Bones
Provide a firm anchorage for muscles. They also act as levers changing the size or direction of forces generated by muscles.
Muscles
Provide the force needed for muscle contraction.
Nerves
Co-ordinates muscle contraction so that it is stimulated to contract at precise
times.
Diffusion
The passive movement of particles from a region of high concentration to a region of low concentration.
Osmosis
The passive movement of water molecules, across a partially permeable membrane, from a region of lower solute concentration to a region of higher solute concentration.
Denaturation
A structural change in a protein that results in the loss (usually permanent) of its biological properties.
Cell respiration
The release of energy in the form of ATP from the controlled breakdown of organic compounds within the cell.
Gene
A heritable factor that controls a specific characteristic.
Allele
One specific form of a gene, differing from other alleles by one or a few bases only and occupying the same gene locus as other alleles of the gene.
Gene Mutation
A change in the sequence of base pairs found on a DNA molecule.
Homologous Chromosomes
Chromosomes that each have a corresponding chromosome from the opposite-sex parent. A pair of chromosomes with the same genes but not necessarily the same alleles of those genes
Genotype
The alleles of an organism.
Phenotype
The characteristics of an organism.
Dominant allele
An allele that has the same effect on the phenotype whether it is present in the homozygous or heterozygous state.
Recessive allele
An allele that only has an effect on the phenotype when present in the homozygous state.
Codominant alleles
Pairs of alleles that both affect the phenotype when present in a heterozygote.
Locus
The particular position of a gene on homologous chromosomes.
Homozygous
Having two identical alleles of a gene.
Heterozygous
Having two different alleles of a gene.
Carrier
An individual that has a recessive allele of a gene.
Test cross
Testing a suspected heterozygote by crossing it with a known homozygous recessive.
Sex linkage
When genes are found on one of the two types of sex chromosomes.
Clone
A group of genetically identical organisms or a group of cells derived from a single parent cell.
Species
A group of organisms that can interbreed and produce fertile offspring.
Habitat
The environment in which a species normally lives or the location of a living organism.
Population
A group of organisms of the same species who live in the same area at the same time.
Community
A group of populations living and interacting with each other in an area.
Ecosystem
A community and its abiotic environment.
Ecology
The study of relationships between living organisms and between organisms and their environment.
Autotroph
An organism that synthesizes its organic molecules from simple inorganic substances.
Heterotroph
An organism that obtains organic molecules from other organisms.
Consumer
An organism that ingests other organic matter that is living or recently killed.
Detritivore
An organism that ingests non-living organic matter.
Saprotroph
An organism that lives on or in non- living organic matter, secreting digestive enzymes into it and absorbing the products of digestion.
Trophic level
Step in the movement of energy through an ecosystem; an organism's feeding status in an ecosystem.
Evolution
the cumulative change in the heritable characteristics of a population.
Pathogen
An organism or virus that causes a disease.
Resting potential
The electrical potential across the plasma membrane of a neuron that is not conducting an electrical impulse.
Action potential
The reversal and restoration of the electrical potential across the plasma membrane of a neuron as an electrical impulse passes along it
Transpiration
The loss of water vapour from the leaves and stems of plants.
Linkage group
all those genes on a particular chromosome.
Polygenic Inheritance
the transmission of a characteristic that is influenced by several genes.
Active immunity
Immunity due to the production of antibodies by the organism itself after the body's defence mechanism have been stimulated by antigens.
Passive Immunity
Immunity due to the acquisition of antibodies from another organism in which active immunity has been stimulated, including via the placenta or by injection of antibodies.
Excretion
The removal from the body of the waste products of metabolic pathways.
Osmoregulation
The control of the water balance of the blood, tissue or cytoplasm of a living organism.
Biomass
the total mass of dry organic matter in an ecosystem
Biomagnification
a process in which chemical substances become more concentrated at each trophic level.
Partial pressure
The pressure exerted by a particular gas in a mixture of gases.
