2

Organisms capable of making their own food

Question 3

Herbivore

Answer 3

Eat plants only

Question 4

Carnivore

Answer 4

Eats animals only

Question 5

Omnivore

Answer 5

Eats both animals and plants

Question 6

Photosynthesis

Answer 6

Use of light energy to make food

Question 7

Chemosynthesis

Answer 7

Use of chemical energy to make food

Question 8

Saprophytic (decomposers)

Answer 8

Organisms that obtain their food from dead organisms

Question 9

Parasitic

Answer 9

Two organisms of different species live together where one benefits and causes harm to the other

Question 10

Symbiotic

Answer 10

Organisms that live in close contact with a second species and at least one organism benefits

Question 11

Egestion

Answer 11

Removal of unabsorbed waste

Question 12

Excretion

Answer 12

Removal of waste products of metabolism

Question 13

Peristalsis

Answer 13

Rhythmic muscular contraction and relaxation in the wall of the alimentary canal causing the movement of food

Question 14

Deamination

Answer 14

Breaking down excess amino acids to form urea (in the liver)

Question 15

Balanced diet

Answer 15

Contains the correct amounts of each food type for good health

Question 16

Stages of nutrition

Answer 16

Ingestion
Digestion
Absorption
Egestion

Question 17

Ingestion

Answer 17

Taking in food

Question 18

Digestion

Answer 18

Physical and chemical break down of food into smaller molecules

Question 19

Absorption

Answer 19

Food diffuses into the bloodstream

Question 20

Types of digestion

Answer 20

Mechanical (physical break down)

Chemical (addition of digestive enzymes)

Question 21

Why is digestion necessary

Answer 21

To make food soluble
Easier to absorb
Transport

Question 22

Mouth

Answer 22

Chemical digestion - salivary amylase (starch->maltose)

Mechanical - teeth, tongue

Question 23

Types of teeth

Answer 23

Incisors - cutting
Canines - gripping and tearing
Molars - crushing and grinding
Pre molars - crushing and grinding

Question 24

Teeth formula

Answer 24

i 2. C 1 Pm2. M3

2. 1. 2. 3

Question 25

Oesophagus

Answer 25

Mechanical - peristalsis to move food from mouth to stomach

Question 26

Stomach

Answer 26

Location - abdominal cavity Mechanical - churned into chyme Chemical - digestive enzymes break down food Hydrochloric acid and lysozyme produced to kill bacteria

Question 27

Gastric juice

Answer 27

``` Produced in stomach Contains: mucous - lines and protects stomach wall HCI - kills bacteria, converts pepsinogen to pepsin Pepsin - breaks down proteins ```

Question 28

Pancreas

Answer 28

Located in the abdominal cavity below the stomach Produces amylase and lipase Produces insulin

Question 29

Liver

Answer 29

``` Located above the stomach in the upper abdomen Makes bile Helps to detoxify the body Deamination Converts glucose to glycogen Stores vitamins and minerals ```

Question 30

Bile

Answer 30

Composition - water, bile salts, bile pigments Emulsify (break down) fats Neutralise chyme from stomach and provides optimum pH for enzymes

Question 31

Gall bladder

Answer 31

Located in the liver Stores bile Releases bile into the duodenum through the bile duct

Question 32

Small intestine

Answer 32

Parts - duodenum, ileum, jejenum | Absorption and digestion

Question 33

Duodenum

Answer 33

Chemical digestion - lipase (fats) and amylase (carbs)

Question 34

Ileum

Answer 34

Absorbs nutrients into bloodstream (by diffusion)

Question 35

Ileum adaptations for absorption

Answer 35

Long tube - allows time for reabsorption Villi - infoldings which increase the surface area available for reabsorption Walls are one cell thick - allows substances to diffuse easily into bloodstream

Question 36

How fat is absorbed into the small intestine

Answer 36

Villi 1. Fatty acids and glycerol are absorbed into the lacteal 2. Re form into fats 3. Diffuse into bloodstream through blood vessels Peristalsis occurs at muscular wall

Question 37

Hepatic portal vein

Answer 37

Only vein not connected directly to the heart Connects the ileum with the liver Transports amino acids, glucose to the liver Amino acids broken down into urea Urea leaves liver through the hepatic vein

Question 38

Large intestine

Answer 38

Parts - caecum, appendix, rectum (stores faeces) Reabsorbs water Symbiosis

Question 39

Symbiosis

Answer 39

Bacteria feed on waste to produce vit B and K | Break down cellulose, return the nutrients to small intestine

Question 40

Benefit of fibre

Answer 40

Prevents constipation by stimulating peristalsis in the colon

Question 41

Constipation

Answer 41

Too much water reabsorbed when undigested food moves too slowly

Question 42

Faeces

Answer 42

Liquid waste in large intestine

Question 43

Amylase

Answer 43

Produced in : salivary glands/ pancreas Secreted to and active in : mouth / duodenum pH : 7-9 alkaline Role : digest starch -> maltose

Question 44

Pepsin

Answer 44

Produced in : stomach Secreted to and active in : stomach pH : 2 acidic Role : digest proteins -> peptides

Question 45

Lipase

Answer 45

Produced in : pancreas Secreted to and active in : duodenum pH : 7-9 alkaline Role : fats -> fatty acids and glycerol

Question 46

Amino acids

Answer 46

Products formed by complete digestion of protein

Question 47

Peptides

Answer 47

Short chains of amino acids