3B

Circulatory.immunity, nephron

What happens during sarcomere contraction? What happens to the length of thin and thick filaments? What about their distance to one another?

Filaments will not change length but will overlap each other more

actin- thin

myosin: thick

What is a motor unit pool?

Number of motor units that a muscle can recruit for contraction

The size of a motor unit pool is ____ related wit muscle contraction

Directly

As muscle cells contract, motor units will increase the amount of Calcium _____. When relaxing, muscle cells ____ Ca.

Released, reuptake

What are the components of plasma (4)

Proteins, nutrients, salts and hormones

What are the proteins within plasma (3)? What are their functions?

1. Albumin: Major osmo regulatory protein (maintains fluid/stay hydrated

2. Fibrinogen: Clots our blood

3. Immunoglobulins: OUR ANTIBODIES, made by B cells!

What do RBC/erythrocytes lack?

Nuclei and membrane bound organelles?

Do RBCs have mitochondria? Why or why not?

They DO NOT have mitochondria because they would utilize the O2 they need for themselves!

How many subunits does myoglobin have? What does that effect?

It has ONE which, INCREASEES oxygen affinity

This means that myoglobin get saturated MORE QUICKLY than hemoglobin!

Myoglobin has a ___ curve due to ____while hemoglobin has a ____ curve due to ___.

Hyperbolic: Having one subunit

Sigmoidal: Cooperative binding

From what kind of cells do lymphoid and myeloid stem cells come from?

hematopoietic stem cells

What are the stem cell origins of the innate and adaptive immune system respectively?

Myeloid, lymphoid stem cells

What are the two main components of INNATE immunity? What are the components of each? What are the ways of action for the components found in #2? Basically fill in the chart and take note of actions within them.

Granulocytes

Basophils: Mediate allergic responses

Eosinophils: Mediate allergic responses and respond to parasitic infections

Neutrophils: Ingest bacteria, particularly those marked with antibody

Monocytes

Macrophages: Ingests deadcellls, phagocytoses pathogen and displays antigen

Dendritic Cells: Phagocytoses pathogen and displays antigen on MHC-II

NK Cells: Attack cells not presenting MHC molecules Self MHC-I

What is the difference between active and passive antibodies?

Active: Trained B cells create the antibody

Passive: Made by somebody else like mother’s milk or the placenta

Why does a second exposure to virus have a much quicker immune response?

At that point B cells have been trained (specific antibody)and have proliferated and are recruited by helper T cells

What is hemolysis?

When blood cells rupture because blood has foreign antigens that antibodies can’t recognize

Antigens in blood are directly related to their _____. What are the antigens for each?

A: A antigens

B:B antigens

AB: Both antigens

O : No antigens

Antibodies in blood will be made against ____. Can you give examples?

Since A presents A antigens, there are no B antigens so they produce B antibodies (Way to recognize a foreign blood antigens like B)

Meanwhile AB would not have any antibodies since they recognize A and B antigens! That’s why it can only be donated to another with AB blood because we have to make sure there are no antibodies against like in B blood there is a A antibody which would go against the A antigens in AB but they can recieve from all blood types!

O blood type would have A and B antibodies since there are no antigens! With no antigens, they are a UNIVERSAL donor. But they can only recieve blood from O type.

What kind of antibodies are in co dominate blood type? What about Rh factor?

IgM, IgG

What kind of inheritance is Rh factor? How do we distinct antigens? Explain issues with this blood type in mother and newly born child?

Dominant inheritance

Positive or negative, negative meaning no antigens.

You only make antibodies when exposed to a foreign Rh antigens (mixing of blood)

So if mom has B- and their baby is B+ the 1st baby is safe if they mix blood during a procedure but if the mother has a second child with B+ the infant will die due to hemolysis

Increasing the influx of interstitial fluid into the blood stream would ____ blood pressure

Increase

Fill out the table!

A higher osmolarity means that the fluid _____.

Has more solutes in it!

Label the names of each structure, their step, relative osmolarities

The higher the concentration of glucose in the plasma, the __ the rate of filtration into the nephron. How does this relate to reabsorption and excretion?

1. Higher

2. Although reabsorption will increase eventually there will not be enough transporters (transport maximum), then at that point there will be an increase in glucose excretion otherwise known as more sugar in URINE

How does the osmotic and hydrostatic pressure of the glomerular capillary and Bowmans space compare?

Hydrostatic pressure of the capillary is much greater due to the amount of blood coming in, and the oncotic pressure is higher because albumin is too big to filter into the nephron

The hydrostatic pressure of the Bowman capsule on the other hand is much lower. Oncotic pressure is also lower due to less albumin being filtered through.

What contributes to the net flow of fluid into the nephron

The higher hydrostatic pressure from the glomerular capillary!

What happens and why?

Decreases in hydrostatic pressure so less fluid will make it to the glomerulus to be filtered

What happens here and why?

Back flow in glomerular capillary increases which increases ist hydrostatic pressure

What if there was a kidney stone?

Back up of fluid in the nephron resulting in increasing hydrostatic pressure of the Bowman space, decreasing filtration

Aldosterone versus vasporessin/ADH(antidiuretic hormone). What regulation do they MOSTLY do?

