Biological Molecules

Question 1

Elements in Carbohydrates + example

Answer 1

Carbon, Hydrogen, Oxygen + simple sugars (glucose)

Question 2

elements in lipids + example

Answer 2

carbon, hydrogen, oxygen + fatty acids, glycerol

Question 3

elements in protein + example

Answer 3

carbon, hydrogen, oxygen, nitrogen + amino acids (20)

Question 4

structure of carbohydrates

Answer 4

long chain of simple sugars (monosaccharides)
2 simple sugras = disaccharides
lots of simple sugars = polysaccharides e.g. glycogen

Question 5

structure of lipids

Answer 5

most common type = triglyceride - made of two difference sub units called glycerol and fatty acids

Question 6

structure of proteins

Answer 6

long chain of amino acids - can join together to make hundreds / thousands of protein types

Question 7

biological catalysts (enzymes)

Answer 7

they change the rate of reaction but are not changed in the reaction

Question 8

enzymes are proteins

Answer 8

made up of long chains of amino acids folded into specific shapes

Question 9

synthetic reactions

Answer 9

large molecules built up from small molecules e.g. forming muscles

Question 10

breakdown reactions

Answer 10

splitting large molecules into smaller ones e.g. amylase breaks starch into maltose

Question 11

lock and key hypothesis

Answer 11

enzymes are specifically shaped to only fit one type of substrate (on active site)

Question 12

reactions up to 40 degrees

Answer 12

as temp increases so does the rate of reaction because particles have more kinetic energy and so more collisions per second
37˚ = human body temp

Question 13

reactions above 40 degrees

Answer 13

enzymes start to change shape so active site no longer fits substrate = denatured - can’t break down substrate

Question 14

food test for starch

Answer 14

iodine - added directly to substance - red turns blue/black

Question 15

food tests for proteins

Answer 15

biuret solution - added directly to substance - blue turns purple

Question 16

test for reducing sugar

Answer 16

add to solution and hear for 2 minutes

blue turns brick red (orange/green if less)

Question 17

food test for lipids (emulsion test)

Answer 17

add ethanol and shake thoroughly and add water - colourless turns cloudy

Question 18

protease 1 (produced in, act in, substrate, product)

Answer 18

produced in stomach wall cells, small intestine, pancreas
act in stomach, small intestine
optimum ph 2/8 (HCL acidifies food, bile neutralises acid)
substrate protein, product amino acids

Question 19

salivary amylase (produced in, act in, substrate, product)

Answer 19

produced in salivary glands, act in mouth, ph 8, substrate starch, product maltose, sugars

Question 20

lipase (produced in, act in, substate, product)

Answer 20

produced in pancreas, small intestine wall cells, act in small intestine, ph8, substrate lipids, product fatty acids, glycerol