Anatomy and Physiology Exam 1

Dipolar

negative charged oxygen

positive charged hydrogen

Hydrogen bonds

Share a negative hydrogen (H)

weak bonds

provide surface tension

High Heat capacity (H bonds)

Large amount of heat before evaporation of vaporization because of bonds

Universal solvent

Negative ends of water orient towards positive ends of solute

Because of the dipole nature and solvent solution water surrounds and dissociate small cpds

Hydration layer water surrounds large proteins Re

Reactivity water

Hydrolysis water needs to go in for the reaction to break bonds

Cushioning

protection of internal organs

Amino Acid structure

Same structure but different R side chain groups

What are the two functional groups for amino acids

NH2 amine (basic group)

COOH carboxyl (organic acid group)

What can amino acids function as?

Base or an acid

what makes amino acids different?

R group

What is a peptide linkage?

chains of aa linked together make up ALL proteins

Join aa acids together (amine linked to join carboxyl end)

What type or reaction or synthesis is a peptide bond?

Dehydration synthesis (water lost)

What happens when enzymes are added?

the two aa link together

water gets added to the peptide bond and breaks

Protein primary structure 

linear sequence of aa’s (beads on a string)

\
If protein = a word

than a aa = a letter

\
A single aa can alter the structure and function of a protein

Protein Secondary structure

Twists/bends in linear aa strand

Two types of secondary structure

* a alpha helix (phone cord coils, stabilized by H bonds
* B pleated sheet ( accordion shape)

Protein Tertiary structure

Alpha helical or beta pleated sheet fold upon one another forming a ball like structure

Single polypeptide

H bonds hold them together

Quaternary Structure

Two or more polypeptide chains assembled to form larger protein molecules

H bonds hold them together

Non-polar/hydrophobic

toward inside (water repelling, hates water)

Polar/hydrophilic

Toward outside (water loving)

what are the two major classes of proteins based on appearance and shape?

Fibrous proteins (strand-like)

\- linear

\- Insoluble in water

Globular proteins (compact, spherical)

\- Water soluble

\- mobile

\- Enzymes, antibodies

What factor is most important in maintaining protein secondary structure?

Hydrogen (H) bonds

what doe enzymes activations do?

When enzyme is involved:

decrease the energy of activation for a reaction

but increases the chance for a reaction to occur

What is the enzymes function?

Binding causes shape change in the protein at the activation site

What’s the catalyst?

enzymes

What are nucleotides?

Structural components of DNA/RNA

What is the rule with large and small bases?

Purines (large bases) (Adenine and Guanine)

and

Pyrimidines (small bases) (Thymine and Cytosine)

One large and one small always

Adenine goes with what?

Thymine

Guanine goes with what?

cytosine

What replies Thymine in RNA

Uracil

What happens during DNA function?

DNA gets cocky and goes from one cell to two cells

Carries the genetic information

What happens during RNA function?

Decodes the info on DNA

Major function in protein synthesis

What does the sequence of bases contain?

genetic information

Why are proteins complex and DNA monotonous?

Proteins do everything

DNA is just a code

Where is APT made?

Phosphate group

What happens if a cell runs out of ATP

It dies

How is the phosphate bond broken?

By the hydrolysis reaction

What makes ATP to keep cell alive?

Glucose

Why study cell physiology?

cell is the basic structural and functional component of living organisms

Activity of an organism is dependent on both the individual and collective activities of its cell

Biochemical activities of cells are made possible by sub cellular structures of cells

Continuity of life has a cellular basis

what are the cells major components?

Nucleus

cytoplasm

plasma membrane

in a phospholipid what are the heads and tails?

Head - hydrophilic

tail - hydrophobic

What does cholesterol do?

adds fluidity to cell membrane

What is an integral membrane protein?

transmembrane proteins

hydrophobic and hydrophilic structure

Transports proteins

What are peripheral proteins?

inside the cytoplasmic membrane

What are the 3 types of cell junctions?

Tight junction

Desmosomes

gap junctions

What are tight junctions?

zipper like ring around cell (joins cells)

Blocks material from entering the blood

What are desmosomes?

cells under mechanical stress

located inside cytoplasmic

keratin fibers anchor plaques inside the cell

What are gap junctions?

cell - cell communication

ions pass between cells to electrical response

what is passive transport?

materials moves across the membrane without energy input

what is active transport?

Energy input ATP required to move material across the membrane

What is diffusion?

Molecules move from higher concentration to lower concentration

Move DOWN their concentration gradient

HIGH to LOW

What is simple diffusion?

Hydrophobic molecules pass through cell membrane

what is osmosis?