Biological control
using a predator or parasite to control a pest species
a high vlue of D in Simpson's Index suggests...
a stable/well-established/ancient ecosystem
when asked to 'outline the use of simposons deiveristy index in...' always start with...
simpsons index is a measure of the species richness of an ecosystem. the higher the index the greater the diversity
ecological succession
a series of changes to an ecosystme, caused by complex interactions between the community of living organisms and the abiotic environment. eventually results in a climax community
in situ conservation
conservation carried out in the organism's natural habitat
characteristics of r strategists
small body size, short life span, early maturity, investing more resources into producing more offspring, reproducing only once
characteristics of K strategists
long life span, late maturity, producing few offspring, reproducing more than once, investing more resources into development
example of organism that switched strategies
Drosophilia
example of r strategist
lemming, Lemmus lemmus
example of k strategist
lion, Pathera leo
abiotic factors affecting plant distribution
temperature, rainfall, light, soil pH, mineral nutrients, salinity
factors affecting distribution of animal species
food supply, temperature, breeding sites, territory, water
explanation of food source as factor affecting distribution of animal species
many animals have specialist requirements e.g. hummingbirds are specialist nectar feeders
explanation of breeding sites as factor affecting distribution of animal species
many animals have specialist requirements e.g. low-eared bats need caves. loss of breeding sites can lead to extinction
explanation of territory as factor affecting distribution of animal species
some animals have specialist territory requirements for obtaining food and breeding e.g. tigers. insufficient territory can lead to extinction
explanation of water as factor affecting distribution of animal species
water may be needed as a permanent habitat e.g. fish or for breeding e.g. amphibians. some animals are specialised to live in very dry areas e.g. bactrian camel.
definition: competition
when two or more species compete for a paricular resource
definition: predation
a predator killing its prey
definition: mutualism
a relationship between two different species where both species benefit from the relationship
definition: parasitism
a relationship between two different species where one species benefits and the other is harmed
example: mutualism
The clownfish Amphiprion percula and sea anemone Heteractis magnifica. Sea anemone provides shelter and protection with its sting for the clownfish. Clownfish draws in other fish that the sea anemone can sting and digest.
example: parasitism
The fish Encheliophis vermicularis lives inside the sea cucumber Bohadschia argus and comsumes its gonads.
Fundamental niche
The potential mode of existence of a species, given its adaptations of the species.
Realised niche
The actual mode of existence of a species, which results from its adaptations and competition with other species.
characteristics brysophyta
mosses and such like - no roots or cuticle, spores produced in capsules
characteristics filicinephyta
ferns - roots, leaves in fronds, cuticle on leaves, not woody, spores produced in structures called sporangia
characteristics coniferophyta
conifers - roots, stems, leaves, woody stems, produce seeds
characteristics angiospermophyta
flowering plants - can from woody tissue, produce seeds
characteristics porifera
sponges - lack tissues and organs, no special shape
characteristics cnidaria
jellyfish and sea anenomes - two forms medusa and polyp, radial symmetry
characteristics platyhelminthes
flatworms- bilaterally symmetric, mouth but no anus, rudimentrary head
characteristics annelida
sedmented worms - segmented body, bilaterally symmetric, mouth and anus
characteristics mollusca
snails, slugs etc
characteristcs arthropoda
bilaterally symmetric, hard exoskeleton, segmented
example of competitive inhibition
disulfiram inhibitor, acetaldehyde substrate, aldehyde dehydrogenase enzyme
example of non-competitive inhibition
nerve gas Sarin inhibitor, acetylcholine substrate, acetylcholinesterase enzyme
example of allostery
enzyme phosphorylase used to remove one glucose phosphate from glycogen for glycolysis, which produces ATP. When there is abundance of ATP e.g. during rest, there is no need for more atp. when there is abundance of AMP e.g. during exercise, there is need
two examples of food chain
phytoplankton --> copepod --> herring --> tuna;
genome
the whole of the genetic information of an organism