biol 2410

What is physiology the study of?

The normal functioning of a living organism and it's component parts

What does physiology focus on studying?

Structure and function relationships, chemical and physical reactions, and living organisms possess emergent properties (a non-linear interaction)

What defines whether something is alive? (4)

1. Made of one of more cells

2. regulates internal environment

3. Responds to stimuli

4. Capable of reproduction

Why is physiology important?

Leads to tx of diseases, aids in the understanding of how organisms cope with environmental stressors

What are the 5 themes in physiology?

1. The closeness of structure and function

2. Homeostasis and control systems

3. Info flow coordinates body function

4. the need for nrg

5. evolution

What is homeostasis?

The ability to maintain a RELATIVELY constant internal environment even when the external environment is variable

What are the homeostatic parameters?

1. Temp

2. pH

3. Salinity ([conc] of ions and other solutes)

4. O2 and CO2

5. Nutrients

What does homeostasis not mean?

Equilibrium, never changing,

What do homeostatic control systems do?

Monitor and Adjust regulated variables

What is a biomolecule?

An organic molecule that is commonly associated with life:

Carb, Lipid, Nucleic Acid, Proteins

What is the general formula of a carbohydrate?

CnH2nOn

Are carbs hydrophobic or hydrophilic?

Most are hydrophilic.

What are carbs used for?

Structure and Nrg:

-glucose for energy in eukaryotic cells

-plants and arthropods as the structure

-for the modification of proteins and lipids

What is the structure of a nucleotide?

1 (or more) phosphate groups, a 5-carbon sugar, and a nitrogenous base

Adenosine Triphosphate is the ________________ of nrg storage in most organisms.

Basic Molecule

What is Guanosine Triphosphate an nrg source for?

Many physiological chemical reactions.

What do hydro_______ lipid molecule mostly contain?

hydrophobic -- carbon, hydrogen, few oxygen, nitrogen, phosphorus

What are the 5 types of lipid molecules?

• Fatty Acids

• Glycerides

• Phospholipids/ Sphingolipids

• Steroids

• Eicosanoids

What are the roles of lipid molecules?

Structure of the cell (waterproof and pliable)

Nrg source

Communication

What is the difference between saturated and unsaturated fatty acids?

Saturated = no double bonds in a straight chain

Unsaturated = double bonds in a kinky chain

Which functional group(s) do fatty acids have?

Carboxyl

What are glycerides?

A derivative of fatty acids that attach glycerol to the carboxyl group of a fatty acid.

What are phospholipids?

A derivative of glycerides that attach a phosphate and 'r' group to a diglyceride.

Which parts of a phospholipids are hydrophilic and hydrophobic?

The head (r + phosphate + glycerol) is the hydrophilic part and the tail (fatty acids) is the hydrophobic part.

Which shapes do Micelles, Liposomes, and Phospholipid bilayers create?

Droplets (half spheres)

Droplet with a aqueous centre

Sheet

What are sphingolipids?

An attachment of a sphingosine (that extends farther than fatty acids) in replacement of glycerol and 1 of 2 fatty acids in a phospholipid.

How would you change a phospholipid or sphingolipid into a glycophospholipid or glycosphingolipid?

Attach a carb to the r group to sphingosine.

What is the basic structure of steroids?

3x 6-carbon rings and 1x 5-carbon ring (17 carbons in total)

`How do steroids differ?

Different 'r' groups.

How many carbon atoms are in the main chain of eicosanoids?

20 carbon atoms.

What are eicosanoids derived from?

the fatty acid arachidonic acid.

What is the main function of eicosanoids?

Communication within and between cells. Ie. Inflammation and pain

_________ are macromolecules?

Proteins are

How many amino acids are encoded by the genetic code?

20 aa

How many aa are essential? Non-essential?

9 are essential, 11 are non-essential

'R' groups are?

R groups are proteins.

What is a peptide vs. a protein?

short vs. long chain of aa

Explain the primary structure of a proteins.

It is determined by the genetic code, its an order of the aa

Explain the secondary structure of a proteins.

How the aa interact with each other, helix or folding.

Explain the Tertiary structure of a proteins.

A long change of helixes and pleats, its how the sections interact with each other.

Explain the Quaternary structure of a proteins.

Its the interaction of multiple subunits (ends up either fibrous or globular)

What is the difference between fibrous and globular proteins?

Insoluble vs. usually soluble.

What are the 7 jobs of proteins?

1. Enzymes

2. Membrane Transporters

3. Signal Molecules

4. Receptors

5. Binding Proteins

6. Regulatory Proteins

7. Immunoglobulins

In order for a protein to do anything, it must?

Interact of bind to other proteins/molecules/ions.

How is protein binding specific?

It requires a molecule that binds to a protein is called ligand

How do proteins bind with ligands?

Affinity: High = Strong, Low = Weak

What are the 2 types of ligands?

Agonist and antagonist.

What is the difference between agonist and antagonist ligands?

Alters the state of the protein and so the biological response VS. Binds without a biological response.

What are the 2 types of antagonists? Explain them.

Competitive - acts to block the agonist at its binding site

Allosteric - acts to block the agonist by binding away from the binding site (inactivates it)

Protein activity has a measurable rate which depends on? What is the max rate called?

Depends on the amount of proteins and the [ligand], SATURATION

What are the 4 factors that can alter protein binding?

1. Isoforms (closely related proteins)

2. Activation

3. Physical factors (temp, pH)

4. Modulation

What are the types of modulation?

Covalent Modification - (de)phosphorylation and the addition of a lipid or carb

Agonist/Antagonists

How does (de)phosphorylation modulate protein activity?

Enzymes called KINASES covalently add phosphates. The PHOSPHATESES remove the phosphates. Phosphorylation may cause activation or inhibition.

What are the functions of the cell membrane? - Physical Barrier

Separates intracellular fluid from extracellular fluid.

What are the functions of the cell membrane? - Gateway for control

Controls movement of solutes; allows some to cross, prevents others from crossing it (semipermeable).

What are the functions of the cell membrane? - Communication

Home to receptors that detect physical and chemical stimuli and starts a cascade of response to stimuli.

What are the functions of the cell membrane? - Cell Structure

Some membrane proteins hold cytoskeleton proteins to give cell structure, may also form specialized junctions.

What is a cell membrane made of?

Mostly proteins and lipids (different ratio for different cell types)

Models of cell membrane structure (old and new)?

Butter sandwich, now Fluid Mosaic (proteins are afloat a sea of lipids)

Lipids involved with cell membrane structure?

Glycolipids, Phospholipids, Cholesterol, Sphingolipids

Proteins involved with cell membrane structure make?

Integral, peripheral, cytoskeleton, extracellular matrix

Cell membranes have mostly what type of lipids.

Mostly phospholipids (tails inside, head outside)

Where do cholesterol molecules slip in cell membranes? What do they do?

In between fatty acid tails, to regulate membrane fluidity (slows diffusion of molecules across the membrane)

Sphingolipids are known as lipid ________.

Lipid rafts because they aggregate together which have a high density of cholesterol.

An example of proteins only associate with lipid rafts? Which does what?

G-Protein Coupled Receptors, leads to specialization