Comprehensive Study Notes for Exam Prep

Chapter 17.2: Exam I - Topics for Improvement

• Blood as a Connective Tissue:
  • Blood is the only fluid tissue in the body.
  • It's a connective tissue.
  • Composition:
    • Plasma: 55% (less dense, non-living fluid).
    • Buffy Coat: <1% (leukocytes (WBC) + platelets).
    • Formed Elements: 45% (erythrocytes (RBC), WBCs, and platelets - living blood cells).
• Hematocrit:
  • Percentage of blood volume that is RBCs.
  • Values:
    • Males: $47 \pm 5\%$
    • Females: $42 \pm 5\%$
  • High O2 = Scarlet Color, Low O2 = Dark Color.
• Variations in Hematocrit Values:
  • High:
    • Dehydration, Polycythemia (bone marrow disease), Blood Doping (EPO).
  • Low:
    • Iron deficiency (Anemia), Bleeding.
• Plasma Composition:
  • 90% water.
  • Nutrients, hormones (steroids & peptides), gases (O2, CO2).
  • Glucose, fats, amino acids, urea.
  • Ions: $Na^+, K^+, Ca^{2+}, Mg^{2+}, Cl^-, H^+, HCO_3^-$.
• Plasma Proteins:
  • Mostly produced by the liver.
    • Albumin (60%): Blood buffer, carrier of other molecules, maintains plasma osmotic pressure.
    • Globulins (36%): Transport lipids, metals, and fat-soluble vitamins; act as antibodies (α, β).
    • Fibrinogen (4%): Involved in clotting.
• Red Blood Cells (RBCs):
  • No nucleus or organelles.
  • Plasma membrane protein Spectrin provides flexibility for shape change.
• pH and Volume of Blood:
  • pH: 7.35-7.45.
  • Volume:
    • Males: $5 \pm 1$ L (6 L).
    • Females: $5 - 1$ L (4 L).
• Formed Elements Production:
  • RBCs, WBCs, & platelets.
  • Only WBCs are complete cells.
  • RBCs = No nucleus or organelles Platelets fragments
  • Stem cells divide in Red Bone Marrow to replace.

17.6 Hemostasis: Preventing Blood Loss

• Hemostasis: Process to prevent blood loss due to injury.
• Three Major Steps:
  • Vascular Spasm:
    • Myogenic response.
    • Endothelin & Serotonin release.
    • Activation of nociceptors.
  • Platelet Plug Formation:
    • Exposed collagen fibers from damaged vessel.
    • Adhesion: vWF (von Willebrand factor) stabilizes platelet-collagen adhesion.
    • vWF secreted by endothelial cells & platelets.
    • Platelet Activation: Platelets swell, become spiked & sticky, and release chemicals (ADP, thromboxane A2, fibrinogen, serotonin, histamine, calcium).
    • Recruitment & Platelet Aggregation: ADP & thromboxane A2 recruit other platelets (glycoprotein).
    • Fibrinogen leads to platelet aggregation (sticking together).
    • Serotonin & Histamine: Enhance vascular spasm.
    • Calcium: Required for coagulation.
    • Positive Feedback Mechanism
  • Coagulation (Blood Clotting):
    • Reinforces platelet plug with fibrin threads.
    • Clotting factors (procoagulants): Factors I to XIII, Vitamin K, Calcium ions.
    • Involves a series of procoagulants.
      • Phase 1:
        • Intrinsic & Extrinsic pathways lead to activation of factor X.
      • Phase 2:
        • Factor X complexes with $Ca^{2+}$, PF3, Factor V to form prothrombinase (prothrombin activator).
      • Phase 3:
        • Prothrombin --(Prothrombinase)--> Thrombin.
        • Fibrinogen (Factor I) --(Thrombin (Factor IIa))--> Fibrin (Factor Ia).
        • Fibrin --(Factor XIII + Thrombin + $Ca^{2+}$)--> Fibrin Mesh (Factor XIIIa).
        • Final product: Fibrin mesh.