Movement of a solvent through a selectively permeable membrane

Water = highly polar can’t cross non polar lipid bilayer

solvent

water

Solute

Molecules in solution (salt, sugar, or other compounds)

Osmolarity

total concentration of solute in a solution

Higher osmolarity

more solute in solution

lower osmolarity

less solute in solution

Which way does the solute want to go?

high to low

What direction does water go?

high to low then equilibrium

Would a cell shrink or swell if it were submerged in a solution with a high impermeable solute concentration?

The water will come out and the cell will shrink since the water is leaving

Tonicity

ability of solution to change

Solutions with non penetrating solutes

solutes cannot cross cell membrane

isotonic solutions

Equal concentration inside of cell (will not change shape)

Hypertonic solutions

Higher concentration os solute that inside of cell

cell shrinks (water leaves cell)

Hypotonic solution

low concentration of solute than inside cell (cell will swell, water moves into cell)

Which of the following molecules would pass through the lipid bilayer of the cell membrane without requiring a transporter or channel protein?

Steroid

Which region in the cell membrane is considered hydrophobic?

Central region consisting of two nonpolar fatty acid tails of the \n phospholipid molecules. One phospholipid from directed outside the cell and one phospholipid directed from the inside to the cell.

Contact signaling

Cell - cell contact

this helps provide immunity

and is important for development

Electrical signaling

Excitable cells

neurons and muscle cells

causes receptors/channels to open up and close

Chemical signaling

Compounds bind to cell membrane receptors and change cellular function

(compounds sit outside cell and change how the cell works)

Ligand:

\- Hormones → From distant cells

\- Paracrines → from local cells

what does the response in cellular machinery depend on?

type of receptor

Type of response depends on type of receptor

What are the steps of chemical signaling

1. Ligand binds to receptor
2. Ligand/receptor complex changes (structure of receptor)
3. Results in change in cellular proteins

What are G proteins?

Ubiquitous proteins (found in many cells)

many receptors are linked to them

What do G proteins activate/inactive?

Generates a second messenger in cell which functions inside the cell

What are the types of second messenger?

cAMP

Calcium

Nitric oxide

What happens during cAMP

1. Hormone in blood calls for the first messanger (outside of cell)
2. The first messenger binds to the receptor and when they come together it changes shape
3. This activates the G protein
4. The G protein the activates the enzyme
5. When activated the second messenger comes along and is inactive and becomes active
6. Then cAMP goes up

Amplification

Enzymes activate more enzymes on top of more enzymes

Produces second messenger

What happens during Nitric Oxide?

a small gas inside and outside of the cell

Since small it diffuses outside of cell and effects other cells

Where is the cytoplasm located?

Outside of nucleus

Where is the cytosol located?

outside cytoplasm

What are orgnaelles?

They’re surrounded by membrane

Important for cell function

All second messengers function execluisvley within the cell

False (nitric oxide can diffuse outside of the cell and function outside the cell)

what do Peroxisomes do?

Self replicate

Contains oxidase enzymes that protect us (detoxify)

Free radicals damage a lot of stuff

What do free radical do?

Damage proteins lipids and DNA

Superoxide is a highly reactive product

stress and working out too hard produce more free radicals

What do peroxisome do

convert free radicals to peroxide (H2O2)

What is the function of ribosomes?

Protein synthesis

What are the two types of ribosomes?

Free floating - float around freely

Attach to the ER

What does the ER do?

it is fluid filled cavities

There are rough ERs and smooth ERs

what do Rough ERs do?

Synthesize all secreted proteins

Synthesize membrane components

goes to Golgi for more processing

What does the smooth ER do?

breaks down fat

Complex network of tubes in cardiac and skeletal sarcoplasmic reticulum

muscle contraction

What does the Golgi apparatus do

Traffic director of cellular proteins

What happens inside the Golf

Proteins inside are modified (matured inside it)

The proteins are then tagged and ready for shipping and go through 3 different phases

What are the 3 phases for the protein after maturing in the golgi

1. Secondary vesicles - release proteins outside cell
2. Vesicles with proteins are locked outside membrane
3. Vesicles with hydrolytic enzymes remain in cytoplasm as lysosomes

what are Lysosomes functions?

1. Digest material entering cell by endocytosis
2. break down glycogen
3. Degrade nonfunctioning tissues

what is a specific enzyme?

degrade a neuronal membrane glycolipid

mRNA

carries DNA code for polypeptide chains

tRNA

corrects aa for each base triplet (codon)

rRNA

assosiated with ribosomes

Proteasomes

Large complexes of proteins degrading enzymes

Breaks sown old and used up damaged proteins

Ubiquitin

attaches or tags old proteins and that tells the proteomes to throw them away