Topic 4- Biodiversity and Natural Resources

Question 1

4.1. Know that over time the variety of life has become extensive but is now being
threatened by human activity.

Question 2

4.2. (i) Understand the terms biodiversity and endemism.

Question 3

4.2. (ii) Know how biodiversity can be measured within a habitat using species
richness and within a species using genetic diversity by calculating the
heterozygosity index (H):
H= (number of heterozygotes/ number of individuals in the population)

Question 4

4.2. (iii) Understand how biodiversity can be compared in different habitats using a
formula to calculate an index of diversity .

Question 5

4.3.Understand the concept of niche and be able to discuss examples of adaptation
of organisms to their environment (behavioural, physiological and anatomical).

Question 6

4.4. Understand how natural selection can lead to adaptation and evolution

Question 7

4.5. (i) Understand how the Hardy-Weinberg equation can be used to see whether a
change in allele frequency is occurring in a population over time

Question 8

4.5. (ii) Understand that reproductive isolation can lead to accumulation of different
genetic information in populations potentially leading to the formation of new
species

Question 9

4.6. (i) Understand that classification is a means of organising the variety of life
based on relationships between organisms using differences and similarities in
phenotypes and in genotypes, and is built around the species concept.

Question 10

4.6. (ii) Understand the process and importance of critical evaluation of new data by the scientific community, which leads to new taxonomic groupings, including
the three domains of life based on molecular phylogeny, which are Bacteria,
Archaea, Eukaryota.

Question 11

4.7. Know the ultrastructure of plant cells (cell walls, chloroplasts, amyloplasts,
vacuole, tonoplast, plasmodesmata, pits and middle lamella) and be able to
compare it with animal cells.

Question 12

4.8. Be able to recognise the organelles in (4.7) from electron microscope (EM)
images

Question 13

4.9. Understand the structure and function of the polysaccharides starch and
cellulose, including the role of hydrogen bonds between β-glucose molecules in
the formation of cellulose microfibrils.

Question 14

4.10. Understand how the arrangement of cellulose microfibrils and secondary
thickening in plant cell walls contributes to the physical properties of xylem
vessels and sclerenchyma fibres in plant fibres that can be exploited by
humans.

Question 15

Discuss CORE PRACTICAL 6:
Identify sclerenchyma fibres, phloem sieve tubes and xylem vessels and their
location within stems through a light microscope.

Question 16

4.11. Know the similarities and differences between the structures, position in the
stem and function of sclerenchyma fibres (support), xylem vessels (support
and transport of water and mineral ions) and phloem (translocation of organic
solutes).

Question 17

4.12. Understand the importance of water and inorganic ions (nitrate, calcium ions
and magnesium ions) to plants.

Question 18

Discuss CORE PRACTICAL 7:
Investigate plant mineral deficiencies.

Question 19

Discuss CORE PRACTICAL 8:
Determine the tensile strength of plant fibres.

Question 20

4.13. Understand the development of drug testing from historic to contemporary
protocols, including William Withering’s digitalis soup, double blind trials,
placebo, three-phased testing.

Question 21

4.14. Understand the conditions required for bacterial growth.

Question 22

Discuss CORE PRACTICAL 9:
Investigate the antimicrobial properties of plants, including aseptic techniques
for the safe handling of bacteria.

Question 23

4.15. Understand how the uses of plant fibres and starch may contribute to
sustainability, including plant-based products to replace oil-based plastics

Question 24

4.16. Be able to evaluate the methods used by zoos and seed banks in the
conservation of endangered species and their genetic diversity, including
scientific research, captive breeding programmes, reintroduction programmes
and education.