Unit 2 Test pt. 3 Flashcards
Homeostasis
Maintaining an internal enviroment.
Positive Feedback:
Changing from normal point and amplifing it
Negative Feedback:
Aiming for stabilization, trying to get back to normal
Active Diffusion Transport:
uses carrier molecule and energy to move molecules against concentration gradient.
*low to high concentration
Passive Diffusion Transport:
energy is not needed to move of molecules down the concentration gradient.
*high to low concentration
Synthetic Toxin:
Harmful
Natural Toxin:
Not Harmful
Endocytosis
Comes into the cell
Exocytosis
Exits the cell
Pinocytosis
Pinches off the cell
Factors effecting the Rate of Diffusion
- Difference in concentration between the inside and outside of the cell. The bigger the difference between concentrations, the diffusion will be faster.
- The size of the chemical substance. O2 is two atoms. Glucose is 24 atoms big. Protein is massive. Oxygen can easily diffuse across a cell membrane. Sugar can kind of, that’s why it’s assisted by a transporter protein to facilitate it. The proteins don’t move at all.
- Temperature. Higher temps = molecules move faster. ‘Nuff said.
- Whether the chemical substance is water-soluble or lipid soluble. The lipid soluble goes through faster because the cell membrane is phospholipids and can easily diffuse through a fatty membrane.
Temperature effect on enzyme activity and metabolic rate:
is slow at the lower and upper ends of a given temperature range, and highest at some optimum point.
Osmotic Pressure
- minimum pressure which needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane
- the measure of the tendency of a solution to take in water
Endocrine System:
Regulates the body: growth and develoment and produce chemicals and hormones.
Osmosis
Movement of water(only) across a membrane from an area of high concentration to an area of low concentration.
