Lab Practical

🫀 Vital Signs

4 major vital signs:

• Heart rate (HR)

• Blood pressure (BP)

• Respiratory rate (RR)

• Temperature

❤ Normal Ranges

• Heart Rate (HR): 60–100 bpm (adult resting)

• Blood Pressure (BP): ~120/80 mmHg
  

  • Systolic: 90–120

  • Diastolic: 60–80

🔊 Heart Sounds

Normal:

• S1 (“lub”) → AV valves close (mitral + tricuspid)

• S2 (“dub”) → Semilunar valves close (aortic + pulmonary)

Abnormal:

• Murmurs → turbulent blood flow (valve issues)

• Extra sounds (S3, S4) → can indicate pathology

🩺 Listening Technique

• Called auscultation

• Done using a stethoscope

🩸 Blood Pressure Basics

• Written as: Systolic / Diastolic

• Units: mmHg (millimeters of mercury)

🧪 BP Measurement Techniques

1. Auscultatory method

• Uses stethoscope + cuff

• Listen for Korotkoff sounds

2. Palpatory method

• Uses pulse (no stethoscope)

• Only gives systolic pressure

👉 Difference:

• Auscultatory = systolic + diastolic

• Palpatory = systolic only

🔊 Korotkoff Sounds

• Sounds of blood flowing through artery as cuff pressure changes

• Used to determine BP:
  

  • First sound = systolic

  • Disappearance = diastolic

⚡ Heart Pacemaker

• Sinoatrial (SA) node

• Located in right atrium

🧠 Nervous System Control of Heart

Sympathetic (fight or flight)

• Neurotransmitter: Norepinephrine (NE)

• Receptors: Beta-1 (β1) receptors

• Effect:
  

  • ↑ Heart rate

  • ↑ Contractility

Parasympathetic (rest and digest)

• Neurotransmitter: Acetylcholine (ACh)

• Receptors: Muscarinic receptors

• Effect:
  

  • ↓ Heart rate

🔁 Blood Flow Pathway

Memorize this in order:

Body →

Superior/Inferior vena cava →

Right atrium →

Tricuspid valve →

Right ventricle →

Pulmonary valve →

Pulmonary arteries →

Lungs →

Pulmonary veins →

Left atrium →

Mitral (bicuspid) valve →

Left ventricle →

Aortic valve →

Aorta →

Body

🫁 Oxygenation Rules

• Right side of heart: deoxygenated blood

• Left side of heart: oxygenated blood

Exceptions:

• Pulmonary arteries → deoxygenated

• Pulmonary veins → oxygenated

🫀 Heart Anatomy (Know These!)

Internal Structures

• Atria (R & L)

• Ventricles (R & L)

• Valves:
  

  • Tricuspid

  • Mitral (bicuspid)

  • Pulmonary

  • Aortic

• Chordae tendineae

• Papillary muscles

• Septum

External Structures

• Apex

• Base

• Coronary sulcus

• Great vessels (aorta, pulmonary trunk)

❤ Blood Vessels of the Heart (Coronary Circulation)

• Right coronary artery

• Left coronary artery
  

  • Anterior interventricular artery (LAD)

  • Circumflex artery

• Cardiac veins

• Coronary sinus

🔥 Study Tip

If you want to lock this in fast:

• Memorize blood flow pathway like a story

• Group sympathetic vs parasympathetic side-by-side

• Practice labeling a heart diagram (this is almost always tested)

🧠 Endocrine Histology Lab Review

🧬 4 Major Endocrine Organs (on slides/models)

• Pituitary gland

• Thyroid gland

• Adrenal gland

• Pancreas

🧠 Pituitary Gland (Hypophysis)

🔍 Key Structures

• Anterior pituitary (adenohypophysis) → darker, more cellular

• Posterior pituitary (neurohypophysis) → lighter, fewer cells, more fibers

🎨 Cell Types

• Chromophobes → pale, no stain (inactive cells)

• Chromophils → stain well:
  

  • Acidophils (pink/red)

  • Basophils (purple/blue)

🧪 Acidophils (think “GFL”)

• Growth Hormone (GH)

• Prolactin (PRL)

🧪 Basophils (think “FLAT PiG”)

• FSH

• LH

• ACTH

• TSH

📦 Pituitary Hormones (8 total)

Produced in anterior pituitary:

• GH

• PRL

• TSH

• ACTH

• FSH

• LH

Stored (not made) in posterior pituitary:

• ADH (vasopressin) → made in hypothalamus

• Oxytocin → made in hypothalamus

🦋 Thyroid Gland

🔍 Key Structures

• Follicles → round sacs

• Colloid → pink center inside follicles

• Follicular cells → line follicles

• Parafollicular (C) cells → between follicles

⚖ Cell Types

• Follicular cells
  

  • Produce T3 (triiodothyronine) and T4 (thyroxine)

• Parafollicular (C cells)
  

  • Secrete Calcitonin

🧪 Key Facts

• Major glycoprotein in colloid: Thyroglobulin

• Thyroid hormone precursors:
  

  • Iodinated tyrosine (MIT, DIT)

  • Made by follicular cells

⚡ Adrenal Gland

🔍 Regions

• Cortex (outer) → 3 layers

• Medulla (inner) → center

🧱 Cortex Layers (outer → inner)

“GFR” = Go Find Rex

1. Zona glomerulosa
   

   • Hormone: Aldosterone

   • Class: Mineralocorticoids

3. Zona fasciculata
   

   • Hormone: Cortisol

   • Class: Glucocorticoids (MOST abundant)

