Essay on Physiology: Membrane Potential

Submitted By bneedham116
Words: 3766
Pages: 16

Chapter 3

The provides an overview of the topics we will go over during. Please realize the importance of not only knowing the individual terms, but linking them to larger concepts, and then linking concepts together.

METABOLIC PATHWAYS

• Terms associated with glucose usage and storage o Glycogen- stored in the muscle and liver and can be made into ATP at a later time; glycogen in the liver can be turned back into glucose to supply other tissues o Glycogenolysis- process of breaking down glycogen o Gluconeogenesis- formation of new glucose by taking glycogen to break down into glucose with extra phosphate attached onto it, then break down into glycogen • Fat metabolism o Adipose tissue- made by adipose cells; main areas where we store fats o Adipocytes- cell specialized for triglyceride synthesis and storage
Beta oxidation- Beta oxidation: way of breaking down fatty acids. Through this whole complex mechanism we end up taking off a piece of fatty acid at a time and make it into something else that goes into the Krebbs Cycle.

• Protein Metabolism o Proteolysis- process of breaking down proteins o Protease- enzyme that breaks down proteins o Keto acids- class of breakdown products formed from the deamination oxidative acids. o Oxidative deamination- taking an amino group off of an amino acid and form ammonia and a keto acid Oxidative deamination: take one amino acid and make it into another one and can basically break down amino acids that ultimately wind up being how to get rid of excess amino acids in the system. Excreted through the process of urea.

o Transamination- take an amino acid and add a keto acid and form a new amino acid o Urea- end product that we can make from amonia

Chapter 4

The provides an overview of the topics we will go over during. Please realize the importance of not only knowing the individual terms, but linking them to larger concepts, and then linking concepts together.

• Diffusion- all about gradients; all based on random movement o Simple Diffusion- reaching an equilibrium ▪ Flux- movement across something (molecules) ▪ Net flux moving in which ever the sum of the two different directions ▪ Diffusion equilibrium- start off with lots of something in one area and a little on another area but over time it equals out. Requires no energy

o Diffusion Through Membranes- the rates at which molecules diffuse across membranes are a thousand to a million times slower than the diffusion rates of the same molecules through a water layer of equal thickness; membranes act as barriers; oxygen, CO2, faty acids and steroid hormones are examples of non polar molecules that diffuse rapidly through the lipid portions of membranes; liophilic substances move through easily ▪ diffusion through ion channels- ion channel is the hole in the middle of a glob of amino acids that ions can go through ▪ hydrophilic- water loving; generally polar ▪ hydrophobic- water fearing; generally non polar; major factor limiting diffusion across a membrane
Diffusion through lipid bilayer Diffusion through lipid bilayer: small and generally going to be nonpolar and can go through membrane through the cell so anything that is polar cannot get through
Diffusion through protein channels Diffusion through protein channels: something that is polar needs a special channel to go through. Needs some kind of transporter to let it get through the cell. • Electrical Forces o Different types of channels (K+, Na+, Cl-) o Electrochemical gradient- idea that inside wants to get out and outside wants to get in because of electrical charge attraction. ▪ Membrane