Glossary II Flashcards
MHC
Proteins that may carry antigens within antigen-presenting cells to the cell surface membrane where they identify the cell as ‘foreign’, triggering the immune system
MSH
A hormone which activates melanocytes and cause them to make more melanin in response to uv light
Medulla oblongata
Part of the hindbrain which is responsible for heart rate, breathing and blood pressure
Micropropagation
The production of new plants from individual cells or small pieces of tissue using agar and nutrients
Myogenic
Muscle which is able to contract without being stimulated to do so by a nerve - e.g. The heart
Negative feedback
Many substances and systems in living organisms have a set level and negative feedback is the process whereby the departure from this set level results in changes which return it to the original level
Oncogene
A gene that codes for a protein that stimulates the cell cycle
Oxidative phosphorylation
A method of synthesising ATP from ADP in mitochondria in which oxygen acts as the final carrier in the electron transport chain
P wave
Depolarisation if the atria that leads to atrial contraction
Passive artificial immunity
Immunity that develops when a person is given ready made antibodies which help kill pathogens
Purkyne fibre
Specialised muscle fibres which conduct the electrical impulses which cause ventricular systole to
Rhizoid
A small root like structure used to anchor an organism
Saltatory conduction
The way in which a nerve impulse travels along a myelinated axon from one node of ranvier to another
Sigmoid curve
An s shaped line on a graph
Sliding filament theory
The theory that muscle contraction is the result of the relative movement of actin and myosin
