all units

Primary Succession

Ecological succession starting within a uninhabited environment such as barren rock.

Secondary succession

Ecological succession begins with a pre-existing disturbed community, the presences of soil and other organisms makes the recovery faster.

Genetic Drift

change in the frequency of an existing allele within the population due to random chance.

Gene flow

transfer alleles from one population to another

Transect surveying

Ecological surveying technique with ability to analyse the distribution of a species across the environmental gradient

Quadrat Surveying

Ecological surveying technique that has the ability to analyse the frequency and density of a species.

Stratified sampling

Stratified sampling technique involved in dividing ecosystem into equal strata which effective as it ensures subgroups are represented within the population.

Random sampling

All organisms have an equal chance of being represented in the sample.

Systematic sampling

Organisms are organised and every nth organism is chosen to be within the sample. - Limited because you need pre-existing advice

Spermatozoa

A motile sperm cell, or moving form of the haploid cell that is the male gamete.

spermatocyte

A male gametocyte, from which a spermatozoon develops.

spermatid

A haploid cell produced by meiosis of a spermatocyte that develops into a spermatozoon.

Spermatogonium

Any of the undifferentiated cells in the male gonads that become spermatocytes.

Does Meiosis occur before spermatogenesis or oogenesis?

Yes.

describe the process of making recombinant DNA?

involves isolating DNA, cutting it with restriction enzymes, joining the desired fragments using DNA ligase, and inserting the new DNA into a host organism where it can be replicated and potentially expressed

Natural selection

Natural selection is a mechanism for evolution, which explains how individuals with traits best suited to their environment are most likely to survive, reproduce and pass on their alleles to the next generation.

Preferential Mating

The Hardy-Weinberg model assumes that all individuals in a population have the same chance of breeding with each other. That is, it only works for populations which have random mating.