biological molecules + mass transport

Question 1

what atoms make up a lipid?

Answer 1

• carbon
• oxygen
• hydrogen

Question 2

what is a triglyceride?

Answer 2

A lipid made up of 3 fatty acid tails + glycerol

Question 3

what bond joins glycerol to its fatty acid tails?

Answer 3

ester bond

Question 4

glycerol structure

Answer 4

CH2 - OH
|
CH - OH
|
CH2 - OH

Question 5

fatty acid structure

Answer 5

COOH-R

Question 6

what does a C=C bond do to a fatty acid

Answer 6

causes the tail to kink

Question 7

are fatty acid tails soluble in water and why/ why not?

Answer 7

insoluble in water as they are hydrophobic and non-polar

Question 8

what are all macromolecules made up of?

Answer 8

hydrogen, oxygen and carbon

Question 9

name 3 monosaccharides

Answer 9

glucose, fructose and galactose

Question 10

whats general formula for a monosaccharide?

Answer 10

(CH2O)n

Question 11

are monosaccharides soluble?

Answer 11

yes

Question 12

whats the most commonly found type of monosacchide?

Answer 12

hexose sugars

Question 13

what type of sugar is fructose?

Answer 13

pentose

Question 14

what type of sugar is galactose?

Answer 14

hexose

Question 15

what type of sugar is glucose?

Answer 15

hexose

Question 16

formula of respiration

Answer 16

glucose + oxygen → carbon dioxide + water + ATP

Question 17

How is glucose well adapted for it’s role? [3]

Answer 17

• small, so easily transported into and out of cells
• soluble, so easily transported in blood
• not very reactive, so breakdown can only occur if catalysed therefore enzymes can control rate of respiration

Question 18

are disaccharides soluble?

Answer 18

yes

Question 19

name 3 disaccharides

Answer 19

maltose, sucrose and lactose

Question 20

what monosaccharides make up maltose?

Answer 20

a-glucose + a-glucose

Question 21

what monosaccharides make up sucrose?

Answer 21

a-glucose + fructose

Question 22

what monosaccharides make up lactose?

Answer 22

a-glucose + galactose

Question 23

where is maltose found?

Answer 23

in germinating seeds

Question 24

where is sucrose found?

Answer 24

plants

Question 25

where is lactose found?

Answer 25

mammalian milk

Question 26

what bond forms between 2 monosaccharides to form a disaccharide?

Answer 26

Glycosidic bond

Question 27

are polysaccharides soluble?

Answer 27

NO

Question 28

are polysaccharides sugars?

Answer 28

NO

Question 29

how are polysaccharides broken down?

Answer 29

via a series of hydrolysis reactions

Question 30

how are polysaccharides formed?

Answer 30

via a series of condensation reactions

Question 31

How are polysaccharides well adapted for storage of glucose?

Answer 31

- large so cannot diffuse out of cells via carrier proteins - insoluble so doesn't affect osmotic balance of cell - compact so lots of energy in a small space - broken down quickly so readily accessible energy source

Question 32

whats the main storage of energy in plants?

Answer 32

starch

Question 33

where and how is starch stored in plants?

Answer 33

in amyloplasts as insoluble grains

Question 34

what is starch made up of?

Answer 34

different polysaccharides of alpha-glucose: amylose and amylopectin

Question 35

what are amylose and amylopectin made up of?

Answer 35

alpha-glucose

Question 36

describe the structure of amylose

Answer 36

- long chain of alpha-glucose - 1,4 glycosidic bonds only - compact helix spiral - only 2 accessible ends

Question 37

is amylose broken down quickly or slowly?

Answer 37

slowly - only 2 accessible ends

Question 38

describe the structure of amylopectin

Answer 38

- branches of alpha-glucose - helix spirals - 1,4 AND 1,6 glycosidic bonds - lots of accessible ends

Question 39

is amylopectin broken down quickly or slowly

Answer 39

quickly - lots of accessible ends

Question 40

is amylose or amylopectin a faster release of glucose?

Answer 40

amylopectin as it has lots more accessible ends

Question 41

whats the main storage of energy in animals/ fungi?

Answer 41

Glycogen

Question 42

where is glycogen found in animals and why is it mainly found in these places?

Answer 42

in the liver and muscle cells (as they both have high metabolic rates)

Question 43

describe the structure of glycogen

Answer 43

- alpha-glucose - 1,4 AND 1,6 glycosidic bonds - lots of accessible ends

Question 44

why is it important that glycogen have lots of accessible ends?

Answer 44

- main storage of energy in animals - animals very high metabolic requirements - lots of accessible ends = quick release of energy to meet these metabolic requirements

Question 45

What are the 2 isomers of glucose and how do you tell them apart?

Answer 45

- alpha glucose has both -OH groups facing downwards (cis) - beta glucose has -OH groups facing opposite ways (trans) (up on the side of the O)

Question 46

Explain how 2 properties of water make it an ideal transport medium [4]

Answer 46

- polar, so can dissolve ions/ polar - cohesive, so has the ability to flow

Question 47

why do single-celled organisms not need a circulation system but larger organism do? [2]

Answer 47

single-celled organisms have a larger surface area:volume ratio and therefore a shorter diffusion pathway

Question 48

explain why a human needs a heart [3]

Answer 48

to supply oxygen/ glucose to cells/ remove CO2 from the body via mass transport as the surface area:volume ratio is too small for diffusion to occur at a sufficient rate