Glossary Flashcards
Abiotic
Physical/living factors
Active site
Position on the surface of an enzyme molecule to which specific substrate molecules can bind
Adaptation.
Feature of an organism that helps it to survive
Aerobic
Requires oxygen
Algal bloom
A seasonal abundance of algae
Allele
Different forms of the same gene
Alveoli
Tiny sacs in lungs that form the gas exchange surface
Amino acid
Building block of a protein molecule
Ammonium
NH4 - a nitrogen-containing waste product of decomposition
Anther
Male sex organ within flower that produces pollen grain
Antibody
Protein that is involved in defence in animals
Aorta
Main artery that carries oxygenated blood away from the heart
Aseptic techniques
Laboratory procedures designed to prevent contamination of pure cultures of microorganisms
Atria
Upper chambers of heart which receive blood from veins
Bases
Form the genetic code of DNA and mRNA
Biome
Region of planet with characteristic climate, flora and fauna
Bond
Chemical link between atoms in a molecule
Capillaries
Tiny blood vessels with walls one-cell thick where exchange of materials occur
Carnivore
Consumer which eats other animals
A, G, T, C & U
Letters that represent the names of the bases of DNA and mRNA
Cartilage
Flexible tissue forming C-shaped rings in the trachea to keep the airway open
Catalyst
A substance that speeds up a chemical reaction by reducing the energy required to start it.
Cellulose
Structural carbohydrate of which plant cell walls are composed
Chromatid
Replicated copy of chromosome visible during cell division
Chromosome
Structure containing hereditary material composed of DNA that codes for the characteristics of an organism
Competition
Interaction between organisms seeking the same limited resources
Consumer
Animal which eats ready-made food
Cytoplasm
Jelly-like liquid containing cell organelles and the site of biochemical reactions
Digestion
Breakdown of large, insoluble food molecules into smaller, soluble ones
Discrete
Variation that is clear-cut and observable as categories
Donor
Organism from which the genetic material is obtained for transfer to another species
Endocrine gland
Gland that produces and releases a hormone directly into the blood
Fertilisation
Fusion of the nuclei of haploid gametes
Fertiliser
Chemical added to the soil to improve plant growth or crop yield
Gene
Small section of DNA that codes for the production of a specific protein
Genetic engineering
Artificial transfer of genetic information from one donor cell or organism to another
Genetically modified
Term given to a cell or organism that has had its genetic code altered, usually by adding a gene from another organism
Glucose
Simple sugar used as a respiratory substrate for the production of ATP
Grazing
Method of feeding on plant by herbivores
Guard cells
Found on either side of stoma; they control gas exchange in leaves by controlling the opening and closing of the stoma
Haemoglobin
Pigment in red blood cells that transport oxygen as oxyhaemoglobin
Hormone
Protein released by an endocrine gland into the blood to act as a chemical messenger
Lacteal
Central vessel in the villi responsible for the absorption of the products of fat digestion
Leaf epidermis
Skin-like tissue forming the upper and lower covering of leaves
Lignin
Carbohydrate material lining the xylem vessels and providing strength and support
Lymph
Liquid that circulates within a mammals body, transporting the products of fat digestion from the lacteals
Medium
Solid or liquid nutrient agar or broth used to control microorganism
mRNA
Substance that carries a complementary copy of the genetic code from the DNA to the ribosomes
Minerals
Nutrient ions essential for healthy growth
Mitosis
Division of the nucleus of a cell that leads to the production of two genetically identical daughter cells
Motile
Able to move under its own power
Mutation
A random and spontaneous change in the structure of a gene, chromosome or number of chromosomes; only source of new alleles
Nitrogen cycle
Sequence of events or processes involved in the recycling of nitrogen
Nitrogen-fixing bacteria
Bacteria found free living in the soil or in the root nodules of some plants (legumes) that convert nitrogen gas to nitrate
Omnivore
Consumer which eats a mixture of plants and animals
Optimum
Conditions such as temperature and pH at which an enzyme works best
Organ
Group of different tissues that work together to carry out a particular function e.g heart/lungs
Organelle
Membrane-bound compartment with a specific function in animal, plant and fungal cells
Ova
Female gametes produced by ovaries in animals (sing. Ovum )
Ovule
Structure containing a female gamete, produced by ovaries in plants
Pancreas
Organ responsible for the production of digestive enzymes and the hormones insulin and glucagon
Parasitism
An interaction between two organisms in which one benefits and the other is harmed
Passive transport
Movement of molecules down a concentration gradient without the need for additional energy, e.g. Diffusion/ osmosis
Peristalsis
Waves of muscular contraction responsible for the movement of food through the oesophagus/intestines
Phospholipid
Fat or oil with molecules composed of fatty acids and glycerol
Pitfall trap
Sampling technique used to trap animals living on the soil surface or in leaf litter
Plasmid
Circular genetic material present in bacterial cells and used in genetic engineering/modification.
Polygenic
Inheritance determined by the interaction of several genes acting together
Precipitation
Water such as rain/snow/sleet/hail/dew
Predation
Obtaining food by hunting and killing prey organisms
Protein
Substance composed of chains of amino acids and containing the elements carbon, hydrogen, oxygen and nitrogen
Quadrat
Square frame of known area used for sampling the abundance and distribution of slow or non-moving organisms
Radiation
Energy in wave form such as light, sound, heat, X-rays, gamma rays
Receptor cell
Cell that can detect stimuli inside or outside the body
Receptor protein
Cell surface protein which allows a cell to recognises specific substances
Recipient
Cell or organism that receives genetic material from a donor cell or organism
Reflex arc
Pathway of information from sensory neuron through relay neuron directly to motor neuron
Respirometer
A device to measure respiration rates in living tissue
Root epidermis
Outer layer of cells of a root
Root nodule
Small swelling on the roots of plants such as peas, beans and clover that contain nitrogen-fixing bacteria
Selection pressure
Factor such as predation or disease that affects a population, resulting in the death of some individuals and survival of others
Selective advantage
An increased chance of survival for an organism because of possession of favourable characteristics
Speciation
Formation of two or more species from an original ancestral species
Starch
Storage carbohydrate in plants
Stem cell
Unspecialised cell capable of dividing into cells that can develop into different cell types
Stimuli
Changes in the environment detected by receptor cells that trigger a response in an organism
Target organ
Organ with receptor molecules in its cell surface that recognise a specific hormone
Toxicity
Poison level
Transpiration
Evaporation of water through the stomata of leaves
Ultrastructure
Fine structure and detail of a cell and its organelles revealed by an electron microscope
Valve
Structure in veins that prevents the backflow of blood
Vector
Method of transferring genetic material from a donor to a recipient e.g. Viruses/bacterial cells/plasmids
Ventricles
Lower chambers if the heart that receive blood from the atria and pump into arteries
Villi
Finger-like projections of the small intestines lining providing a large surface area for absorption of food
Zygote
Fertilised egg cell