Aldosterone:Reabsorption water and ION

Regulation: Plasma volume AND pressure

Vasopressin: Reabsorption of water ONLY

Regulation: Plasma osmolarity

The loop of Henley is ____ likely to be longer than the collecting duct

More

How do cytotoxic (CD8⁺) T cells kill infected cells?

🧠 Step 1: Recognize infected cell via MHC I + foreign antigen

🔫 Step 2: Kill via

• Perforin + Granzymes → poke & trigger apoptosis

• Fas-FasL interaction → activate cell's death pathway

➡ Result: Target cell undergoes apoptosis, not messy lysis
✅ Keeps infection from spreading without harming nearby cells

What is the difference between the MHC complexes?

💍 Engagement Proposal Analogy:

MHC Type	Analogy	Who Sees It	What Happens
MHC-I	Private proposal: cell shows internal problem (ring)	CD8⁺ cytotoxic T cell	T cell says “this is toxic” → kills the cell
MHC-II	Public proposal: APC shows external problem (ring)	CD4⁺ helper T cells	T cells say “let’s rally help!” → immune response activated

---

🧬 Summary:

• MHC-I = Endogenous (inside), kills cell

• MHC-II = Exogenous (outside), activates immune help

What kind of circulatory system do humans have? Blood flow is ____directional which is aided by the ______ and ____ from atrium to ventricle and ____ from ventricles to vasculature

Closed , unidirectional

Atrioventricular valves :Tricuspid and Mitral/Bicuspid valve

Semilunar valves : Pulmonary and aortic valve

The atriums of both sides _____ and the ventricles of both sides ____

Both contract together to squeeze through their respective semilunar valves

What happens during diastole? What about during systole?

Diastole: heart is relaxed and fills blood in both atria

Systole: Atriums contract and ventricles then contract

In systemic circulation blood is _____ and heads to the ____ while in pulmonary circulation, blood is _____ and heads to the ____.

Oxygenated, body

Deoxygenated, lungs

In the lungs the partial pressure of O2(pO2) is ___, which allows for them to ___. The pO2 of the tissues is ____ causing ___

High, bind to heme

Low, be released from heme

The primary driving force for respiration in healthy individuals is ____ pH which is indirectly influenced by _____ levels in the blood.The following equation explains this relation ship: ______.

An increase in carbon dioxide results in a _____ in hydrogen ions which corresponds to a _____ in pH.

1. Decreased

2. Carbon dioxide

3. CO2 +H2O ←→ H2CO3←→ +H + HCO3-

4. Increase

5. Decrease

In order to raise the osmolarity of the filtrate as it descends into the medulla, the ____ can _____. As filtrate ascends from the medulla, osmolarity is lower so initially ___ but _____. Once at the cortex the distal conv tubule ____, but once it approaches the collecting duct it ___. The collecting duct generally

1. Proximal convoluted tubule secrete solutes into the filtrate, specifically HUNK

2. Na and Cl are reabsorbed passively, but since the ascending loop is impermeable to water, they decrease solute concentration through active transport.

3. Only reabsorbs NaCl, and water through aldosterone since the filtrate is much more dilute, but just before it gets to the end it gets more concentrated by dumping the HUNK

4. Becomes more concentrated by reabsorbing water ONLY through ADH activating aquaporins

What are the main layers of skin?

What are the epidermal layers

Good mnemonic for epidermal layers:

Come Let’s Get Sun Burned

How does hydrostatic and oncotic pressure work at capallaries?

Arteries drive blood away from the heart, so the arteriole portion would be higher in hydrostatic pressure. As a result little fluid remains at the venous end which will increase albumin concentration, therefore increasing oncotic pressure which will draw fluid back!

How does Oxygen passively dissolve from the air tin the alveoli into the alveolar capillaries? What about PCO₂ ?

PO₂ in the ambient air must be higher than the PO₂ in the alveoli, and the PO₂ in the alveoli must be higher than the PO₂ in the alveolar capillaries.

PCO₂ is highest in the capillaries and lowest in the lungs!

Bile salts are essential for ___ and are therefore important for ___.

1. Emulsification for fatty compounds

2. fat soluble vitamin absorption

What is the function of trypsin?

Digestion of proteins

What is the function of secretin?

Secretin is a hormone released by the duodenum in response to acidic chyme from the stomach.
It:

• 📤 Stimulates bicarbonate secretion from the pancreas (neutralizes acid)

• ⛔ Inhibits gastric acid secretion

• 🐌 Slows gastric emptying

• 🧴 Stimulates bile production in the liver

💡 Hint: Secretin "secretes" base and slows the acid flow!

What kind of drug could affect macrophages or any other cell like it?

Immunosuppressive drugs

Why do we pee out less than we drink? Also why does our pee get concentrated more than our blood?

We lose water through our sweat and lungs

NOT through blood

We increase water conservation through our kidneys

Whats the point of the blood brain barrier? What cell connection is it like?

Blocks harmful stuff from blood stream to enter brain

TIGHT JUNCTION