Topic 4A - Biodiversity

Question 1

EQ. Describe what is meant by biodiversity (2 marks)

Answer 1

• the variety of species within a habitat

- the variety of alleles in a population

Question 2

Define endemic

Answer 2

a species that’s only found in one geographical location

Question 3

EQ. Suggest how natural selection could have given rise to certain adaptations (5 marks)

Answer 3

• selection pressures creates a struggle for survival
• such as predation
• mutations introduce new alleles into the population
• individuals with advantageous alleles are more likely to survive
• and therefore pass on advantageous alleles to their offspring
• so there will be an increased frequency of advantageous alleles in the population

Question 4

EQ. Explain how two species of African elephant could evolve from a common ancestor. (3 marks)

Answer 4

• when 2 populations are geographically isolated from each other
• they experience different selection pressures so they develop different adaptations
• and there is a reduced gene flow between the 2 populations
• this leads to allopatric speciation

Question 5

Define species

Answer 5

organisms that can interbreed to produce fertile offspring.

Question 6

What is the hierarchy of taxonomy?

Answer 6

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
(Dumb King Phillip Came Over From Great Spain)

Question 7

What are the five kingdoms?

Answer 7

Animalia
Plantae
Fungi
Protoctista
Prokaroytae.

Question 8

To which group do fungi belong?

Answer 8

eukaryota

Question 9

Define species richness

Answer 9

the number of different species in an area

Question 10

Define population size

Answer 10

the number of individuals per species

Question 11

EQ. Eukarya is one of the three domains. Name the other two domains. (2 marks)

Answer 11

• archaea

- bacteria

Question 12

EQ. Scientists classify organisms into taxonomic groups, such as the three domains. Explain how organisms can be classified into taxonomic groups. (2 marks)

Answer 12

• organisms with similar characteristics are placed in the same group
• characteristics like behavioral similarities and molecular phylogeny

Question 13

EQ. Woese suggested that organisms could be placed in taxonomic groups based on molecular phylogeny. Explain what is meant by this statement. (4 marks)

Answer 13

• organisms with similar charactersitics are placed in the same group
• each taxonomic group have specific differences
• molecular phylogeny looks at the similarities in the DNA sequence
• and shows the evolutionary relationship through genetics

Question 14

Define niche

Answer 14

the position occupied by an organism in its ecosystem

Question 15

EQ. Explain what is meant by the term niche, using the plant Epilobium latifolium as an example. (3 marks)

Answer 15

• niche is the role of epilobium latifolium within its ecosystem
• epilobium latifolium is a producer
• and provides energy for primary consumers
• and adds nutrients and humus to the soil

Question 16

EQ. Describe how to carry out a study of the distribution of Epilobium latifolium from the front edge of this glacier. (4 marks)

Answer 16

• take a transect along a line from the front edge of this glacier
• place quatrats
• at regular intervals of 10m
• estimate percentage cover by counting the number of squares covered by epilobium latifolium

Question 17

EQ. Suggest one abiotic factor that might affect the abundance of Epilobium latifolium and describe how this factor could be measured. (4 marks)

Answer 17

• water content may be a factor
• take a soil sample around the roots
• weigh soil samples before and after drying it (until you find a constant mass) and find difference
• take multiple readings and find average

Question 18

Describe the difference between biodiversity within a species and biodiversity within a habitat.

Answer 18

biodiversity within a species is the variety of alleles within a species and biodiversity within a habitat is the variety of species within a habitat

Question 19

EQ. A pond had a low index of diversity. Explain how the composition of this community could have resulted in this low index of diversity (2 marks)

Answer 19

• low species richness which lowers N

- some species may be abundant while other species are few which lowers n

Question 20

Woese suggested that there are three domains based on evidence from…

Answer 20

molecular phylogeny

Question 21

The 2 domains that contain prokaryotic cells are…

Answer 21

archaea and bacteria

Question 22

EQ. Herbicides are sprayed on a lawn to kill unwanted plants. Explain how the index of diversity would change. (2 marks)

Answer 22

• index of diversity would decrease

- because there will be fewer species present

Question 23

EQ. Explain what is meant by the term molecular phylogeny. (3 marks)

Answer 23

• looking at molecular similarities and differences
• in the DNA
• used to see the evolutionary relationships between organisms

Question 24

EQ. Describe the 3 types of adaptations and an example for each. (3 marks)

Answer 24

• behavioural is the way an organism acts e.g scorpions dance to increase the chance to successful mating
• physiological is the chemical processes e.g brown bears hibernate by slowing their metabolism
• anatomical is the structural features e.g otters have a streamline shape so they can swim faster in water

Question 25

Define phylogeny

Answer 25

the evolutionary relationships

Question 26

What 2 things does the index of diversity take into account?

Answer 26

species richness and abundance

Question 27

EQ. Explain how the primary structure of trypsin molecules can be used to produce a phylogenetic tree. (3 marks)

Answer 27

• we should determine the primary structure
• we find similarities or differences in the primary structure
• the more similar the primary structure the more closely related they are

Question 28

EQ. Describe what needs to be measured in order to compare the biodiversity of 2 rainforests. (2 marks)

Answer 28

• measure species richness

- determine population size