UNIT 3- Sustainability and Interdependence Flashcards
Food security
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.
Plant Productivity
The rate at which crop plants generate new biomass per unit of time.
Net assimilation
The increase in biomass due to photosynthesis, minus the loss due to respiration.
Biological yield
The total plant biomass.
Economic Yield
The biomass of desired product.
Harvest Index
Economic Yield/Biological Yield
Absorption Spectra
Shows the % of light absorbed by photosynthetic pigments at different wavelengths.
Action Spectra
Shows the relative rate of photosynthesis at different wavelengths.
Photolysis
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.
RuBisCO
The enzyme that catalyses the reaction where RuBP and carbon dioxide combine.
Inbreeding
This involves the fertilisation of gametes from closely related individuals within a species.
Inbreeding Depression
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.
Outbreeding
This involves the fertilisation of gametes from two unrelated members of the same species.
Cross Breeding
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.
Back Cross
When a hybrid is crossed with one of its parents or an organism with the same genetic characteristics as one of the parents.
Test Cross
Test done to determine if an individual is homozygous or heterozygous for a trait.
Field Trial
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.
Annual Weed
Weed that has a short life cycle, produces many seeds that remain viable for a long time and reproduces sexually.
Perennial Weed
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.
Nematode
Pest that bores into host plant and parasitises the plant tissue.
Molluscs
Pest with specialised mouthparts that can easily breakdown tough plant material.
Insects
Pest that that has piercing or biting mouthparts that can penetrate or chew plant tissues.
Selective Herbicide
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.
Systemic Herbicide
Absorbed and transported through the plant’s vascular system totally destroying the plant and preventing regrowth.
Biological Control
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.
Integrated Pest Management
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.
Ethogram
An objective diagram or list which describes animal behaviour.
Preference Test
Involves giving an animal a choice between two or more conditions and making measurements about which condition the animal chooses.
Motivation test
Involves measuring the extent to which an animal seeks out a basic need such as food or water.
Mutualistic Relationship
Relationship where both species of organism involved benefit from the interdependent relationship. They often cannot survive without each other.
Parasitic Relationship
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.
Vector
An intermediate organism that transfers a parasite from one host to another eg. The female anopheles mosquito is the vector for plasmodium.
Altruistic Behaviour
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.
Kin Selection
A type of naturalselectionin which an individual attempts to ensure the survival of its own genes by protecting closely related individuals first
Mass extinction
When many species all die out around the same time.
Megafauna
Term applied to land animals bigger than humans.
Genetic Diversity
The number and frequency of alleles in a population.
Species Diversity
The number and relative abundance of different species in an ecosystem.
Ecosystem Diversity
The number of distinct ecosystems in a defined area.
Bottleneck Effect
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.
Invasive Species
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.
