chapter 5- nutrition in humans

Question 1

what are the enzymes that digest starch and maltose?

Answer 1

amylase and maltase

Question 2

what are the enzymes that digest proteins and polypeptides?

Answer 2

protease and peptidase

Question 3

what are the enzymes that digest fats?

Answer 3

lipase

Question 4

what are the end products of starch?

Answer 4

glucose

Question 5

what are the end products of proteins?

Answer 5

amino acids

Question 6

what are the end products of fats?

Answer 6

glycerol and 3 fatty acids

Question 7

what is chemical digestion?

Answer 7

it is the breakdown of large insoluble food molecules into smaller and soluble food molecule for absorption by body cells with PPM

Question 8

what is physical digestion? give a few examples.

Answer 8

it is the mechanical breakdown of food where it helps to increase the surface are to volume area so that digestion is faster. a few examples: stomach churning/chewing/ emulsion of fats

Question 9

where is fats digested?

Answer 9

in the duodenum of the small intestine

Question 10

is bile produced by the liver or the gallbladder?

Answer 10

the liver. the bile is stored in the gallbladder

Question 11

why is emulsification of fats speed up digestion of fats?

Answer 11

the bile produced by the liver emulsifies the fats into the tiny fat droplets. this increases the surface area to volume ratio for faster digestion by the lipase.

Question 12

what is the function of the mouth?

Answer 12

the mouth contains the enzyme, amylase, and breaks down the starch into maltose. it contains teeth to chew large food pieces into smaller food pieces to increase the surface area for faster digestion.

Question 13

what is the function of the oesophagus?

Answer 13

it brings the food down from the mouth to the stomach

Question 14

what is the function of the small intestine

Answer 14

it breaks down starch fully into glucose, proteins to amino acids and fats into fatty acids and glycerol where it would all be absorbed (with water) and transported to the rest of the body.

Question 15

what is the function of the stomach?

Answer 15

it digests proteins into polypeptides

Question 16

what is the function of the large intestine?

Answer 16

absorbs water from undigested food
rectum: stores undigested food
anus: egests undigested food

Question 17

what is the function of the liver?

Answer 17

produces bile and it stores excess glucose (converted to glycogen) for storage and excess amino acids to be broken down to form the urea

Question 18

what is the function of the gallbladder?

Answer 18

stores the bile

Question 19

what is the function of the pancreas?

Answer 19

produces pancreatic juices that contains enzymes (amylase, lipase and protease). it secretes hormones (insulin and glucagon).

Question 20

what is the function of salivary glands?

Answer 20

secretes saliva (water, mucus and amylase)

Question 21

what is the specialised organ in the small intestine?

Answer 21

villi

Question 22

what are the characteristics of a villus?

Answer 22

it is one cell think so that diffusion is faster. (small intestine is 6 to 7 metres long so rate of diffusion increases because there is more time)

Question 23

what is the function of a villus?

Answer 23

it increases the surface area to volume ratio for faster absorption/ diffusion of digested nutrients

Question 24

what is the flow of the transportation of glucose and amino acids?

Answer 24

from the small intestine, to the hepatic portal vein and to the liver.

Question 25

what are the excess glucose converted to?

Answer 25

glycogen

Question 26

what are the excess amino acids converted to?

Answer 26

deaminated in the liver and removed from the body to form the urea

Question 27

what is the excess fats converted to?

Answer 27

it is stored in the fat tissues (adipose)

Question 28

what is digested fats used for?

Answer 28

to synthesise cell membranes