ES207 EXAM 2

1. Excess growth hormone results in: Giantism

2. Proteins, peptides, and amino acids are: Water-soluble hormones

3. Gonadotropin releasing hormone does what? Stimulates release of FSH and LH from ANTERIOR pituitary

3. Alpha cells secrete: Glucagon

4. Lamellar bone is: Mature bone

5. Which joint is least moveable? fibrous

6. When you're done growing what happens to epiphyseal plate? becomes a line

7. Put these in order from smallest to largest: filament, fibril, fiber, fasicle, muscle

8. What is covering the myosin heads? Tropomyosin

9. What muscle fibers are gonna be mostly used during long distance running? Slow twitch

10. T tubules carry what into the sarcomere? Action potentials

11. An injury to a tendon is a injury to a ligament is: Strain and sprain

12. Concentric and eccentric contractions are types of: Isotonic contractions

13. Calcitonin is a hormone produced by the thyroid gland. What is its primary function in the human body? Lowers blood calcium levels by inhibiting osteoclast activity

14. Which of the following correctly describes the sequence of events during the depolarization phase of an action potential? Sodium (Na+) channels open, sodium enters the cell, and the cell membrane potential becomes less negative

15. Which of the following correctly describes the sequence of events during the repolarization phase of an action potential? Potassium (K*) channels open, potassium exits the cell, and the membrane potential becomes more negative.

16. Which of the following best describes how hormones interact with target tissues?Hormones only interact with tissues that have specific receptors for that hormone.

17. How does hormonal amplification work in the context of endocrine signaling? A single hormone molecule binds to multiple receptors on target cells, resulting in a large number of secondary messengers.

18. Which of the following best describes the role of calcium ions (Ca2+) in muscle contraction, and what would be the effect on a patient if they were unable to release calcium from the sarcoplasmic reticulum? Calcium ions bind to troponin, causing a conformational change that allows actin and myosin to interact. Without calcium release, the muscle cannot contract and would remain in a relaxed state.

19. What would happen to muscle contraction if ATP were unavailable and cross-bridge formation occurred? The muscle would contract normally, but relaxation would be impaired, causing sustained muscle contraction (rigor).

20. During muscle contraction, which of the following accurately describes the interaction between myosin and actin, and what occurs as a result? Myosin filaments move along the actin filaments, and the myosin head attaches to the actin, pulling it toward the center of the sarcomere, causing the muscle to contract.

ENDOCRINNEEEE
• Endocrine glands secrete hormones directly
into the bloodstream
• Hormones circulate in the blood until they
reach the target tissue and produce a specific
response
• Chemical Messenger Classes:
• Neurotransmitters secreted by nerve cells
• Hormones secreted into blood and bind to receptors
• Functions: Can you name some?!

Classes of Hormones
Water-Soluble
• Proteins, peptides, amino acids
• Most common type
• What are some examples?
Lipid-Soluble
• Steroids, eicosanoids
• What are some examples?

Secretion of Hormones

Humoral

•Chemicals in the blood stimulate release of hormones

•Example: blood calcium stimulating endocrine cells to secrete (or not secrete) PTH

Hormonal

•Hormones stimulating the release of other hormones

•Example: Gonadotropin Releasing hormone (GnRH) stimulating the anterior pituitary gland to release LH and FSH

Neural

•Neurons release neurotransmitter into synapse of cell that produces the hormone

•Example: Neuron releasing ACh to stimulate the adrenal medulla to release epinephrine

Humoral vs Hormonal vs Neural

if Ca2+ levels too low in blood → PTH is secreted → osteoclast formation → increased blood Ca2+

if Ca2+ levels too high in blood → PTH is NOT secreted → osteoclast doesnt form → decreased blood Ca2+

Types of Receptors
HORMONES CAN ONLY STIMULATE THE CELLS THAT HAVE
THEIR SPECIFIC RECEPTOR
Membrane Bound Receptor
• Located on the plasma membrane of a cell
• Acts in two ways:
1) Activation of G proteins  production of second messengers
2) Directly altering activity of intracellular enzymes
• What type of hormone would this be associated with?
Nucleus Bound Receptor
• Located on the nucleus
• Hormone must diffuse through plasma membrane to bind to receptor
• What type of hormone would this be associated with?