Clot Retraction and Fibrinolysis

• After clot formation & blood vessel no longer leaking, body stabilizes & removes clot.
• Clot Retraction (30-60 minutes later):
  • Platelets contract (actin & myosin).
  • Fibrin strands pull tight.
  • Clot shrinks, serum squeezed out (serum = plasma - clotting proteins).
  • Wound edges pulled together.
• Blood Vessel Restoration:
  • Platelets release PDGF (Platelet-Derived Growth Factor) & VEGF (Vascular Endothelial Growth Factor).
  • PDGF: rebuild blood vessel wall division of smooth myocytes & fibroblast, rebuild muscle & connective tissue.
  • VEGF: rebuild vessel lining. Stimulate endothelial cells.
• Fibrinolysis (starting ~2 days later):
  • Repairs completed.
  • Plasminogen trapped in clot.
  • Activated into plasmin by tPA, factor XIIa, thrombin (fibrin-digesting enzyme).
  • Plasmin breaks down fibrin.
  • Clot dissolves.
  • Blood flow returns to normal.

Chapter 20.1 Lymphatic System

• Lymph Formation:
  • Originates from interstitial fluid and enters lymphatic capillaries.
  • Lymphatic capillaries are highly permeable.
• Lymph Transport:
  • Lymphatic capillaries --> collecting lymphatic vessel --> Lymph node --> lymphatic trunk --> Lymphatic ducts --> venous System
• Main Lymphatic Ducts:
  • Thoracic Duct:
    • Begins at Cisterna chyli.
    • Empties into left subclavian vein & Internal Jugular vein.
    • Drains most of the body.
  • Right Lymphatic Duct:
    • Empties into right subclavian vein.
    • Drains right upper arm, right head & thorax.
• Lymph Movement Mechanism (Transport):
  • Low-pressure system like the venous system.
    • Skeletal Muscle Contraction (Milking action).
    • Pressure change from breathing (thoracic pump).
    • Pulsations of nearby arteries.
    • Valves prevent backflow.
    • Smooth muscle Contraction in lymphatic vessel walls.
• Obstruction:
  • Lymphedema (swelling).
  • Infection Buboes (swollen lymph nodes).
  • Cancer metastasis: Spread through lymphatic vessel.
• Key Structures in Lymph Transport:
  • Lymph nodes: Filter lymph, activate immune response.
  • Spleen: Filter blood.
  • Thymus: mature T cells. (not lymph directly)
  • MALT (Mucosa-Associated Lymphoid Tissue): Monitor mucosal Surfaces.
    • Tonsil, Peyer's patches, Appendix. No direct lymph filtration.

20.3 Lymph Nodes - Secondary Lymphoid Organs

• Function:
  • Cleansing lymph: Macrophages remove & destroy microorganisms & debris.
  • Immune System activation: Sites for lymphocytes to become activated & mount an attack against antigens.
• Structure:
  • Cortex (Superficial & Deep).
    • Superficial cortex: Contains follicles with germinal centers (location of dividing B cells).
    • Deep cortex: T-cells circulate continuously among blood, lymph nodes, & lymph; abundant dendritic cells (activate both B & T cells).
  • Medulla.
    • Medullary cords (inward): Contains lymphocytes and plasma cells.
    • Medullary Sinus / Lymph Sinus: Found throughout the nodes & consist of large lymphatic capillaries spanned by reticular fibers where macrophages reside.
  • Surrounded by External fibrous capsule which extend inward as trabeculae.
• Lymph Flow:
  • Lymph Enters afferent vessel --> Subscapular Sinus --> Smaller Sinuses (throughout Cortex & Medulla) --> Medullary Sinus --> Hilum via. Efferent vessel.
  • Presence of fewer efferent vessels stagnates (slow) flow.

20.6 Summary of Lymphoid Organs & Tissues

Chapter 21.5 Isotype Switching & Somatic Hypermutation

• Isotype Switching:
  • Occurs when activated B cell receives signal from Helper T cell.
  • Switches antibody production from IgM to another class (IgG, IgA, IgE).
  • DNA recombination at Constant region of Heavy chain gene.
  • Produces antibodies with:
    • Same antigen specificity (same variable region).
    • Different effector functions (e.g., IgG for opsonization, IgA for mucosal immunity, IgE for allergies).
• Somatic Hypermutation:
  • Activated B cell in germinal center of lymph node.
  • Undergoes point mutations in variable (V) regions of antibody gene.
  • Creates B cells with slightly different antigen binding sites (some stronger, some weaker).
  • Selection for B cells with highest affinity for the antigen.
  • Process: Affinity Maturation.
  • Produces memory B cells and plasma cells with high-affinity antibodies.

