Unit 2: Organisms And Evolution Flashcards
Absolute fitness
The ratio of frequencies of a particular genotype from one generation to the next
Active
Requires energy
Active site
The region of an enzyme molecule where the substrate binds
Ameba
A single-called parasite
Angiosperms
Flowering plants
Anthropomorphism
Crediting animal behaviour with human emotions or qualities
Antigen
A protein that may induce an immune response if it is foreign
Antigenic variation
Where parasites show great variation amongst different strains
Apoptosis
Programmed cell death
Archaea
One of the three domains of life, consisting of single felled micro organisms
Arthropoda
Jointed-legged invertebrates which are identified by their segmented body, typically with paired appendages
Examples: wasps, butterflies, spiders and crabs
ATP synthase
A membrane bound enzyme which generates ATP
Autosome
Any chromosome that is not a sex chromosome
Bacteriophage
A virus that targets a bacterial host
B lymphocytes
White blood cells that produce specific antibodies in response to specific antigens
Caspase
Proteinases which destroy a cell
Centrifugation
A process which uses centrifugal forces to separate components of a mixture
Chiasmata
The place where two homologous chromosomes come into contact with one another
Chordata
Sea squirts and vertebrates
Examples: birds, mammals, reptiles, amphibians and fish
Chromatography
A set of techniques which separate the components of a mixture
Civil engineering
A profession that is involved in the design and manufacture of infrastructure to improve standards of living
Clonal selection
Lymphocytes becomes 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
Colorimeter
A device that is used to measure the absorbance of a specific wavelength of light by a solution
Competitive exclusion principle
When two species are in intense competition with one another and the weaker of the two species becomes locally extinct
Conformation
The spatial, three dimensional arrangement of the atoms that make up a molecule
Crossing over
The process where the homologous chromosomes swap genetic material
Cysticercosis
A parasitic tissue infection
Definitive host
The host where the parasite reaches sexual maturity
Depolarisation
An electrical state in an excitable cell whereby the inside of the cell is made less negative relative to the outside than at the resting membrane potential
Ectoparasite
A parasite that lives on the surface of the host
Electrophoresis
A process which applies an electrical current across a gel to separate components of a mixture
Endoparasite
A parasite that lives inside the host
Examples: tapeworms and flatworms
Epidemiology
The study of the outbreak and spread of infectious diseases
Ethogram
A chart on which observed animal behaviours is recorded
Ethology
The study of animal behaviour
Eukaryotic
An organism with a membrane bound nucleus
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
Extra cellular
Outside the cell
Ferns
Flowerless plants that reproduce by producing spores and which have a vascular system
Fluorescence
The emission of light of a different wavelength to that which was absorbed
Fundamental niche
The niche that the organism occupies where there are no other species present competing for space or resources
Genetic drift
The random change in how frequently a particular allele occurs within a small population
G-protein
Proteins which act as molecular switches. They allow signals from outside the cell to be transmitted inside (involved in signal transduction). Their activity is regulated by their ability to bind and break down GTP to GDP. When GTP is bound and hey are ‘on’ and when GDP is bound they are ‘off’
Gravid proglottid
The segment of a tapeworm containing both male and female reproductive organs
Gymnosperm
Flowerless vascular plants that produce seeds for reproduction
Example: conifers
Haemocytometer
A device used to count cells
Herd immunity
Protection offers to non immune members of a population by sufficient numbers of immune individuals
Herd immunity threshold
The density of resistant hosts in a population required to prevent an epidemic
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 chromosome
Chromosomes of the same size, same centromere position and which carry the same genes at the same gene loci
Hybridoma
A cell formed from the fusion of a myeloma cell with an antibody- producing B cell
Hydrophilic
(Means water loving) a molecule of this type is electrically attracted to the polarity of the water molecules
Hydrophobic
(Means water hating) a molecule of this type is not electrically attracted to the polarity of water and is repelled away from the water molecule
Hyperpolarisation
A change in a cells membrane potential that makes it more negative
Immune surveillance
White blood cells patrol the body, recognising and destroying foreign pathogens
Immunoassay
Techniques which use antibodies linked to reporter enzymes to cause a colour change in the presence of a specific antigen
Imprinting
An irreversible process that occurs within a critical period of young bird development. It can also have an impact on mate choice later in life
Independent assortment
Takes place during meiosis 1 when homologous chromosomes pair up and line up at 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 increased blood flow, bringing white cells for defence
Intermediate 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
Intracellular
Inside the cell
Kinetochore
The point on a chromosome where the spindle fibre binds
K-selected
Larger organisms that usually produce lower numbers of offspring, providing more extensive parental care and have longer life spans
Lekking
Males display for females in a communal display area, then females choose a mate
Ligand
A substance which can bind to a particular a protein
Line transect
Line along which quadrants are placed or samples taken
Linked genes
