Biology key words

habitat

place where an organism lives

population

all members of a single species which live in same area

community

all populations of different species interact together in same habitat

ecosystem

community of organisms and the habitat it lives

producer

organism that converts light energy into organic molecules

trophic levels

stage in a food chain made up of a particular group of organisms

decomposers

organisms which feed on and break down dead organism and waste materials

biotic factors

living features of an ecosystem

abiotic factors

the non living features of an ecosystem

apoplast pathway

through non living part of the cell, cell wall is absorbant so H20 can diffuse through carrying solutes along a pressure gradient

symplast pathway

living part of the cell, cytoplasms of neighbouring cells connect through plasmodesmata

plasmodesmata

small channels in cell walls

centrioles

separate chromosomes during cell division, small hollow cylinders of microtubules

microtubules

tiny protein cylinders provide cells shape and keeps organelles in place, part of cytoskeleton

histones

proteins in chromosomes

lamellae

thylakoid membrane that links grana

phospholipid bilayer

made of phospholipids found in cell membrane, allows cell to be permeable

triglycerides

energy storage molecules, insoluble so H20 doesn’t make them swell, long hydrocarbon tails contain lots of energy

cholesterol

regulate fluidity by interacting with phospholipid bilayer

nucleotides

made from pentose sugars, nitrogenous base + phosphate group, make up RNA + DNA

peptides

short chain of amino acids joined together by peptide bonds

cofactors

inorganic molecules, help enzyme and substrate bind together but not used up in reaction

coenzyme

organic molecules, participate in reaction + act as carrier by moving chemical groups between different enzymes

end product inhibitor

final product in a metabolic pathway that prevents an enzyme that acts later on in the pathway

xylem

transport mineral ions + H20, long, tube like structure formed by vessel elements

cartilage

connective tissue found in joints, supports + shape things

continuous variation

individuals in a population vary with range, no categories

discontinuous variation

2 or more distinct categories, each individual falls into one category, no intermediates

partial pressure of oxygen

concentration of oxygen in a mixture of gases

chloride shift

chloride ions diffuse into red blood cells to compensate loss of hydrocarbonate ions that diffuse out + are transported to blood plasma

synthetic biology

using technology to design and make artificial proteins cells and organisms

species richness

number of different species in an area

primary response

infected with pathogen for the first time, slow process as it takes time for B cells to activate and divide into plasma cells

secondary response

when someone is infected with a pathogen for the seconds time, T memory cells divide into T killer cells, B memory cells divide into plasma cells, much quicker process

isomer

molecules that have the same molecular formula but atoms are linked in a different sequence, give molecules different chemical properties

communicable diseases

diseases that can be passed from one organism to the other

pathogen

microorganism that can cause disease

vectors

organisms that transmit a pathogen from one organism to the other

parasite

organism that lives in or on another species and benefits by depriving nutrients at the others expense

endemic

disease that is always present in the population

epidemic

large increase of number of cases in a population

pandemic

epidemic occurs on large scale, crosses international borders

active immunity

body can make own antibodies after being stimulated by an antigen

passive immunity

ready made antibodies that have been produced by another organism are introduced into the body.

personalised medicine

different genetic profiles respond differently to the same drugs, DNA used in the treatment plan

conjugated protein

globular protein that contains a prosthetic group

magnification

size of image compared to actual size of specimen

resolution

ability to distinguish 2 close points as seperate in finer detail

polypeptide

chain of amino acids linked by peptide bonds to form proteins

Polysaccharides

long chains of carbohydrate molecules joined by glycosidic bonds

anabolic reaction

building up reaction

catabolic reaction

going down

competitive inhibitor

compete with substrate to bind to enzymes active site and prevents substrate from binding to it

non- competitive inhibitor

bind to enzymes allosteric site causing active site to change shape

isotomic

solute concentration same inside and outside of the cell

antigen presenting cell

phagoctye approaches pathogens antigen and sticks it to its surface, stimulating production of other immune system cells

phagocyte

type of white blood cell that carries out pagocytosis

mucous membranes

protect body openings exposed to the environment

thermoregulation

temperature in the body

osmoregulation

water potential in body fluids

hormone

chemical messenger produced by endocrine gland, they are long lasting and used in distal areas

gland

group of cells that produce and release one or more substances through secretion

aldosterone

regulates sodium, potassium and water balance, impacts blood volume and pressure

cortisol

stress hormone, regulates metabolism of glucose, protein and fats for energy

sympathetic nervous system

releases adrenal medulla hormones, like adrenaline and noradrenaline, when in emergency situations

islets of langerhans

found in endocrine gland, produces insulin and glycogen

glycogenolysis

glycogen in liver and muscle broken down into glucose

gluconeigenesis

production of glucose from non carbohydrate sources

glycogenesis

production of glycogen to be stored

glycolysis/ respiration

glucose used by energy

negative feedback

counteraction of an effect by its own influence

genome

all the genetic material in an organism

introns

non coding regions of DNA removed from mRNA before being translated into a polypeptide chain

gene

sequence of DNA that codes for a polypeptide

alleles

version of a gene

karotype

type of gene testing, looks at all chromosomes of an individual

telomere

non coding region of DNA, act as protective caps that prevent ageing

centromere

non coding region of DNA, in the centre + helps cells divide

gene locus

location of gene on chromosome

sequencing DNA

sequences of nitrogenous bases

restriction endonucleus

bacteria that makes long DNA strands shorter by chopping them up so they are more manageable

plasmid

small ring of double stranded DNA

DNA ligase

forms phosphodiester bonds

binary fission

reproduction and replication for plasmids

primers

short single stranded DNA that is artificially produced, complementary to ends of region that is amplified

ring rot

damages leaves, tubers and fruit, no cure

potato late blight

hypahe of fungi penetrate host cell, damage fruits, leaves and tubers, resistant strains but no cure

black sigatoka

attacks and destroys leaves, hyphae penetrates and digest cells turning them black, fungicide controls spread but no cure

tobacco mosaic virus

damages fruite, tubers and leaves, resistant strains

tuberculosis

destroys lung tissue and suppress immune system to fight off other diseases, curable

bacterial meningitis

infection of protective membranes on brain surface can spread to rest of body, antibiotics and vaccines prevent it

HIV

gradually destroys immune system, no cure but drugs can slow process

influenza

infection of ciliated epithelium in gas exchange system so airway is open to infection

malaria

parasite reproduces in female mosquito then passed on, vaccines yearly

athletes foot

form of ring worm, grows in warm, moist skin between toes

oncotic pressure

tendency of water to move into blood by osmosis as a result of plasma proteins

elastic fibres

composed of elastin, can stretch and recoil, gives vessel walls flexibility

smooth muscle

contracts or relaxes, changes size of lumen

lumen

channel within the blood vessel

collagen

structural support to maintain shape and volume of the vessel