21.6 Roles of Effector (Specific) T Cells

• CD4 Helper T Cells:
  • Recognize antigen on MHC II (APCs).
  • Differentiate into:
    • TH1: Activates macrophages & cytotoxic T cells (via IFN-$\gamma$).
    • TH2: Stimulate B cell to make antibodies (via IL-4 & IL-5).
    • TH17: Recruits neutrophils & fights extracellular bacteria / fungi (via IL-17).
    • Treg: Suppress immune response & prevent autoimmunity (via IL-10, TGF-β).
• CD8 Cytotoxic T Cells:
  • Recognize antigen on MHC I (all nucleated cells).
  • Activated by APC + IL-2 or IL-2 from helper T cell.
  • Directly kill virus-infected or cancerous cells by:
    • Releasing perforins forming pores in membrane.
    • Releasing granzymes to trigger apoptosis.
• Memory T Cells:
  • Formed after initial activation & response.
  • Long-lived, circulate in blood and lymphoid organs.
  • Respond faster & stronger upon re-exposure to same antigen.

Chapter 18.5 Action Potential of Pacemaker (Nodal) Cells & Sequence of Excitation

• Heart Depolarization and Contraction:
  • Independent NS, Rhythm is altered by ANS.
  • Intrinsic Conduction System: Network of non-contractile cells initiate & distribute impulses.
  • Pacemaker cells (Action Potential Initiation) # Nodal cell #.
• Pacemaker Potential:
  • 1. K+ channel closed, Slow $Na^+$ channel Open. Interior becomes more +ve.
  • 2. Depolarization: $Ca^{2+}$ channel open (Huge influx of $Ca^{2+}$): Rising phase of action potential.
  • 3. Repolarization: K+ channel open, efflux of K+. Cell becomes more negative.
• Sequence of Excitation (-0.22 seconds):
  • Sinoatrial (SA) node --> Atria & ventricles not connected connection b/w Atria & ventricles via gap junctions.
    • Pacemaker of Heart - superial interatrial bundles
    • Depolarizes Fastest - Generate impulse 75/min Sinus rhythm.
  • Atrioventricular (AV) node --> Atria & ventricles not connected connection b/w Atria & ventricles via gap junctions.
    • Right atrial wall / Inferior interatrial Bundl
    • Delays impulse (~0.1 sec): Allows atrial contraction.
    • Inherent rate 50/min (If SA node fails.)
  • AV Bundle (Bundle of His) Carry imploses to apex
    • Through septum, a short distance before it divides.
  • Right & left bundle branches --> Interventricular Septum pathways -superial interventricular.
    * more elaborate on left side of heart more elaborate on left side of heart.
  • Subendocardial conducting Network (Purkinje fibers): Ventricular walls. * Depolanze 30x/min in absence of AV node input.
    • Ventricular contraction follows from apex ~0.22 Sec.

Extrinsic Conduction System & Action Potential of Contractile Cells

• Extrinsic Conduction System - Cardiac Centers in Medulla:
  • Cardiac Acceleratory (Sympathetic):
    • Increase heart rate and force; Stimulate SA/AV nodes, heart muscles, coronary arteries.
  • Cardio Inhibitory (Parasympathetic):
    • Decrease rate & force; Inhibit SA/AV nodes via Vagus nerve.
• Action Potential of Contractile Cells:
  • Responsible for pumping & have a plateau.
    • Depolarization:
      • Open fast voltage-gated $Na^+$ channels. $Na^+$ enters cell.
      • Positive feedback influx of $Na^+$ rises SAP.
      • -90 mV to +30mv
    • Plateau:
      • Open $Ca^{2+}$ channel Slow. At +30 mv $Na^+$ channel close but Slow $Ca^{2+}$ channel open, prolonging depolarization, seen as plateau.
    • Repolarization:
      • After 200 ms, slow $Ca^{2+}$ channel close and voltage-gated $K^+$ channel open. (Rapid efflux of $K^+$) repolarizes cell to RMP.
      • $Ca^{2+}$ are pumped both back into SR and out of cell into ECS.
• Significance:
  • Action potential longer (slower) in cardiac muscle (last 200 ms) than skeletal muscle (1-2 ms).
  • Contraction also occur longer in cardiac muscle (last 200 ms) than in skeletal muscle (last 15-100 ms).
  • Sustained Contraction ensures efficient ejection of blood.
  • Longer refractory period prevents tetanic contractions.
  • #doesn't occur in Cardiac muscle.

