QCAA Biology — definitions + identify/recall questions

clade (QCAA)

a group of organism that consists of a common ancestor and all its lineal descendants

ecological niche (QCAA)

the role and space that an organism fills in an ecosystem, including all its interactions with the biotic and abiotic factors of its environment

keystone species (QCAA)

a plant or animal that plays a unique and crucial role in the way an ecosystem functions

carrying capacity (QCAA)

the size of the population that can be supported indefinitely on the available resources and services of that ecosystem

genome (QCAA)

all the genetic material in the chromosomes of an organism, including its genes and DNA sequences

gene (QCAA)

region/s of DNA that are made up of nucleotides; the molecular unit of heredity

polygenic inheritance (QCAA)

when one characteristic is controlled by two or more genes

evolution (QCAA)

change in the genetic composition of a population during successive generations, which may result in the development of new species

microevolution (QCAA)

small-scale variation of allele frequencies within a species or population, in which the descendant is of the same taxonomic group as the ancestor

macroevolution (QCAA)

the variation of allele frequencies at or above the level of species over geological time, resulting in the divergence of taxonomic groups, in which the descendant is in a different taxonomic group to the ancestor

identify one example of an interspecific hybrid that does not produce fertile offspring

the mule

identify the features of pioneer species

ability to fixate nitrogen, tolerance to extreme conditions, rapid germination of seeds, ability to photosynthesise

describe the process of making recombinant DNA

isolation of DNA

cutting of DNA (restriction enzymes)

insertion of DNA fragment (plasmid vector)

joining of DNA (DNA ligase)

amplification of recombinant DNA (bacterial transformation)

recall the common assumptions of cla districts

common ancestry, bifurcation and physical change

recall the structure of DNA

- nucleotide composition

- complementary base pairing

- weak, base specific H bonds between DNA strands

recall an example of a transcription factor gene that regulates morphology

HOX transcription factor family

recall an example of a transcription factor gene that regulates cell differentiation

sex determining region of Y

recall how speciation and macro evolutionary changes occur

from an accumulation of microevolutionary changes over time, along with reproductive isolation and exposure to differing selective pressures

describe the process of stratified sampling on a site e.g. rainforest site

purpose: what you want to measure e.g to assess the vertical vegetation structure by considering vegetation cover

identify: an ecological surveying technique e.g. a point transect

describe: a sampling process e.g. use a sampling fraction to determine sample size

minimising: bias e.g. calibrating equipment used to measure

presentation: of data e.g. a bar graph with error bars

analysis: of data e.g. standard error/confidence intervals