BIO110: PHYSIOLOGY QUIZ 2 GUIDE

DEFINE TENDON

muscle to bone

define ligament

attaches bone to bone

define motor unit

One motor neuron plus all of the muscle fibers it innervates

define thick filament

• aka myosin

• attaches to actin using the “myosin head”, ATP + P attaches onto the head to begin the attachment. Once attached the ATP + P is released and slides the actin to the center of the sacromere

define thin filament

• aka ACTIN

• Allows the myosin to attach onto actin to allows the actin to slide into the center of the sarcomere

define sacromere & draw the diagram

• the smallest functional unit of skeletal muscles

define origin and insertion of muscles

• Origin: part of the muscle that does not move joint

• Insertion: part of muscle that does move joint

define creatine kinase

• Creatine Kinase is the enzyme that catalyzes creatine phosphate + ADP to make ATP. It is reversible as well

• First source of energy for skeletal muscle

what is the function of T-tubules

• AKA transverse tubules: carry electrical signals deep into the muscle fibers. Triggers the sarcoplasmic reticulum to release calcium, the calcium allows the muscle to contracts

• Bring action potential inside the cell

what is the function of myoglobin

• Stores oxygen in the muscle

• Hemoglobin stores o2 into the rbc

where is calcium stored in muscle cells and how is it released during contracton?

• Stores: sarcoplasm reticulum

• released: action potential created by acetylcholine

what is the cross-bridge cycle

• Actin attaches to myosin and contracts the muscle

what happens to the sacromere during contraction?

• What specifically changes 

  • Z lines move closer together 

  • I band gets smaller 

  • H zone gets smaller or disappears 

  • A band stays the same length 

• Why this happens 

• Actin (thin filaments) slide over myosin (thick filaments).
  The sarcomere gets short / small

what is the difference between fast and slow muscle fibers?

• fast / slow myosin ATPase

  • Fast fibers contain fast ATPase. It splits ATP rapidly, allowing cross bridge repeat quickly, it is faster but tire easily

  • Slow fibers contain slow ATPase. It splits the ATP slowly, allowing the cross bridge to repeat slowly. It is slower but lasts longer

When oxidative phosphorylation is not sufficient, what becomes the source of energy and what is the byproduct?

• Phosphorylation of ADP by creatine phosphate 

• Oxidative phosphorylation of ADP in mitochondria 

• Anaerobic glycolysis

What type of neuron causes skeletal muscle contraction

motor neuron / alpha motor

define polycythemia

increased erythrocytes

define hypoxia

low oxygen in the tissue

define hypoxemia

low oxygen in arterial blood

define anemia

A reduction of amount of oxygen/hemoglobin a red blood cell can carry or lack of production in RBC

• Decrease oxygen carrying capacity

define hematocrit

The fractional amount of erythrocytes to the blood is called the hematocrit

define hemoglobin

a protein in red blood cells that carries oxygen and carbon dioxide

define albumin

where is albumin produced in

• Albumin is the most abundant protein in blood plasma.

• Maintains osmotic pressure → helps keep fluid in blood vessels

  • keeps water into veins/B.V. away from tissue

• made from liver

define EPO

Erythropoietin

hormone released from the kidney in response to low oxygen; stimulates the synthesis of erythrocytes

What is/are endothelium and endothelial cells

where can you find them?

• Endothelial cells: The individual cells that make up the inner lining of blood vessels and the heart.

• Endothelium: The layer formed by endothelial cells. It is the continuous lining inside blood vessels and the heart.

lining blood vessels of the heart

define nitric oxide

• Produced at: endothelium

• Function: dilates blood vessels and prevent platelet aggregation / clumping

• Stops clot formation

define hemostasis

stop blood loss

what is the life cycle and lifespan of red blood cells

• Lives 120 days

• Cycle: 

  • kidney sends EPI > bone marrow to produce red blood cell 

  • When young, RBC is flexible. When old, it gets hard and brittle > spleen (which is narrow) = young will thrive but old will be brittle and break into parts. In the spleen RBC will break into Globin + heme into bilirubin + iron

  • Bilirubin > liver & turn into bile

    • Bile > kidney > urine

    • Bile > digestive > poop

what substance gives urine and feces their yellow colour?

biliburin

what are the function of the spleen?