18.7 Cardiac Output (CO)

• Cardiac Output (CO):
  • Amount of blood pumped by each ventricle in 1 min.
  • At rest: 5.25 L/min.
  • $CO = HR \times SV$
• Stroke Volume (SV):
  • Volume of blood pumped out by one ventricle per beat.
  • Force Contraction, SV=EDV- ESV
• Regulation of Stroke Volume (SV):
  • Preload:
    • Degree of stretch of heart muscle (Before Contraction).
    • Affects EDV (End-Diastolic Volume).
    • Venous return is most important factor.
    • Frank-Starling law of Heart: ↑Venous Return = ↑Stretches Ventricles.
    • Exercise increases venous return.
    • Slow HR increase stretches ventricles.
  • Contractility:
    • Independent of muscle stretch.
    • Epinephrine stimulate $Ca^{2+}$ release cross-bridge formation.
    • +ve inotropic agents increase contractility.
    • Epi, NE, Glucagon, wich ECFER --> ↑ SV, ↑CO
    • Decrease contractility by negative inotropic agents: $Ca^{2+}$ blockers, Acidosis, increase$K^+$.
  • Afterload:
    • Back pressure exerted by arterial blood.
    • Pressure ventricles overcome to eject.
    • Arterial blood Pressure ↑ESV = ↑CO
    • Aortic Pressure ~80 mm Hg
    • Pulmonary pressure ~8 mm Hg
    • Hypertension increases afterload, resulting in increased ESV, and reduced SV.

Chapter 19.2 Division of Arteries

• Elastic (conducting) Arteries:
  • Thick-walled with large, low-resistance lumen (Aorta & main branches).
  • Blood conduction from Heart to Medium-sized vessel.
  • Elastin found in all three tunics (mostly tunica media).
  • Contain Substantial smooth muscle & inactive in vasoconstriction.
  • Act as pressure reservoirs: expand & recoil as blood is ejected from heart, allow Continuous blood flow downstream.
• Muscular (Distributing) Arteries:
  • Arise after elastic arteries; Deliver blood to body organs; Diameter from pinky-finger size to pencil-lead size.
  • Account for mostly Named arteries. # Thickest tunica Media.
  • More Smooth muscle; less elastic muscle.
  • Active in Vasoconstriction.
• Arterioles (Resistance) Arteries:
  • Smallest of all arteries.
  • larger arterioles contain all three tunics.
  • Smooth muscle Surrounding - Smaller arterioles contains single layer of endothelial cells.
  • Control flow into capillary beds via smooth muscle: changing diameters change resistance to blood flow.

19.6 Definition of Blood Flow, Blood Pressure, and Resistance

• Blood Flow (F): volume flowing through vessel, organ, or entire circulation in a given time period (ml/min).
  • Relatively constant at rest, varies at organ level.

Ch. 22.1 & 22.2 Changes in Epithelium from Upper to Lower Respiratory System

• Nasal Cavity: Pseudostratified Ciliated Columnar Epithelium (P.S. C. C. E)
• Pharynx:
  • Nasopharynx: P.S.C.E
  • Oro & Laryngopharynx: Stratified Squamous Epithelium (S. S. E)
• Larynx:
  • Superior portion: S.S.E
  • Interior to vocal cord: P.S.C.C.E
• Trachea: P.S.C.E
• Bronchi: P.S. C. C. E
• Bronchioles: Cuboidal epithelium
• Alveoli:
  • Type I: Simple Squamous
  • Type II: Cuboidal epithelium

22.4 Pressure Relationships in the Thoracic Cavity

• Atmospheric Pressure (Patm): Exerted by air surrounding the body; 760 mmHg at sea level.

• Intrapulmonary Pressure (Ppul): Pressure within the alveoli; Fluctuates with breathing.

  • Decreases during inspiration; Increases during expiration.
  • Eventually Ppul = Patm.