5. Zona reticularis
   

   • Hormone: Androgens

   • Class: Gonadocorticoids

⚡ Medulla

• Secretes catecholamines:
  

  • Epinephrine

  • Norepinephrine

👉 Most abundant: Epinephrine

🍬 Pancreas

🔍 Tissue Types

• Exocrine (majority) → acinar cells (digestive enzymes)

• Endocrine (islets of Langerhans) → lighter-staining clusters

🧪 4 Islet Hormones

• Alpha cells → Glucagon

• Beta cells → Insulin (most abundant)

• Delta cells → Somatostatin

• PP cells → Pancreatic polypeptide

🌙 Pineal Gland

🔍 Identification

• Small, irregular gland

• Often has calcified “brain sand” (corpora arenacea)

🧪 Hormone

• Melatonin

🔥 Quick Slide ID Tips (SUPER helpful for lab practical)

• Pituitary: mixed pink/purple cells → anterior vs pale posterior

• Thyroid: round follicles filled with pink colloid

• Adrenal: layered cortex + dark center medulla

• Pancreas: dark acini + pale islets

• Pineal: grainy, calcified look

💡 Fast Memorization Tricks

• Acidophils = “Grow & Produce milk” (GH, PRL)

• Basophils = “FLAT PiG”

• Adrenal layers = GFR

• Pancreas = Alpha (glucose ↑), Beta (glucose ↓)

🩸 BLOOD HISTOLOGY LAB

🧬 What is Blood?

• Type of tissue: Connective tissue

• Liquid medium: Plasma

🔍 Formed Elements (ID on slides)

Erythrocytes (RBCs)

• Alternative name: Red blood cells

• Shape: Biconcave, no nucleus

• Function: Carry O₂ (hemoglobin)

Leukocytes (WBCs)

• Alternative name: White blood cells

• Larger, have nucleus

Platelets

• Alternative name: Thrombocytes

• Cell fragments (clotting)

🧪 Blood Layering (after centrifuge)

1. Plasma (~55%)

2. Buffy coat (<1%)
   

   • WBCs + platelets

4. Erythrocytes (~45%)

👉 Hematocrit: % of blood made up of RBCs (~45%)

🎨 Stain Used

• Wright’s stain (sometimes Wright-Giemsa)

🧠 Leukocyte Order (MOST → LEAST)

“Never Let Monkeys Eat Bananas”

1. Neutrophils

2. Lymphocytes

3. Monocytes

4. Eosinophils

5. Basophils

🧬 Leukocyte Categories

Granulocytes (have granules)

• Neutrophils

• Eosinophils

• Basophils

Agranulocytes (no visible granules)

• Lymphocytes

• Monocytes

❤ EKG (ECG) LAB

⚡ What is an EKG?

• A recording of electrical activity of the heart

🔌 Key Terms

• Lead: Electrical view between electrodes

🔺 Einthoven’s Triangle

• Formed by 3 bipolar limb leads

🔌 3 Bipolar Limb Leads

• Lead I: Right arm → Left arm

• Lead II: Right arm → Left leg

• Lead III: Left arm → Left leg

⚡ Why Ground Electrode?

• Reduces electrical interference → clearer signal

⚖ Einthoven’s Law

👉 Lead II = Lead I + Lead III

📈 EKG Waves (KNOW THIS WELL)

• P wave: Atrial depolarization

• QRS complex: Ventricular depolarization

• T wave: Ventricular repolarization

🔍 Other Features

• PR interval

• ST segment

• QT interval

👉 You should be able to label all of these on a graph

🌬 SPIROMETRY LAB

🫁 2 Major Functions

• Gas exchange (O₂ in, CO₂ out)

• Acid-base balance

💨 Ventilation

• Movement of air in/out of lungs

Inspiration:

• Air in (diaphragm contracts)

Expiration:

• Air out (diaphragm relaxes)

🦴 Structures Used

• Diaphragm

• Intercostal muscles

❤ Respiratory Rate (RR)

• Normal: 12–20 breaths/min

🧪 Spirometer

• Device that measures lung volumes and capacities

🔁 Internal vs External Respiration

• External: Lungs ↔ blood

• Internal: Blood ↔ tissues

⚖ Buffer System

Carbonic Acid–Bicarbonate System:

CO₂ + H₂O ⇌ H₂CO₃ ⇌ H⁺ + HCO₃⁻

• Maintains blood pH

🧪 Normal Blood pH

• 7.35 – 7.45

⚠ Conditions

• Respiratory acidosis: ↑ CO₂ → ↓ pH

• Respiratory alkalosis: ↓ CO₂ → ↑ pH

📊 Lung Volumes (KNOW GRAPH)

Basic Volumes

• Tidal Volume (TV): ~500 mL (normal breathing)

• Inspiratory Reserve Volume (IRV)

• Expiratory Reserve Volume (ERV)

• Residual Volume (RV)

📦 Capacities (made of volumes)

👉 Capacity = 2 or more volumes combined

• Vital Capacity (VC) = TV + IRV + ERV

• Total Lung Capacity (TLC) = VC + RV

• Inspiratory Capacity (IC) = TV + IRV

🔍 Graph Identification

Be able to spot:

• Normal breathing → small waves (TV)

• Deep inhale → IRV

• Forceful exhale → ERV

🔢 Calculations

• Add/subtract volumes to find capacities

• Example:
  VC = TV + IRV + ERV

🔥 FAST REVIEW SUMMARY

• Blood: RBCs = most, buffy coat tiny, plasma largest

• EKG: P = atria, QRS = ventricles, T = recovery

• Spirometry: TV = 500 mL, capacities = combos