animal physiology (responding to stimuli) Flashcards
what challenge to animals must respond to both internal and external stimuli? and why?
homeostasis
to maintain protein/enzyme functions and maintain metabolism
what is homeostasis
ability to respond and react to maintain internal conditions
what are the 3 important conditions in the environment for cellular function?
- Proper fluidity of plasma membrane
- Confirmation of protein structure
- Composition of the cytoplasm
what 5 factors can change?
- Body temperature
- Concentrations of O2 and CO2
- pH
- Ion concentration
- Glucose
what are 5 contributions of the organ systems to homeostasis?
- Respiratory & Cardiovascular
- Respiratory, Cardiovascular & Renal
- Renal
- Gastrointestinal & Liver
- Endocrine & Nervous
how does Respiratory & Cardiovascular contribute to homeostasis?
regulate ECF [O2], [CO2]
amount of O2 changes
how does Respiratory, Cardiovascular & Renal contribute to homeostasis?
regulate ECF pH
how does Renal contribute to homeostasis?
regulates ionic composition and ECF osmolarity
ion concentration/osmosis
how does Gastrointestinal & Liver contribute to homeostasis?
regulate nutrient availability
blood sugar
how does Endocrine & Nervous contribute to homeostasis?
integrate and coordinate all of the above
regulates bodies homeostatic conditions
How will an animal body know there is a change away from the normal set-point? what two things are needed and what does this allow?
- A monitor must be in place that detects change
- The monitor must also be linked to a means to influence the system
This detection and influence to adjust is an animal’s ability to respond
some animals are better equipped than others
What are the two mechanisms for maintaining homeostasis?
- Negative feedback
2. Positive feedback
what is Negative feedback?
maintenance of set/’fixed’ conditions
what is positive feedback?
bringing homeostasis back to normal
In order for feedback to work it must have a means to monitor conditions, what does it need?
Specialized receptors
what are two kinds of Specialized receptors?
- Exteroceptors
2. Interoceptors
what are Exteroceptors?
External Environment, Five Senses
what are Interoceptors?
Within the Body
Limb Position
Body Temperature
Blood Pressure
what are 4 types of sensory receptors?
- Chemoreceptors
- Photoreceptors
- Mechanoreceptors
- Thermoreceptors
what are Chemoreceptors? and what is a specific type of chemoreceptors?
respond to nearby chemicals
specific type- Nociceptors
what are Photoreceptors?
respond to light energy
what are Mechanoreceptors?
respond to mechanical forces such as pressure
what are Thermoreceptors?
stimulated by temperature changes
what are Nociceptors?
(pain receptors) – chemoreceptors that respond to chemicals released by damaged tissue
what are two main divisions of Vertebrate Neuromuscular System?
- Central nervous system (CNS)
2. Peripheral nervous system (PNS)
what does the Central nervous system (CNS) consist of ?
Brain and spinal cord
what does the Peripheral nervous system (PNS) consist of?
Nerves and ganglia (collections of cell bodies)
what three components make up the Neuron structure?
- Cell body
- Dendrites
- Axon
what is the Cell body of a neuron?
main cell where nucleus and most organelles reside
what is the Dendrites of a neuron?
many short extensions that carry impulses to a cell body- they take information in
what is the Axon of a neuron?
(nerve fiber) – single, long extension that carries impulses away from the cell body- carries info away from cell
what are Axon terminals within a neuron?
ends of the
neuron which will transmit
signal to other neurons
branches into a series of additional terminals
what is the Synapse within a neuron?
location where axon terminals of one neuron will meet the dendrites of the next neuron- they excite the next cell because terminals don’t touch
what are unipolar neurons?
1 large axon, specialized and strong- they relay informations and send it away
what are bipolar neurons?
inside the central nervous system- they interpret information and sends info via axon
what are multipolar neurons?
interacts with sensors
what are three types of neurons?
- Sensory (unipolar)
- Interneuron (bipolar)
- Motor (multicellular)
what are Sensory (unipolar) neurons?
takes impulses from sensory receptor to CNS
what are Interneuron (bipolar) neurons?
receives information in the CNS and sends it to a motor neuron
what are Motor (multicellular) neurons?
takes impulses from the CNS to an effector (i.e., gland or muscle fiber)
what are the 4 functions of neurons?
- Collect information
- Make decisions about the information
- Transmit the information
- Transfer information
what does the Collect information function of a neuron do?
Receive information from external/internal environment or other nerve cells
what does the Making decisions about the information function of a neuron do?
Integrate information and decide not to pass on information or produce an output signal
what does the Transmitting of the information function of a neuron do?
Produce and conduct the signal (electrochemically)
what does the Transferring of information function of a neuron do?
Transmit the signal to other nerve cells, glands, muscles, etc.
