Digestive System

Question 1

Digestion

Answer 1

The physical and chemical breaking down of food into its constituents molecules, which can be absorbed into the bloodstream

Question 2

Ingestion

Answer 2

The process of taking in food (mouth)

Question 3

Absorption

Answer 3

The passage of single biomolecules from the gut into the bloodstream

Question 4

Assimilation

Answer 4

The movement of digested food molecules into the cells of the body where they are used

Question 5

Ejestion

Answer 5

The getting rid of undigested material from the body.

Question 6

Stages of Digestion

Answer 6

Ingestion
Digestion
Absorption
Assimilation
Ejestion

Question 7

Physical/Mechanical Digestion

Answer 7

Teeth
Muscle, e.g. muscle of the stomach
chewing
Churning 
Peristalsis

Question 8

Buccal Cavity

Answer 8

Teeth or chewing (Mechanical Digestion)

Question 9

Salivary Glands

Answer 9

Produces saliva to digest bolus of food (Chemical Digestion)

Question 10

Oesophagus

Answer 10

Food to Stomach by peristalsis

a wave of muscular contractions

Question 11

Stomach

Answer 11

Muscular bag lined with gastric glands
Secretes gastric juices
Churns and mixes food with gastric juices

Question 12

Adaptions of stomach

Answer 12

Mucous - goblet cells - prevent self-digestion
Pepsinogen - zymogen cells - Inactive enzymes
Hydrochloric acid - oxyntic cells - Kills bacteria

Question 13

Small Intestine

Answer 13

Duodenum, jejunum and ileum
Lined with villi
Each villus has 600 microvilli
Produces Vitamin B and K
Receives pancreatic juices from pancreas and bile from gall bladder
Absorption (glucose, amino acids, fatty acids)

Question 14

Large Intestine

Answer 14

Holds food
Caecum and appendix - vestigial organs
Colon reabsorbs water
Faeces stored in rectum

Question 15

Symbiotic Bacteria

Answer 15

Colon bacteria feed on wate in large intestine and produces Vitamin B and K

Question 16

Pancreas

Answer 16

Exocrine gland produces pancreatic juices (duct)
Endocrine gland produces insulin (ductless)
Pancreatic amylase and pancreatic lipase
Sodium hydrogen carbonate neutralises chyme

Question 17

Liver

Answer 17

• Makes bile (Emulsifies fats and excrete pigments)
• Detoxifies body
• Deamination (Removing amino part to excess nitrogen)
• Makes fibrinogen

Question 18

Villus

Answer 18

One cell thick
Good network of blood capillaries
LSA due to large number of microvilli

Question 19

Peristalsis

Answer 19

Rhythmic muscular contraction and relaxation in the wall of the alimentary canal causing the food to move along the canal

Question 20

Canines

Answer 20

Tearing

Question 21

Incisors

Answer 21

Cutting

Question 22

Molars and Pre-molars

Answer 22

Crushing and Grinding

Question 23

Humans Dental Formula

Answer 23

I 2/2, C 1/1, PM 2/2, M 3/3

Question 24

Baby Teeth

Answer 24

20 teeth

Question 25

Adult Teeth

Answer 25

32 teeth

Question 26

Amylase

Answer 26

Made in salivary glands Active in mouth pH 7 Starch to maltose

Question 27

Protease

Answer 27

Made in salivary glands (gastric juices) Active in stomach pH 2 Proteins to polypepetides

Question 28

Pepsin

Answer 28

Made in gastric glands Active in stomach pH 1/2 Protein to peptides

Question 29

Lipase

Answer 29

Made in pancreas Active in duodenum pH 8 Lipids to glycerol and fatty acids

Question 30

Balanced Diet

Answer 30

A diet that consists of all 7 nutrients in the right amount to meet the needs of the body

Question 31

Advantages of Dietary Fibre

Answer 31

Stimulates peristalsis in the colon | Helps prevent constipation

Question 32

Cause of constipation

Answer 32

When undigested materials pass through too slowly | Too much water is being reabsorbed

Question 33

Mouth

Answer 33

Physical digestion

Question 34

Chemical Digestion

Answer 34

Starch using amylase to maltose

Question 35

Adaptations of Small Intestine

Answer 35

``` Made of muscle Duodenum produces enzymes Long Has villi Thin walls ```