Genes that are on the same chromosome
Liverworts
Flowerless, spore producing plants with flattened stems and overlapping leaves
Lymphocyte
A type of white blood cell which forms part of the immune system
Lysis
The bursting of a host cell, releasing many virus particles
Malaria
A serious human disease spread by mosquitoes that are infected by the plasmodium parasite
Meiosis
A special type of cell division where four haploid gametes are produced from one diploid gamete mother cell
Memory cells
Cloned lymphocytes that remain in the body to respond faster if the individual is exposed to the same antigen a second time
Mollusca
Molluscs which are greatly varied, with many characterised by the presence of a shell
Examples: snails and octopi
Monogamy
Where animals form breeding pairs, thus one male to one female
Monomer
A molecule that may bind chemically to other molecules to form a polymer
Mosses
Flowerless plants, lacking seeds and a vascular system
Mutation
Random change in DNA sequences within a population
Mutualism
Symbiotic relationship where both species benefit
Myeloma
A B-cell cancer cell
Natural killer cells
Lymphocytes responsible for destroying abnormal cells
Natural selection
Non-random process whereby certain alleles occur more frequently within a population because they confer a selective advantage
Nematoda
Round worms which show great variety. Many of which are parasitic
Examples: tapeworms
Opsin
A photoreceptor molecule found in the animal kingdom
Parasite
An organism is that gains food and shelter at the expense of the host
Parthenogenesis
Asexual reproduction whereby embryos develop from an unfertilised egg
Passive
A process which does not require energy
Phagocyte
White blood cell in non-specific defence, engulfing and destroying foreign antigens- may also present antigens to lymphocytes
Phagocytosis
Non specific defence where phagocytes engulf foreign antigens and digest them using digestive enzymes present in the lysosomes
Phosphorylation
The addition of a phosphate group to a molecule
Photon
A particle representing a quantum of light
Platyhelminthes
Flatworms which show bilateral symmetry with internal organs present, but lack a body cavity. Many of which are parasitic
Point count
Sampling technique used for birds
Pollinator
An organism that transfers pollen from the anther of one flower to the stigma of usually another flower
Examples: bees and hummingbirds
Polygamy
Usually where one male has access to mate with several females
Polymer
A large molecule, or macromolecule, composed of many repeated subunits, known as monomers
Polypeptide
A single chain of amino acids
Prosthetic group
A non-protein unit which is tightly bound to a protein that is necessary for its function
Proteinase
An enzyme which breaks down proteins by hydrolysis
Proteolytic
Substances which can break down proteins into smaller polypeptides or amino acids
Proton
A hydrogen ion
Random sampling
Individuals selected from the larger population must be chosen completely by chance
Realised niche
The niche that an organism occupies when there is competition form other species
Recombinant
The chromosome created when linked genes are separated during crossing over
Red queen hypothesis
A theory concerning co-evolution of a parasite and its host. An evolutionary arms race
Relative fitness
The ratio of surviving offspring of one genotype compared with other geneotypes
Resource partitioning
Where two species occupy different realises niches, allowing them to co-exist by compromising over resources
Retinal
A light sensitive molecule
Retrotransposon
The piece of DNA that carries out reverse transcription before being inserted into a new site in the genome
Retrovirus
A virus that contains RNA as its nucleic acid
Reverse transcriptase
An enzyme used by retrovirus to synthesise DNA that can be inserted into the host cell’s genome
r-selected
Smaller organisms that usually produce larder numbers of offspring, providing no parental care and having smaller life spans
Sanitation
Access to facilities for safely disposing of human waste such as urine and faeces
Satellite male
Male that sneaks to gain access to females
Schistosomiasis
Also known as bilharzias, a human disease caused by parasites living in fresh water in subtropical and tropical regions of the world
Sessile
Organisms that are fixed in position and cannot move
Sexual dimorphism
Physical difference between males and females of a species
Sexual selection
A non- random process, whereby certain alleles occur more frequently within a population because they are selected/ preferred by one sex
Sneaker
Male that gains access to mate with a female without the more dominant male knowing
Standard curve
A graph which can be used to determine the concentration is an unknown solution
Stratified sampling
Individuals are randomly selected from sub groups within a population
Symbiosis
An interrelationship between organisms of two different species, whereby at least one species benefits
Symport
Describes an integral membrane protein which is involved in simultaneously transporting two substances across the membrane in the same direction
Systematic sampling
Where the samples may be taken at regular/ preset intervals
Taxonomy
Grouping living organisms based in similarities and relatedness
Terrain
The physical geography of the land
Thylakoid
A membrane bound compartment found in the chloroplasts, containing photosynthetic pigments
T lymphocytes
Lymphocytes that destroy specific infected or damaged cells by bringing about apoptosis
Transmission
The spread of a parasite to a host
Vector
The means of transmitting a parasite
Vegetative propagation/ cloning
A form of asexual reproduction that takes place in some plants resulting in offspring that are genetically identical to the parent plant
Examples: bulbs and runners
Virulence
The deleterious effect that the parasite has on the host
Waterborne
Transmitted by water