• Intrapleural Pressure (Pip): Pressure within the pleural cavity; fluctuates with breathing.

  • Always negative pressure; 4 mm less than Ppul; keeps lung inflated.
  • Maintained by Surface tension between parietal & visceral pleurae & lymphatic System draining excess pleural fluid.

• Lung Collapse (Atelectasis): If Pip = Ppul.

• Transpulmonary Pressure (Ppul - Pip): Pressure that keeps lung open.

  • Larger transpulmonary pressure = larger lung volume.
  • If Pip = Ppul, Lung Collapse.

  22.7 CO2 Transport

• Dissolved in Plasma: (7-10%) as $P<em>{CO</em>2}$

• Bound to Hemoglobin: (over 20%) - $CO_2$ binds to globin part of hemoglobin (Carbaminohemoglobin)

• Bicarbonate Ions in Plasma: (70%)

  • $CO<em>2 + H</em>2O \rightleftharpoons H<em>2CO</em>3 \rightleftharpoons HCO_3^- + H^+$ (Use of Carbonic anhydrase)

EXAM III Chapter 23.1-23.2 Overview of the digestive system.

• Six activities of processing of food involves:

  1. Ingestion: Eating.
  2. Propulsion: Peristalsis.
  3. Mechanical Breakdown: Mastication, Mixing ga churning, Segmentation.
  4. Digestion: Catabolic /Enzymes. Saliva.
  5. Absorption: From lumen to blood or lymph.
  6. Defecation: Excretion.

• Histology of alimentary canal.

  • Mucosa
    • Epithelium: Simple Columnar(most of the time); Mouth, esophagus, anus Stratified SSE.
      • Secrete mucus
      • Function: Nourishment and absorption.
    • Lamina Propia: Loose areolar C.T; mucus rich cappillanes
      • Contain lymphoid follicles - defense(MALT).
      • Secrete hormone and enzyme.
    • Musculars mucosa: smooth muscle ; produces local movement mucosa
  • Submucosa
    • Areolar C.T; Submucosal nerve plexus, lymphoid follicles, vessel
  • Muscularis Externa
    • Responsible for segmenta- tion and peristalsis.
    • Inner circular and outer longitud; sphincters in some areas.
  • Serosa
    • Visceral Peritoneum: Areolar CT + Mesothelium
    • Adventitia in Esophagus: Dense c.I + Retroperitoneal have adventitiq & serosa

• Basic concepts of regulating digestion.

  • Mechanical and Chemical stimuli
  • Receptor on Wall- Stretch, osmolarity, pH , substrate & Product
  • Effectors: Smooth muscle and glands--> Reflex activate / inhibit digestive gland

• Neurons & hormone Control (Intrinsic / Extrinsic):

  • Nervous System:
    • Short reflexes (Enteric NS)
    • Extrinsic (ANS)
  • Hormonal Control - Secretion:
    • Food enters Receptors detect it Smooth muscle churns food Digestion occurs

22.5 Digestive Process of the Mouth and Deglutition

 * Propulsion:
  * Deglutition(start) Propulsion through pharynx to esophagus

22.6 Deglutition and Microscopic Anatomy of STOMACH

*Deglutition (Co-ordination of 22 Muscle group)
    *   Buccal Voluntary phase contact of tongue involuntary
    *   Pharyngeal - ecophageal involuntary phase
    *   Controlled by Swallowing Center in lower Pons & medulla and Involve Vagus nerve

• Anatomy of Stomach
  • Mucosa , Sub mucosa, muscular is externa, serosa
  • Simple columnar epithelium (composed of mucus cell)
  • Gastric pits Gastric glands secrete to form Gastric juices acidature
  • Muscularis Externa
    • Longitudinal smooth muscle
    • Circular smooth muscle
    • Oblique Layer
      Types of Gland Cells and Function:
  • Four sercretory cell:
  • Mucous neck cell, Parietal Cell, Chief Cells, Enteroendocrine cell
    • Mucous neck cell:
      • Secrete thin acidic Mucous
    • Parietal Cell
      • $HCl$ Secretion
        • Denature Protein and activate pepsinogen
        • Bactericidal and degrade Cell walls
      • Intrinsic factor:
        • Glycoprotein required for absorption B12 in small intestine
          Chief Cells
          Secrete: Pepsinogen--> Act as Parachines and serotonin and hormone gastrin, lipases.
    • Digest 15%
    • serotonin-->Secrete histamine hormone gastrin and somatostatin

