Topic 18: Biodiversity, Classification, and Conservation

Question 1

Definitions I:
(a) Species
(b) Biodiversity
(c) Ecosystem

Answer 1

(a) Species: Group interbreeding, producing fertile offspring. (1 mark)
(b) Biodiversity: Variety of life in an area. (1 mark)
(c) Ecosystem: Community plus environment. (1 mark)

Question 2

Discuss the biological species concept in frogs. [2 Marks]

Answer 2

Frogs interbreed, fertile offspring (1 mark); Defines species biologically (1 mark). (2 marks)

Question 3

Describe the three domains of life in a soil sample. [2 Marks]

Answer 3

Archaea, Bacteria: Prokaryotes (1 mark); Eukarya: Eukaryotes, nucleus (1 mark). (2 marks)

Question 4

In bacteria, state differences between Archaea and Bacteria. [2 Marks]

Answer 4

Archaea: Unique lipids, RNA (1 mark); Bacteria: Peptidoglycan walls (1 mark). (2 marks)

Question 5

Classify a lion into the Eukarya taxonomic hierarchy. [3 Marks]

Answer 5

Kingdom: Animalia, Phylum: Chordata (1 mark); Class: Mammalia, Order: Carnivora (1 mark); Family: Felidae, Genus: Panthera, Species: leo (1 mark). (3 marks)

Question 6

Outline features of the Plantae kingdom in a forest. [2 Marks]

Answer 6

Multicellular, photosynthetic (1 mark); Cellulose walls, chloroplasts (1 mark). (2 marks)

Question 7

Classify an RNA virus from a flu sample. [2 Marks]

Answer 7

RNA virus, single-stranded (1 mark); Classified by nucleic acid (1 mark). (2 marks)

Question 8

Define niche and ecosystem in a pond habitat. [2 Marks]

Answer 8

Niche: Species’ role in habitat (1 mark); Ecosystem: Organisms plus abiotic factors (1 mark). (2 marks)

Question 8

In a meadow, explain how biodiversity is assessed at three levels. [3 Marks]

Answer 8

Ecosystems: Habitat variety (1 mark); Species: Count, abundance (1 mark); Genes: Variation within species (1 mark). (3 marks)

Question 9

Explain random sampling’s importance in a woodland survey. [2 Marks]

Answer 9

Random sampling avoids bias (1 mark); Ensures accurate biodiversity data (1 mark). (2 marks)

Question 10

In a grassland, use quadrats and transects to assess plant abundance. [3 Marks]

Answer 10

Quadrats count plants randomly (1 mark); Transects show distribution (1 mark); Abundance calculated (1 mark). (3 marks)

Question 11

In a jungle, explain how climate change causes species extinction. [4 Marks]

Answer 11

Climate shifts habitats (1 mark); Species can’t adapt fast (1 mark); Competition increases (1 mark); Extinction follows (1 mark). (4 marks)

Question 12

Calculate Lincoln index for rabbits (50 marked, 40 recaptured, 10 marked). [3 Marks]

Answer 12

N = (50 × 40) / 10 = 200 (1 mark); Mark-release-recapture (1 mark); Estimates population (1 mark). (3 marks)

Question 13

Use Simpson’s index (D) for a reef (5 species, n/N = 0.2 each). [3 Marks]

Answer 13

D = 1 - Σ(0.2²), D = 0.8 (1 mark); High D, diverse reef (1 mark); Calc shows biodiversity (1 mark). (3 marks)

Question 14

Outline reasons to maintain biodiversity in a wetland. [2 Marks]

Answer 14

Supports ecosystems, food chains (1 mark); Genetic resources, stability (1 mark). (2 marks)

Question 15

In a zoo, describe IVF and surrogacy for conserving pandas. [3 Marks]

Answer 15

IVF fertilises eggs (1 mark); Embryo transfer to surrogate (1 mark); Boosts panda numbers (1 mark). (3 marks)

Question 16

Explain CITES and IUCN roles in conserving endangered tigers. [4 Marks]

Answer 16

IUCN assesses threats (1 mark); CITES bans trade (1 mark); Protect tigers (1 mark); Global coordination (1 mark). (4 marks)