Unit 2 - Organisms And Evolution (word definitions) Flashcards
absolute fitness
the ratio of frequencies of a particular genotype from one generation to the next
antropomorphism
crediting animal behaviour with human emotions or qualities (personification)
antigen
a protein that may induce an immune response if it is foreign
antigenic variation
where parasites show great variety amongst different strains
apoptosis
cell death
autosome
any chromosome that is not a sex chromosome
bacteriophage
a virus that targets a bacterial host
chiasmata
the place where two homologous chromosomes come into contact with one another
civil engineering
a profession that is involved in the design and manufacture of infrastructure to improve standards of living
clonal selection
lymphocytes become amplified, with some clones used in immediate defence and other clones acting as memory cells
co-evolution
where a change in the traits of one species acts as a selection pressure on another species with which it frequently interacts
commensalism
an interrelationship between organisms of two different species in which one species in which one species benefits and the other neither benefits nor suffers
competitive exclusion principle
when two species are in intense competition with one another and the weaker of the two species becomes locally extinct
crossing over
the process where homologous chromosomes swap genetic material
cysticerosis
a parasitic tissue infection
definitive (primary) host
host where parasite reaches sexual maturity
epidemiology
the study of the outbreak and spread of infectious diseases
ethogram
chart on which observed animal behaviour is recorded
ethology
study of animal behaviour
evolution
the change, over successive generations, in the proportion of individuals in a population differing in one or more inherited traits
extended phenotype
a theory whereby the parasite modifies the host’s behaviour to increase its own transmission
fundamental niche
the niche that an organism occupies when there are no other species present competing for space or resources
gravid proglottid
the segment of a tapeworm containing both male and female reproductive organs
hermaphrodite
an organism with both male and female reproductive organs
heterogametic
dissimilar sex chromosomes e.g. mammalian males where the Y chromosome is much smaller than the X chromosome
homologous chromosomes
chromosomes of the same shape and size, same centromere position and which carry the same genes at the same gene loci
genetic drift
the random change in how frequent a particular allele occurs within a small population
immune surveilllance
white blood cells patrol the body, recognising and destroying foreign pathogens
independent assortment
takes place during meiosis I when homologous chromosomes pair up and line up along the equator - the final position of one pair is completely random relative to every other pair
inflammatory response
injured or wounded areas become warm and red due to increase blood flow, bringing white cells for defence
intermediate (secondary) host
the host that the parasite might require in order to complete its life cycle or as a means of transmission thus making it a vector
interphase
takes place at the start of meiosis when DNA replication occurs
K-selected
larger organisms that usually produce lower numbers of offspring, providing more extensive parental care and have longer life spans
lekking
makes display for females in a communal display area, then females chooses a mate
transect line
line along which quadrats are placed or samples are taken`
linked genes
genes that are on the same chromosome
lysis
the bursting of a host cell, releasing many virus particles