Removes waste and damaged RBC

what is fibrinogen and what role does it play in clot formation?

Fibrinogen is synthesized by the liver and is a key substance in the formation of blood clots.

what converts fibrinogen into fibrin?

thrombin

what is hematocrit and what is the normal range?

• What is hematocrit and what is the normal range?

  • percentage of RBC present in Total Blood volume

  • Men: 42-52%

  • Women 37-47%

  • around 45%

which organ produces the most clotting factors?

liver

what are the function of hemoglobin?

protein in the RBC that Produces oxygen and carbon dioxide

what is pernicious anemia

condition is due to a lack of vitamin B12

What is jaundice and which substance causes it when elevated?

Yellowing of eyes and skin due to increased bilirubin

define cardiac output?

• Cardiac output is the amount of blood the heart pumps per minute.

• CO = SV × HR

define stroke volume and what is normal range?

• Stroke volume is the amount of blood ejected by the left ventricle of the heart in one heartbeat.

70ml

define mean arterial pressure

Mean arterial pressure (MAP) is the driving force for blood flow through the systemic circulation.

• MAP = 1SBP + 2 DBP / 3 

• AVERAGE IS 90

define TPR

TOTAL PERIPHERAL RESISTANCE

• in the systemic circuit (blood flow L heart > body > R heart), the combined resistance (resistance determines how hard the heart must pump) of all the blood vessels

• Example: Narrower or more numerous pipes → higher resistance, All the pipes together = total resistance in the system

TPR=MAP/CO

DEFINE EJECTION FRACTION

• Ejection fraction is the percentage of blood pumped out of the ventricle with each heartbeat.

• EF = STROKE VOLUME / END-DIASTOLIC VOLUME * 100

  • SV: BLOOD EJECTED PER BEAT

  • EDV: BLOOD IN VENTRICLE BEFORE CONTRACTION

  • Normal: ~55-70% (54%)

DEFINE COMPLIANCE

• ability for b.v. to stretch

  • arteries = low compliance

  • veins = increased compliance

define PP

“pulse pressure”

• PP = SYSTOLIC PRESSURE - DIASTOLIC PRESSURE

define ischemia

decreased blood flow to a tissue / organ

define arterial baroreceptors

pressure receptors in the artery that senses presusre change in the blood

define role does MAP play in systemic circulation?

Mean arterial pressure (MAP) is the driving force for blood flow through the systemic circulation.

• MAP = 1SBP + 2 DBP / 3 

• AVERAGE IS 90

what is the driving force of blood in a closed system

MAP

what is the compliance of arteries versus veins

• Compliance is how easily a blood vessel can stretch when pressure increases.

• Arteries

  • Stiffer (low compliance)

  • Can maintain high pressure

• Veins 

  • Stretchy (high compliance)

  • Can store large volumes of blood

what is total peripheral resistance and how is it calculated

• in the systemic circuit (blood flow L heart > body > R heart), the combined resistance (resistance determines how hard the heart must pump) of all the blood vessels

• TPR = MAP / CO

in which type of vessels does the largest drop in arterial pressure occur

arterioles because they provide the greatest resistance to blood flow.

which vessels have the greatest total cross-sectional area

Capillaries have the greatest total cross-sectional area, allowing slow blood flow for exchange with tissues.

which artery is most commonly used to measure blood pressure

• Blood pressure is most commonly measured in the brachial artery of the upper arm.

at rest where is most of the blood in circulatory system found and why?

• At rest, most blood is in the veins (60%) because they are compliant and serve as blood reservoirs.

is atrial fibrillation usually fatal?

