UNIT 3- Sustainability and Interdependence

Question 1

Food security

Answer 1

The ability of humans to access a sufficient quality and quantity of food. This can refer to a household, a town, a country or a region of the world.

Question 2

Plant Productivity

Answer 2

The rate at which crop plants generate new biomass per unit of time.

Question 3

Net assimilation

Answer 3

The increase in biomass due to photosynthesis, minus the loss due to respiration.

Question 4

Biological yield

Answer 4

The total plant biomass.

Question 5

Economic Yield

Answer 5

The biomass of desired product.

Question 6

Harvest Index

Answer 6

Economic Yield/Biological Yield

Question 7

Absorption Spectra

Answer 7

Shows the % of light absorbed by photosynthetic pigments at different wavelengths.

Question 8

Action Spectra

Answer 8

Shows the relative rate of photosynthesis at different wavelengths.

Question 9

Photolysis

Answer 9

The splitting of water into hydrogen and oxygen using energy from the light. Hydrogen then combines the NADP and oxygen is given off as a by-product.

Question 10

RuBisCO

Answer 10

The enzyme that catalyses the reaction where RuBP and carbon dioxide combine.

Question 11

Inbreeding

Answer 11

This involves the fertilisation of gametes from closely related individuals within a species.

Question 12

Inbreeding Depression

Answer 12

There is decreasing heterozygosity with each generation and a build up of deleterious recessive alleles and there are number of homozygous individuals carrying these deleterious recessive alleles. This is caused by persisting with inbreeding in natural “outbreeders”- natural inbreeders have had harmful recessive alleles removed by natural selection.

Question 13

Outbreeding

Answer 13

This involves the fertilisation of gametes from two unrelated members of the same species.

Question 14

Cross Breeding

Answer 14

This involves fertilisation of gametes from two different breeds within a species. This can result in a genetically and physically stronger F1 offspring which has desirable characteristics from each parents. This is called hybrid vigour.

Question 15

Back Cross

Answer 15

When a hybrid is crossed with one of its parents or an organism with the same genetic characteristics as one of the parents.

Question 16

Test Cross

Answer 16

Test done to determine if an individual is homozygous or heterozygous for a trait.

Question 17

Field Trial

Answer 17

A controlled experiment done to compare the performance of different cultivars or how plots of one cultivar perform with a range of treatments such as different fertiliser applications.

Question 18

Annual Weed

Answer 18

Weed that has a short life cycle, produces many seeds that remain viable for a long time and reproduces sexually.

Question 19

Perennial Weed

Answer 19

Weed that persists from year to year, has storage organs, has a competitive advantage as it is established before the crop grows and reproduces asexually.

Question 20

Nematode

Answer 20

Pest that bores into host plant and parasitises the plant tissue.

Question 21

Molluscs

Answer 21

Pest with specialised mouthparts that can easily breakdown tough plant material.

Question 22

Insects

Answer 22

Pest that that has piercing or biting mouthparts that can penetrate or chew plant tissues.

Question 23

Selective Herbicide

Answer 23

Absorbed through the leaves and overstimulates the metabolism of the plant killing the leafy parts. Broadleaved weeds absorb a lot more than the crops with narrow leaves and are quickly affected.

Question 24

Systemic Herbicide

Answer 24

Absorbed and transported through the plant’s vascular system totally destroying the plant and preventing regrowth.

Question 25

Biological Control

Answer 25

When a pest’s natural enemy is introduced to the crop to help keep its numbers in check. This can be a problem if it escapes into the wild as it can disrupt the ecosystem and even become an invasive species.

Question 26

Integrated Pest Management

Answer 26

An ecosystem-based strategy that focuses on long-term prevention ofpestsor their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.

Question 27

Ethogram

Answer 27

An objective diagram or list which describes animal behaviour.

Question 28

Preference Test

Answer 28

Involves giving an animal a choice between two or more conditions and making measurements about which condition the animal chooses.

Question 29

Motivation test

Answer 29

Involves measuring the extent to which an animal seeks out a basic need such as food or water.

Question 30

Mutualistic Relationship

Answer 30

Relationship where both species of organism involved benefit from the interdependent relationship. They often cannot survive without each other.

Question 31

Parasitic Relationship

Answer 31

Relationship where the parasite benefits from the host by taking energy and/or nutrients from the host and the host is harmed. The parasite often has a limited metabolism and cannot survive out of contact with their host- so the best parasites do not actually kill their hosts.

Question 32

Vector

Answer 32

An intermediate organism that transfers a parasite from one host to another eg. The female anopheles mosquito is the vector for plasmodium.

Question 33

Altruistic Behaviour

Answer 33

Unselfish behaviour which harms the donor but benefits the recipient. Often takes the form of reciprocal altruism where the understanding is that the favour will be returned.

Question 34

Kin Selection

Answer 34

A type of naturalselectionin which an individual attempts to ensure the survival of its own genes by protecting closely related individuals first

Question 35

Mass extinction

Answer 35

When many species all die out around the same time.

Question 36

Megafauna

Answer 36

Term applied to land animals bigger than humans.

Question 37

Genetic Diversity

Answer 37

The number and frequency of alleles in a population.

Question 38

Species Diversity

Answer 38

The number and relative abundance of different species in an ecosystem.

Question 39

Ecosystem Diversity

Answer 39

The number of distinct ecosystems in a defined area.

Question 40

Bottleneck Effect

Answer 40

This will be caused by a bottleneck event that drastically reduces a population’s number reducing genetic variability. Many of the survivors are genetically similar so inbreeding will occur further reducing variability. So then, if there is an environmental change the species may not be able to adapt.

Question 41

Invasive Species

Answer 41

Species that spreads rapidly and outcompetes indigenous species causing their decline. Invasive species often spread so rapidly because in their new environment they do not have any of their natural predators, parasites or diseases.