Ale Enterohepatic Circulation and Lipids Digestion:

     *   Bile: Composition contains yellow, green , alkaline solution
* Bile Salts:
    *   Cholesterol derivatives used fo fat emulsification and absorption
*   Bilunbin
    *   (Heme pigment):Bacteria in intestine --> Stereobilin Cholesterol, triglycerides, phospholipids, electrolyte

• Enterohepatic circulation : Conserved bile salts in ileum--> reabsorbed in blood . liver portal vein and is re-secreted
  : 95% recycled and 5% is synthesised
  Lipids Digestion Emulsification --> Digestion --> Micelle formation:
• Emulsification : Pre treatment with bile sats Break large globs into liquid emulsion
  • Digestion : pancreatic Lipase in the gut/ duodenum breaks down the triglycerides
    : Formation of monoglicerides plus two single free fatty acids
    Micelle formation: product in the small intestine coated by products with bile salts
    : 500X compared with droplets smaller emulsions

Fundamentals of the Endocrine System

16. 2
    Receptor with Cell membrane derived AA and Cholestrol derivation
    Target Cell with Microeffect: Protein synthesis, Enzyme Activatation inhibiting, Channel opening closing, Structural Protein
    Macro effect with, Structure & Nutrition, Fuel balance with Electrolytes, Fluid balance, Metabolosm, Reproduction, and Growth &Development
    Classify: Releasing Hormone * Hypothalamos: Tropic/ Non topic Hormone
    AA: Adrenaline and Thyroid
    Chloestrol Steriode Hormose : Gonads: Testestrone, estrogen,Progresterone. Anderdrenal- Adrenaline/Cortisol and Aldoosterone
    *Hormones Secreted from * Adrenal Medulla Pancreas/Intestine - Glucagon/ Insulin * Thyroid gland TSH
    Intracellular Signaling: Secondary Messanger System cAMP

Synthesis/Activation of the Thyroid. & ADH Hormone.

Thyroglobulin synthesised in colloid/follicle Lumen
Thyroglobulin synthesised in follicle lumen
Iodide is trapped 2
3 Iodide oxidized converted to iodine
4 Iodine is attached to tyrosineMediate by
MIT DIT enzyme

S lodinated tyrosine link together to form T3 & T4

• If one MIT & One DIT link, T3 form
  if two DIT link. T4 form 6 Colloid is endocytosed by follicular cells Vessel is then combined with a lysosomeLysosomal enzymes cleave T3 & T4 from thyroglobulinT4 must be lonverted to T3 at tissue level

1. 6 Synthesis/Activation and ADH hormone
   monitor Solute concentration. *Hyperthalamos Secrete oxytocin, ADH, Postener Pituitary, Stored BPHigh concentration ADH cause constriction tubules Reabsorb water/VasopressinLow cause vaso BP, Pain, Srige, Low Prevent urine formation(through/Blood vessels.

Parathyroid Hormone &Insulin

16. 8 Parathyroid hormone.cell clear function by oxyphil not.homeostasisTarget organ by Ca2+ Parathyroid cell skeleton, kidney, Intestine. Osteoclast-Release Ca2Reabsorption of Ca2+ & Secretion PO4^-3 by kidneys Vitamin D by kidneys Intestinal mucosa
    Anabolic Pancreatic is inhibited the level into fat/ B in uptake and in transport and in uptaking glucose into level into is

Glucagon, Insulin and Adrenal Glands

16. Glucagon cell level.in level sympatheticLevel B level level of level
17. Adrenal CortexMacula Densa juxtaglomerate senses in tubular
    Capilleries level uptake to the potent in bloods level

Cortisol Hormones and its Function.

Add Stimulus Trauma stress physical + emotional,infection inflammation
Muscle proteases AA/ Liver Gluconeogensis/+Blood glucose Fat Lipase lipolysis Fatty acid energy for muscle. Cortisol bind to receptors.secretion Pathway to Hypothalamus adrenal, muscle for Traumas Stress inflammation.