Topic 4

Question 1

Species Richness

Answer 1

Number of Species in a habitat/community

Question 2

Speciation

Answer 2

Two or more species emerge from a species

Question 3

How does Evolution occur?

Answer 3

When two species are reproductively isolated , natural selection separates species

Question 4

Biodiversity

Answer 4

The complexity of a biological community

Question 5

Habitat

Answer 5

Area where an organisms lives

Question 6

Factors which effect Biodiversity?

Answer 6

• Human Population Growth
• Agriculture
• Climate Change

Question 7

Evolution

Answer 7

Causes Reproductively isolated populations to evolve in different directions

Question 8

Monoculture

Answer 8

Practise where farmers grow only one crop species in field

Question 9

Adaptation definition

Answer 9

traits that have been selected for because they help increase an organisms chance of survival

Question 10

Example of Behavioural Adaptations

Answer 10

• Evolved to increase survival

- Can be learnt or inherited

Question 11

Example of Anatomical Adaptations

Answer 11

-Physical Structures to increase survival

Question 12

Example of Physiological Adaptations

Answer 12

-Processes within the body that have evolved

Question 13

Natural Selection

Answer 13

-Process that leads to evolution in a population

Question 14

Four Key principles of Natural Selection

Answer 14

• Random Mutation
• Variation in Mutations
• Inheritance
• Change in allele frequency

Question 15

What is Random Mutation

Answer 15

• Changes in gene sequence of DNA
• Can arise spontaneously
• Result in alleles of a gene

Question 16

What is Variations in Mutations

Answer 16

• Most mutations are harmful
• Alter function of a gene
• If you have a beneficial allele you can survive and reproduce

Question 17

How does Inheritance effect Natural Selection

Answer 17

• Individual Reproduces
• inherit half its genes
• Advantageous allele also passed on

Question 18

Biological Definition of a Species

Answer 18

-A population of organisms that can interbreed to produce fertile offspring

Question 19

Taxa

Answer 19

-A group of closely related organisms

Question 20

Whats is Taxa dependent on?

Answer 20

-Phylogeny of organisms (evolutionary)

Question 21

What is the Hierarchy divided to for classification

Answer 21

• Smaller taxa

- Organisms can only belong to one taxa

Question 22

7 Stages in Linnaean Hierarchy

Answer 22

• Kingdom
• Phylum
• Class
• Order
• Family
• Genius
• Species

Question 23

3 Groups Woese concluded

Answer 23

Archaea - primitive bacteria
Bacteria - true bacteria
Eukaryota - organisms possessing sub-cellular structures

Question 24

Chloroplasts function

Answer 24

-Carry out photosynthesis

Question 25

Cellulose

Answer 25

-main component of plant and algal cell walls

Question 26

Chitin

Answer 26

-main component of fungal walls

Question 27

What is Xylem responsible for

Answer 27

-transporting water and mineral ions

Question 28

Structure of a Xylem

Answer 28

- Long tubes of cells - No end of tubes (continuous flow of water) - Lignin - provides structural support

Question 29

What are cells of xylem vessels called

Answer 29

-vessel elements (dead)

Question 30

How does water flow up the Xylem

Answer 30

-Cohesion-Tension Theory

Question 31

4 steps of the Cohesion-Tension Theory

Answer 31

1) Transpiration 2) Tension 3) Cohesion 4) Diffusion in roots

Question 32

Xylem flow of water - Transpiration

Answer 32

- Water leaves leaves via transpiration | - Some leaves as used in respiration

Question 33

Xylem flow of water - Tension

Answer 33

- Formation of hydrogen bonds between water molecules and side of vessel elements - Due to loss of water via leaves - Pulls water upto leaves

Question 34

Xylem flow of water - Cohesion

Answer 34

-Individual water molecules form hydrogen bonds with eachother

Question 35

Xylem flow of water - Diffusion in Roots

Answer 35

- When water pulled up stem - Water potential decreases - Diffuses via osmosis - Creates conc. gradient

Question 36

Steps in Water transport in Xylem?

Answer 36

1) Water evaporated from leaves - transpiration 2) Loss of water creates tension in xylem 3) Water pulled upwards via xylem 4) Water molecules form Hydrogen bonds via cohesion 5) Water pulled upwards via cohesion 6) Water diffuses through roots to replace water lost in bottom