Keywords~ Flashcards
Define the term inheritance.
the transmission of genetic information from generation to generation
Define chromosome.
a length of DNA found in the nucleus of a cell; it contains genetic information in the form of many different genes
Assimilation
the uptake and use of nutrients by cells
Transmissible disease
a disease that can be passed from one host to another; they are caused by pathogens
Hormone
chemicals that are produced by a gland and carried in the blood, which alter the activities of their specific target organs
Population
a group of organsims of one species living in the same area at the same time
Ecosystem
a unit containing all of the organisms in a community and their environment, interacting together
Define the term diffusion.
The net movement of particles from a region of higher concentration to lower concentration caused by the random movement of particles
Define allele
Alternate form of a gene
Define sense organ
a group of receptor cells that are able to respond to a specific stimulus
Define tissue. Give an example
group of similar cells that work together to perform a particular function; EG: layer of cells lining the stomach which make enzymes
Define bacteria. What’s one strange thing about them?
unicellular organisms whose cells do not contain a nucleus, mitochondria or chloroplast but do photosynthesise
Define active transport
the movement of molecules or ions through a cell membrane from a region of lower concentration to a region of higher concentration (against the concentration gradient) using energy from respiration
Define double circulatory system
a system in which blood passes through the heart twice on one complete circuit of the body
Define gene
length of DNA that codes for one protein
homeostasis definition
the maintenance of a constant internal environment
Define excretion
the removal of waste products of metabolism and substances in excess of requirements
What is an organ?
group of tissues that work together to perform a particular function (several organs for organ system)
an onion bulb is even an organ
Define decomposer.
an organism that gets its energy from dead organic material
Define stem cell
Stem cells are unspecialised cells that can divide by mitosis to produce different types of specialised cells.They have the potential to become specialised themselves.
Describe what is meant by the term species.
A group of organisms that can reproduce to produce fertile offspring.
State what is meant by a monoculture.
an area of ground covered in a single crop in production with almost no other species present
Describe what is meant by the term catalyst.
catalyst is a substance that increases the rate of reaction and is not used up in the reaction.
Describe what is meant by a gene mutation.
random changes in the base sequence of DNA; can produce new alleles