Biol 319 exam 3 (Lee)

Joint diseases (3)

Rheumatoid arthritis- long term autoimmune disorder affecting joints, warm swollen and painful wrists

Osteoarthritis- progressive thinning of hyaline cartilage, bone spurs on heel!!

Gout arthritis- deposition of needle like crystals of uric acid in the joints

Types of bone fractures

Compound: bone penetrates skin

Comminuted: bone is in pieces

Transverse: perpendicular with medullary cavity

Linear: parallel with medullary cavity

Oblique: at an angle

Green stick: small break, bone bends before it breaks

Spiral: twists wrong

Dendritic cells

Most often found in high numbers within tumors

Antigen preventing cells that "sound the alarm" and ramp up the immune response by presenting antigens that are foreign

What is an autoimmune disorder

A disease in which the body's immune system attacks healthy cells.

An antibody or ig (immunoglobulin) designed to attack foreign properties but they attack our proteins

Fascia

a band or sheet of fibrous connective tissue that covers, supports, and separates muscle

"Sarcos" and "Myo"

Sarcos- flesh

Myo- muscle

Types of skeletal muscle fibers

Type 1- slow oxidative (marathon runners)

Type 2A- fast oxidative

Type 2B- fast glycolytic (sprinters)

FLAT PEG

Hormones that come from the anterior pituitary

FSH- follicle stimulating hormone

LH- luteinizing hormone

ACTH- adrenocorticotropic hormone

TSH- thyroid stimulating hormone

Prolactin- functions to produce milk

Endorphins

GH- growth hormone

Osteophyte

bony outgrowth

Mostly a bone spur of the heel

Anterior and posterior pituitary

ADH (vasopressin) and oxytocin (made in hypothalamus) are released in the posterior pituitary

What is vasopressin and what does it do

vasopressin (antidiuretic hormone, ADH)

- hormone against urine formation

- caffeine and C2H5OH (alcohol) inhibit ADH so urine production will go up

- ADH goes up and urine goes down

Gout (kidney) 🙏🙏🙏🙏

Deposition of needle like crystals of uric acid into joints

Under secretion of uric acid by the kidney causes this

Interferons 🙏🙏

Muscular dystrophy

Dystrophy: a group of more than 30 genetic diseases that cause progressive weakness and degeneration of skeletal muscles used during voluntary movement

This disease causes: muscle degeneration, fiber death, fiber branching and splitting, phagocytosis, chronic or permanent shortening of tendons and muscles

Myopathy & neuropathy

Myopathy: disease of muscle in which the muscle fibers do not function properly, results in muscle weakness. Primary defect is in muscles

Neuropathy: affects the peripheral nerves

What is the most prevalent amino acid in higher vertebrates?

glutamate

- binds to taste bud receptors and we taste "savory"

(Umami)

All functions of skeletal muscle

-Movement: produces tension (pulling or squeezing) to move things

-posture: baseline tension

-joint stability: constant tension holds joints together

-thermogenesis: muscle creats heat in act of shivering

-nutrition: muscle can be broken down for nutrients if a person is experiencing starvation

Hemodynamics formulas (3)

Cardiac output= stroke volume X heart rate

Delta P= Q(flow) X R(resistance)

MAP (mean arterial pressure) = D + (S-D)/3

Stand up too quickly

Become lightheaded, BP goes down, Baroreceptors pick up on change in pressure and signal to the medulla obligate to vasoconstriction and heart rate increases

Locked knees while standing

Leg muscles aren't being continually flexed, inadequate blood flow to the brain, BP goes down and you become lightheaded

Location of major Baroreceptors

Aortic arch, carotid sinus

Creatine

First energy source used is creatine

- creatine shuttles into muscle and water follows causing muscle to swell

If you take alot of creatine it swells your muscles but when you stop taking it it causes your muscles to shrink

Creatine kinase

Kinase adds phosphate to creatine. When it has phosphate it can give the phosphate to ADP which regenerates ATP

Myoblast

Makes or builds muscle

Whole muscle, fascicle .......

Whole muscle > fascicle > muscle fiber (myocyte, myofiber) > myofibril > myofilament

Microscopic muscle during muscle contraction. What shortens?

Shorten: The sarcomere, H band, I band

Don't shorten: A band, actin, myosin

4 steps of muscle contractile cycle

1. When AP hits the sarcoplasmic reticulum, Ca++ is released and the Ca will bind to troponin. This moves the tropomyosin out of the way exposing the myosin head binding sites on the actin filaments. When the myosin binds it is called the cross bridge formation

2. Myosin heads will "pull" actin over the top of the myosin (when they release the ADP and Po4 group on them). This is called the power stroke sliding filament theory.

