4b

Question 1

Biotic conditions

Answer 1

Plant and animal communities

Question 2

Changes in abiotic conditions

Answer 2

Water availability

Question 3

Primary succession

Answer 3

Happens on land that has been newly formed or exposed. (Where a volcano has erupted to form new rock surfaces)

Question 4

Secondary succession

Answer 4

Happens on land that’s been cleared of all plants but where soil remains (after a forest fire)

Question 5

Climax community

Answer 5

Final stage of succession - the ecosystem is supporting the largest and most complex community of plants and animals it can. It’s at a steady state and won’t change much more!

Question 6

Succession

Answer 6

Is the process if ecosystem change over time

Question 7

Primary succession - abiotic conditions are hostile means??

Answer 7

There’s no soul to retain water - pioneer plants are specialised to cope with long roots ect

Question 8

Primary succession - abiotic conditions are less hostile means??

Answer 8

The basic soil is deeper and helps to retain water and structure for new organisms. Soil = deeper and richer in minerals !

Question 9

What is a plagioclimax?

Answer 9

When human activity prevents succession, stopping a climax community from developing. When succession is stopped artificially!

Question 10

Examples of human activity that cause plagioclimax ?

Answer 10

Animals grazing on land

Managed fires are lit.

Question 11

Species ?

Answer 11

A species is a group of similar organisms that can reproduce to give fertile offspring

Question 12

Population ?

Answer 12

A population is a group if organisms of the same species living in a particular area.

Question 13

The gene pool?

Answer 13

The gene pool is the complete range of alleles present in a population

Question 14

Hardy-Weinberg principle

Answer 14

Predicts that the frequency of alleles in a population won’t change from one generation to the next.

Question 15

Conditions needed for the Hardy Weinberg principle to apply ??

Answer 15

Large population where there's....
NO immigration
NO emigration
NO mutations
NO natural selection 

There also needs to be random mating
(All possible genotypes can breed with all others)

Question 16

How does ATP store energy?

Answer 16

Bonds between phosphate groups are unstable and have a low activation energy - meaning they are easily broken and they release a lot of energy!

Question 17

What do organisms need energy for?

Answer 17

Metabolism
Movement
Active transport
Maintenance, repair and division
Production if substances
Maintenance of body temperature

Question 18

The synthesis of ATP from ADP and Pi occurs in three ways??

Answer 18

Photophosphorylation

Oxidative phosphorylation

Substrate-level phosphorylation

Question 19

What is photophosphorlyation??

Answer 19

It takes place in chlorophyll containing plant cells during photosynthesis

Question 20

What is oxidative phosphorylation?

Answer 20

Occurs in mitochondria of plant and animal cells during the electron transport chain

Question 21

What is substrate-level phosphorylation??

Answer 21

It occurs in plant and animal cells when phosphate groups are transferred from phosphate groups to ADP to make ATP.
E.G. In the formation of pyruvate at the end of glycolysis

Question 22

ATP is an ___________ energy source for the cell?

Answer 22

Immediate energy source.

Cells store only a few seconds supply

Question 23

Why is ATP a better immediate energy source than glucose?? (2 points)

Answer 23

Energy from ATP is released in smaller more manageable quantities rather than glucose releasing the opposite.

The hydrolysis of ATP is a single reaction. The breakdown of glucose is a series of reactions and energy release takes longer

Question 24

How does ATP provide energy for metabolic processes??

Answer 24

ATP provides energy to build up macromolecules from their basic units…

Polysaccharide synthesis from monosaccharides
Polypeptide synthesis from amino acids
DNA/RNA synthesis from nucleotides

Question 25

What is the hydrolysis of ATP?

Answer 25

Bonds between the phosphates in ATP are unstable and have a low Ea and are easily broken. Aka hydrolysis (addition f water)