Biological Molecules

Question 1

How and where is glucose stored in plants

Answer 1

Starch, stored in chloroplasts and sinks such as tubers

Question 2

How and where is glucose stored in animals

Answer 2

Glycogen, stored in liver

Question 3

State one similarity and two differences between starch and glycogen

Answer 3

• both glucose
• starch–>plants, glycogen–>animals
• starch is coiled

Question 4

Which elements make up carbohydrates

Answer 4

C, H, O

(carbon, hydrogen, oxygen)

Question 5

Which elements make up proteins

Answer 5

C, H, O, N

(carbon, hydrogen, oxygen, nitrogen)

some, but not all, may contain a small quantity of sulfur (S)

Question 6

Which elements make up lipids

Answer 6

C, H, O

(carbon, hydrogen, oxygen)

much less oxygen than carbohydrates

Question 7

Shape of glucose

Answer 7

hexagon

Question 8

Test for reducing sugars

Answer 8

Benedicts solution

Question 9

Default color of benedict’s solution

Answer 9

blue

Question 10

Positive test result for benedict’s solution

Answer 10

orange-red

(spectrum, turns green and yellow first before turning orange-red)

Question 11

Test for starch

Answer 11

Iodine

Question 12

Positive test result for starch with iodine

Answer 12

Blue/black

Question 13

How is the liver involved with regulating glucose levels in blood

Answer 13

If there is too much glucose in bloodstream, the liver links it together and stores it as glycogen

Question 14

What is a fat molecule made of?

Answer 14

One glycerol and three fatty acids

Question 15

How is a fatty acid molecule represented

Answer 15

/\/\/\/\/\/\/\/\/\/\/\

Question 16

What is the difference between fats and oils

Answer 16

fats are solid at room temp, oils are liquid at room temp

Question 16

Two types of lipids

Answer 16

fats and oils

Question 17

Solubility of lipids

Answer 17

Insoluble in water, soluble in ethanol

Question 18

Test for lipids

Answer 18

Ethanol emulsion test

Question 19

Emulsion

Answer 19

a liquid containing two sibstances that do not fully mix where one forms tiny droplets dispersed throughout the other

Question 20

How does the ethanol emulsion test work

Answer 20

The food is shaken with ethanol, allowing potential lipids to dissolve in it. The ethanol is then placed in water. Lipids are immiscible and insoluble with water, so the lipids dissolved in ethanol will form an emulsion with water, giving it a milky appearance

Question 21

Uses for fats in animals

Answer 21

• making cell membranes
• energy storage
• insulation (retain heat)
• forms around organs and protects them

Question 22

Tissue where fats are is stored in humans

Answer 22

Adipose tissue, beneath the skin

Question 23

What are proteins made of?

Answer 23

Amino acids

Question 24

Uses for proteins in animals

Answer 24

• enzymes, which catalyze metabolic reactions
• antibodies, which protect body from pathogens
• haemoglobin, pigment in red blood cells that binds to oxygen
• carrier proteins, for active transport
• keratin —> hair and fingernails
• DNA!!!!!

Question 25

Test for proteins

Answer 25

Biuret reagent

Question 26

Which biological molecule stores the most energy per gram

Answer 26

lipids

Question 27

Uses for glucose in plants

Answer 27

• energy for active transport
• growth (building proteins)
• starch (storage)
• sucrose (transportation)
• cellulose (cell walls)
• nectar (attracts pollinators)
• create amino acids
• create chlorophyll

Question 28

Positive test result biuret reagent

Answer 28

Purple!

Question 29

Default color biuret reagent

Answer 29

Blue

Question 30

Test for Vitamin C

Answer 30

DCPIP

Question 31

Positive result DCPIP

Answer 31

colorless

Question 32

Default color DCPIP

Answer 32

Purple

Question 33

Breakdown of starch steps

Answer 33

Starch (long coil) —> Maltose (two glucoses) —> Glucose (single unit)