3. A new ATP binds to the myosin. This causes the myosin head to detach from actin.

- if out of ATP- CRAMPS vs rigor mortis

4. Myosin can not only bind ATP but can hydrolyze it to ADP and Po4 which "recocks" the myosin head so it is ready to be attached to another

RMP

resting membrane potential

Charge inside cell is more negative than the positive outside

All tissues have RMP but only muscle and nervous use this to form AP

AP

Action potential

A wave of depolarization along or down a membrane

No bigger or smaller AP- you can have fewer or more depending on the muscle being used

All integral proteins involved with AP and RMP

Chlorine, potassium, calcium, sodium

ATP hydrolysis

Turn a positive delta G into a negative delta G

Against the gradient- can make something that doesn't want to happen happen (Na going out, K going in)

AP GRAPHS🙏

AP starting and ending

AP starts when we get to threshold (-50)

AP ends when we get back to resting value (70)

Depolarization

Na in -> starts making cell more positive

VG Na channel will open at the threshold and close at +35

Repolarization

K out -> starts making cell more negative

VG K channel will open at +35, starts to close around resting but will actually close at about -90

Hyperpolarization

Goes below resting and it's more negative than RMP

Further away from threshold- tissue will be less active or no activity at all

If it's very hyperpolarized then there is no change to get back to threshold

Actin, myosin ATPase, troponin, tropomyosin

Actin: thin myofilament

Myosin: thick myofilament - binds ATP and hydrolyzes ATP

Troponin: binds calcium

Tropomyosin: blocks the myosin head binding sites (until troponin binds with Ca)

Steps of contractile cycle

1. Binding of myosin head to a myosin binding site on actin (cross-bridge formation). At this stage, myosin has ADP and Pi bound.

2. Power stroke: myosin head moves into a low energy conformation and pulls the actin chain toward the center of the sarcomere (ADP is released).

3. Binding of new ATP molecule is necessary for release of the actin by the myosin head.

4. ATP hydrolysis occurs immediately and the myosin head is cocked (high energy conformation)

AP and which ions moving in which direction

AP involves Na and K

Na out

K in

Ligand

The molecule that binds to a receptor

Ligand gated receptor/ channel- the channel will be ion specific

Summation

The waves of EPSP and IPSP that lead to the threshold

Made up of ligand gates receptors that will turn into channels at threshold

Histone

What DNA wraps around

Found in groups of 8 (octets)

Kinase

An enzyme that adds a phosphate group

- the phosphate is responsible for turning the pathways off

How many jugular veins do humans have?

6 jugular veins (3 pairs)

IPSP and EPSP

EPSP- excitatory post synaptic potential: getting closer/ moving towards the threshold

IPSP- inhibitory post synaptic potential: getting further/ moving away from threshold

Voltage gated channels

Amino acid residues that are associated with a protein

Can open or close (can have one or two gates)

muscarinic receptors

Muscarinic: IPSP

- goes away from threshold

- chlorine (anion) goes in, potassium (cation) goes in

- pacemaker for the SA node of the heart

Nicotinic receptors

Nicotinic: EPSP

- sodium goes in

- moves to threshold

- found in skeletal muscle

- ACH binds to this

4 integral proteins and what is an integral protein?

channels, carriers, pumps, receptors

Proteins imbedded within the cell membrane

Why does the Na-K-ATP pump require ATP to function?

Because the process goes against the concentration to restore Na+ and K+ to original resting potential amounts

Low to high concentration

AP rolls like a wave, what does that mean?

Depolarization looks like a wave.. down the cell membrane

What is a second messenger?

a substance whose release within a cell is promoted by a hormone and that brings about a response by the cell.

cAMP

cGMP

IP3

DAG

NO

Ca++

Vagus nerve effect on the SA node

Decreases heart rate by releasing acetylcholine

Muscle soreness

overexertion in strenuous exercise resulting in muscular pain

Immediate: muscle burns during act of muscle contraction

24-48 hrs after: leads to tiny micro tears in the muscle

Weeks: extreme over exertion, the body has not adjusted

Satellite stem cell recruitment

24-48 hours after heavy lifting or over exertion, leads to tiny micro tears in the muscle

Needs to be repaired (testosterone levels go up) testosterone turns on genes for muscle repair = true muscle building

Corticosteroid injection when a tissue is wounded

Cortisone shot into the joints- trying to get pressure, pain and inflammation down

Inhibits HAT, promotes HDAC

- HAT= histone acetate transferases- add Ac

- HDAC= histone deacetylases- remove or don't put on Ac