Bio topic 6

Taxis (tactic response)

directional movement in response to a stimulus

kinesis (kinetic response)

non directional movement in response to a stimulus. The intensity of the stimulus affects the response

effector

a cell that brings about a response to a stimulus to produce an effect

simple reflex - what is it and where does it go through

rapid, involuntary response to a stimulus. Through spinal cord but not conscious part of brain

Tropism

the response of a plant to a directional stimulus

Structure of a pacinian corpuscule

Sensory nerve ending wrapped in layers of connective tissue called lamellae

bipolar neurone

connect photoreceptors to optic nerve that takes impulses to brain

visual acuity

ability to tell apart points that are close together

peripheral nervous system

made up of the neurones that connect the CNS to rest of body

Bundle of HIS

Group of muscle fibres responsible for conducting the waves of electrical activity between the ventricles and apex of heart

purkyne tissue

carries the waves of electrical activity into the muscular walls of the ventricles so they contract simultaneously

where are baroreceptors located

aorta and carotid arteries

where are the chemoreceptors located

aorta, carotid arteries and medulla

Myelin sheath

electrical insulator made of Schwann cells

When the electrical impulse jumps from node to node

saltatory conduction

what are synapses that use acetylcholine called

cholinergic

Summation

when the effect of neurotransmitters released from many neurons is added together

spatial summation

when 2 or more presynaptic neurones release their neurotransmitters at the same time onto the same postsynaptic neurone

temporal summation

when 2 or more nerve impulses arrive in quick succession from the same presynaptic neurone

Neuromuscular junction

specialised cholinergic synapse between a motor neurone and a muscle cell

What is the contracting muscle called in an antagonistic pair

agonist

what is the relaxing muscle called

antagonist

Bond that forms between myosin head and actin filament

actin myosin cross bridge

Pcr

phosphocreatine

What is homeostasis

maintenance of a stable internal environment

equation for pH

-log(H+)

glycogenesis

glucose to glycogen activated by insulin

glycogenolysis

glycogen to glucose activated by glucoagon and adrenaline

gluconeogenesis

glycerol/amino acids to glucose activated by glucagon

What does adrenaline do

activates glucagon secretion and inhibits insulin secretion

explain second messenger model

Adrenaline/glucagon bind to specific receptors and activate enzyme called Adenylate cyclase. This converts ATP to cAMP. cAMP acts as second messenger and activates protein kinase which activates enzymes to break down glycogen into glucose

diabetes

when blood glucose concentration can’t be controlled properly

Glomerulus

bundle of capillaries inside bowman’s capsule