Resistance train to combat  osteoporosis - no menstruation not enough estrogen, intense athletic can increase likelihood 

Sarcomere = smallest contractile unit of muscle 

Anterior:
o Growth hormone (GH)
o Adrenocorticotropic (ACTH)
o Thyroid-stimulating (TSH)
o Gonadotropic (FSH, LH)
o Melanocyte-stimulating
o Prolactin

• Posterior:
o Oxytocin
o Antidiuretic (ADH)

Even More Hormones
• Calcitonin: reduces blood calcium levels when high (think osteoblasts!)
• PTH: stimulate osteoclasts if blood Ca is too low, stimulates Ca lost in urine when
blood Ca is too high
• Adrenal Medulla: Epi/NorEpi: released from flight or flight response
• Adrenal Cortex:
• Aldosterone: regulate ion balance, retention of Na & water and, secretion of K
• Cortisol: increase breakdown of fat or protein for energy
• Androgens: secondary male sex characteristics, female sex drive
• Pancreas: alpha cells=glucagon; beta cells=insulin; delta cells=somatostatin, all of
these work to regulate blood glucose levels

The Skeletal
System
Functions:
1. Body support
2. Protect organs
3. Body movement
4. Mineral storage (Ca, P)
5. Blood cell production
(hematopoiesis)

Synovial
• Freely moveable
• Joined by fluid filled cavity
• Most joints involved in appendicular skeleton
• Functional classification = diarthrosis
• Cartilaginous
• Somewhat moveable
• Connected by cartilage
• Functional classification = amphiarthroses
• Fibrous
• Completely immovable
• Connected by fibrous connective tissue
• Functional classification = synarthrosis

know what/where: pivot, saddle, plane, hinge, condyloid, and ball/socket joints

Additional Bone Stuff
• What is the function of parathyroid hormone within bone
formation?
• What is the function of calcitonin within bone formation?
*WHAT IS WOLFF’S LAW

Muscular System
• Functions: movement, posture, respiration, body heat,
communication, constriction, contraction
• Contractility- ability to shorten forcefully
• Excitability- the capacity to respond to stimulus
• Extensibility- ability to be stretched beyond normal length
• Elasticity- ability to return to normal length
• Small to large: myofilament, myofibril, muscle fiber, muscle
fascicle, whole muscle
• Epimysium=outer, perimysium=middle, endomysium=inner

Muscle Contraction
• Steps of depolarization:
• THESE ARE GUARANTEED TO BE ON THE EXAM
1. At RMP, voltage-gated channels are closed
2. Na+ enters from adjacent region causing voltage gated Na+ channels to open
3. Na+ enters axon causing the membrane to have a positive potential
4.Na+ channels close becoming inactive for a period of time
• Steps of repolarization:
• AGAIN, GUARANTEED TO BE ON THE EXAM
5. depolarization opens K+ channels causing K+ to diffuse out. this causes a negative
membrane potential
6.hyper polarization occurs since K+ channels remain open. (what this means is K+
channels stay open longer than they need to in order to overshoot the RMP)
7.K+ channels close and RMP is reestablished

Additional Muscle
Info- Isometric contractions: increase tension, no change in length
- Isotonic contractions: increase tension, decrease length
o Concentric: muscle ______
o Eccentric: muscle _____
- Summation= force in single muscle fiber
- Recruitment- force of whole muscle
- Motor unit: a single motor neuron and all the muscle fibers it
innervates (When are small and large motor units useful?)
- Muscle fiber types: Slow, Fast, Slow Glycolytic (differences?)
- Action: what is it?
- Inhibition: what is it? Why is it useful in clinical care?
Types of muscle
- Skeletal muscle: voluntary, striated, most common
- Cardiac muscle: in the heart, uninucleated, connected with
intercalated disks, involuntary
- Smooth muscle: lines organs, involuntary, smooth, uninucleated

Additional Muscle
Info- Isometric contractions: increase tension, no change in length
- Isotonic contractions: increase tension, decrease length
o Concentric: muscle ______
o Eccentric: muscle _____
- Summation= force in single muscle fiber
- Recruitment- force of whole muscle
- Motor unit: a single motor neuron and all the muscle fibers it
innervates (When are small and large motor units useful?)
- Muscle fiber types: Slow, Fast, Slow Glycolytic (differences?)
- Action: what is it?
- Inhibition: what is it? Why is it useful in clinical care?
Types of muscle
- Skeletal muscle: voluntary, striated, most common
- Cardiac muscle: in the heart, uninucleated, connected with
intercalated disks, involuntary
- Smooth muscle: lines organs, involuntary, smooth, uninucleated