B9: Animal physiology Flashcards
why does respiration occur
for cells to release energy
enzyme is catalyed by…
enzymes
so rate of respiration sensitive to temp +pH changes
energy from respiraiton used to fuel
- protein synthesis and making other new molecules
- active transport
- cell division
- muscle contraction.
aerobic respiration requires
oxygen
aerobic is more…+ releases….
efficent than anaerobic respiration
releases more energy
energy is in the form
ATP
in euk cells, aerobic respiratipn takes place
in mitochondria
in prok, aerobic respiration takes place
in cytoplasm
word equation for aerobic respiration
Glucose + Oxygen → Carbon Dioxide + Water + Energy (ATP)
anaerobic respiration occurs without
oxygen
anerobic respiration releases…
less energy than aerobic
but important fot cells that can’t obtsain sufficient o2
word equation for anaerobic respiration in animals
Glucose → Lactic acid + Energy (ATP)
lactic acid is… so must be….
toxic
removed
rate of respiration when exercising
increases
as muscle cells need more energy
for contraction
to produce movement
during exercise….
breathing rate increases
heart starts to beat faster
allowing more O2 to reach muscle cells
allows more aerobic respiraiton to take place + more CO2 to be removed
during exercies the body may….
break down glycogen stores
in liver + muscles
to get more glucose
what happens if cells dont get enough O2 during exercies
cells will start to use anaerobic respiration
produces lactic acid in muscles
causing pain + tiredness
explain oxygen debt
after exercies breathing rate may remain high
extra O2 taken in
to replenish oxygen debt required
to remove toxic lactic acid from body
what is the nervous system
rapid communicaiton system of bodies in animals
made of several diff types of cells
that use electrical impulses to send cellular messages
producing quick, short lived respones
the nervous system uses…
system of nervees
that connect organs + tissues
these link to CNS
which coordinates inputs from other nerves
neurone is…
one of the cells in the nervous system
nerves are made of
bundles of axons of neurones
what is the CNS
made of brain - protected by skull
spinal cord - collection of nerves running down spine
how are impulses send to and from CNS
nerves from receptors in sense organs bring impusles to spinal chord which then sends to brain for processing brain inteprets impulses \+ responds by sending impulse via spinal chord to to nerves connected to organs + tissues of body
what is a neurone description+ function
nerve cell
transmit electrical impulses
all neurones contain single nucleus in cell body
+ extensions of cytoplasm
allowing electical impulses to travel through them
diff types of neurones?
sensory
relay
motor
sensory neurones….
connect receptors (detect stimuli in environment) with CNS
relay neurones…
found in CNS
connect sensory + motor neurones
to allow communication to + from brain
motor neurones…
connect CNS to effectors
what are effectors
parts of body
that produce response
to electrical impulse
an axon is the
long section of neurone
through which electrical impulse can travel
axon is surrounded bt
myelin sheath
the myelin sheath
protects axon
makes impulse travel faster
dendrites
allow connections to be made to other neurones
what is a synapse
small gap between two neurones
allow neurones to transmit electrical impulses to each other.
also allow multiple neurones to connect with each other at once.
how do impulses cross synapse
electrical impulse travels along the axon of a neurone until it reaches the end of the neurone.
Here the impulse causes a chemical to be released into the synapse. -neurotransmitter
it diffuses from the axon across the synapse
to the neurone on the other side.
When reaches the surface of the dendrite, it binds to a receptor
which allows the electrical impulse to be regenerated. new impulse then travels down the axon of the other neurone.
This process happens very quickly.
what is a reflex arc used for
required in order to produce a quick reflex action.
to protect the body from harm
occur very rapidly.
they do not require processing in the brain.
describe the process of a reflex arc
receptor detects a stimulus.
receptor generates an electrical impulse
which passes to a sensory neurone.
electrical impulse passes down the axon of the sensory neurone to the spinal cord.
There the message crosses a synapse, using chemical neurotransmitters,
producing an impulse within a relay neurone
in the central nervous system.
The electrical impulse in the relay neurone connects via another synapse to a motor neurone.
the impulse progresses along the motor neurone
till it connects with an appropriate effector.
The effector- muscle -contract when it receives the impulse.
ontraction will move the body away from the source of harm.
