physiology - organelles and homeostasis Flashcards
what is negative feedback
the response of changing conditions by turning the condition back to its set point
eg temperature regulation
components of negative feedback
- Controlled variable
- Sensor
- Integrator
- Effector
- Compensatory response.
what does each component mean?
- stimulus
- informs control centre
- sends instructions to the effectors
- this brings out a reponse
- this allow the variable to be normal again
example of each component : decrease in temperature
- Controlled variable - temp
- Sensor - nerve cells
- Integrator - temperature control centre = hypothalamus
- Effector -skeletal muscles
- Compensatory response -heat production
what is positive feedback eg
reinforces a change in a controlled variable
eg child birth
functions of cells (5)
- Perform chem reaction that give en to cell
- Reproduce
- Exchange material with surrounding environment
- Sense and respond to changes in environment
- synthesise cellular components
what is endoplasmic reticulum
network of membranes inside a cell
continuous with cell membrane
Endoplasmic reticulum (ER)
- important for
- membrane
- protein synthesize
- encloses space and continuous with nuclear envelope
types of endoplasmic reticulum
rough ER which is found on ribosomes
smooth ER … no ribosomes
Golgi Apparatus:
location
function
inbetween ER and cell membrane
process and package molecules for transport
The Mitochondrion function
energy production from glucose
produces ATP
role of protein….
- in the cell
- in membrane
- outside cell
- enzymes and structure
- transport and structure
- digestive enzymes, hormones
Protein Synthesis & Sorting
uptake in amino acids in RER
golgi (packaging)
vacoules (storage)
membrane (released)
function of cytoskeleton
help cell maintain shape and internal organization
types of cytoskeleton
mircofilaments
intermediate filaments
microtubules