• Atrial fibrillation is usually not fatal on its own, but it increases the risk of stroke and heart failure. Often managed with medications (rate/rhythm control, anticoagulants)

What is the myogenic response?

IF BLOOD VESSELS STRETCH, IT RECOILS

define diffusion, filtration, and reabsorption in capillaries

• Capillaries are thin-walled vessels where substances move between blood and tissues. There are three main mechanisms:
  

  • Diffusion Definition:  Movement of molecules from high concentration → low concentration.

  • Filtration Definition: Movement of fluid from blood to interstitial

  • Reabsorption Definition: Definition: “Movement of fluid from interstitial to blood”

what are the different types of capillaries

• Continuous capillaries: 

  • Most common type

  • Small gaps between endothelial cells; allow for watersoluble substances; if larger than water-soluble molecules, it is more difficult to  pass through

• Fenestrated capillaries

  • Large gaps between endothelial cells forming pores or fenestrations (windows)

  • Allow proteins, and in some cases blood cells, to move through

define the function of veins

• large blood vessels that carry blood toward the heart

• called "volume reservoir”

  • blood remain in veins and moves only by the muscle of the veins

  • keeps 60% of blood

define active vs reactive hyperemia

• Active: increased blood flow in response to increased metabolic activity

• Steady state:

  • O2 is delivered as fast as it is consumed 

  • CO2 is removed as fast as it is produced

• Increased metabolic rate

  • O2 is consumed faster than it is delivered 

  • CO2 is produced faster than it is removed

• Reactive:  increased blood flow in response to a previous reduction in blood flow

  • Blockage of blood flow to tissues

    • Metabolites increase and oxygen decreases

    • Vasodilation

  • When blockage is released

    • ncreased blood flow due to low resistance

    • Metabolites removed, oxygen delivered

define effect nitric oxide has on blood vessels

• causes vasodilation by relaxing vascular smooth muscle

• stops clot formation

define general function of adrenergic receptors

• Alpha:

  • 1) Blood Vessels 

  • 2) CNS

• Beta:

  • 1) heart

  • 2) lungs

  • 3) adipose

• The general function of cholinergic receptors

  • Muscarinic:

    • All organs

  • Nicotinic 

    • Neuromuscular junction

which adrenergic receptor are found mosly in blood vessels

alpha 1

what are arterial baroreceptors

pressure receptors that senses pressure changes in BP

which of the central nervous system controls the cardiovascular centers?

The brainstem controls the cardiovascular centers specifically the medulla oblongata acting to regulate the HR and BP. 

what is filtration and reabsorption

Filtration: Movement of fluid/solutes across a membrane due to pressure.

• example: fluid from the blood stream enters the tubules of the kidneys
  

Reabsorption: refers to movement of filtered solutes and water from the lumen of the tubules back into the plasma.

what is the function of endothelium

Endothelium: The layer formed by endothelial cells. It is the continuous lining inside blood vessels and the heart. Think of it as the “tissue,” while endothelial cells are the “building blocks.

what is the role of EPO in oxygen regulation

• EPO = erythropoietin

• Erythropoietin is released from certain cells in the kidney in response to low oxygen levels in blood. 

bands of sarcomere

• A Band: measures the length of thick filaments, contains thick & thin filaments

• H zone: part of the A-band, contains ONLY thick filaments

• I band: contains only thin filaments

• M band: links thick filaments together

• Z line: links thin filaments

what are the 3 sources of ATP?

1. creatine phosphate

   1. aka “energy on tap” does not depend on body state or food. DEPENDS NO FACTORS

   2. on set / right away

   3. does not last long (30 seconds - 60 seconds)

2. Oxidative phosphorylation

   • Burns food to make ATP

   • Reliant on body state and food

   • The primary source

   • Limited by oxygen

3. anaerobic glycolysis

   1. becomes dominant source when oxygen is low

   2. break down glucose without affecting o2

   3. problem: produces lactic acid