These anatomy and physiology notes for nursing cover every body system in the order most nursing syllabi follow, with the normal values, tables and one-line facts that keep coming back in AIIMS NORCET, staff nurse, CHO and ANM papers. Use them for quick revision after you have read a standard textbook such as Ross and Wilson or Tortora.
Anatomy and physiology rarely appears as a large separate section in recruitment exams, but it sits underneath almost every clinical question. A question on digoxin, a lumbar puncture or a thyroidectomy complication is really a question on the heart, the spinal cord or the parathyroid glands.
Scope and weightage of anatomy and physiology notes for nursing exams
In NORCET and most nursing officer exams, pure anatomy and physiology questions form a modest share of the paper, while applied questions (normal values, nerve supply of injection sites, conduction system, hormone functions) are spread across medical-surgical, paediatric and obstetric sections. CHO and ANM papers ask more direct factual questions. Read this page together with the medical surgical nursing notes, because most disorders there build on the normal physiology below.
Cells and tissues
- Cell membrane: phospholipid bilayer, selectively permeable.
- Mitochondria: site of aerobic respiration and ATP production (the “powerhouse”).
- Ribosomes: protein synthesis. Golgi apparatus: packaging and secretion. Lysosomes: digestive enzymes (called “suicide bags”).
- Nucleus: contains DNA; human somatic cells have 46 chromosomes (23 pairs), gametes have 23.
- Transport: diffusion and osmosis are passive; the sodium-potassium pump moves 3 Na+ out and 2 K+ in using ATP.
The four basic tissue types are epithelial, connective, muscular and nervous. Simple squamous epithelium lines alveoli and blood vessels (endothelium), stratified squamous covers skin and oesophagus, and transitional epithelium lines the urinary bladder so it can stretch.
Skeletal system
- An adult skeleton has 206 bones; a newborn has about 270 to 300, which fuse with age.
- Longest and strongest bone: femur. Smallest bone: stapes (middle ear).
- Vertebral column: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused into the sacrum) and 4 coccygeal (fused into the coccyx), so 33 vertebrae forming 26 bones in adults.
- C1 is the atlas, C2 the axis. Ribs: 12 pairs (7 true, 3 false, 2 floating).
- Osteoblasts build bone, osteoclasts resorb bone, osteocytes are mature bone cells.
| Synovial joint type | Example |
|---|---|
| Ball and socket | Shoulder, hip |
| Hinge | Elbow, knee, interphalangeal joints |
| Pivot | Atlanto-axial joint, proximal radio-ulnar joint |
| Saddle | Carpometacarpal joint of the thumb |
| Condyloid (ellipsoid) | Wrist (radiocarpal) joint |
| Plane (gliding) | Intercarpal joints |
Muscular system
| Type | Control | Appearance | Location |
|---|---|---|---|
| Skeletal | Voluntary | Striated, multinucleated | Attached to bones |
| Cardiac | Involuntary | Striated, intercalated discs | Heart |
| Smooth | Involuntary | Non-striated | Walls of hollow organs, vessels |
- Contraction follows the sliding filament mechanism: calcium binds troponin, exposing binding sites on actin for myosin heads; ATP is needed for both contraction and relaxation.
- Neuromuscular junction transmitter: acetylcholine.
- Largest muscle: gluteus maximus. Longest: sartorius. Smallest: stapedius.
- Applied: the vastus lateralis is the preferred IM site in infants; the ventrogluteal site is preferred in adults because it avoids the sciatic nerve. See the fundamentals of nursing notes for injection sites and angles.
Cardiovascular system
The heart has four chambers and four valves. The tricuspid valve lies between the right atrium and right ventricle, the mitral (bicuspid) valve between the left atrium and left ventricle, and the pulmonary and aortic semilunar valves guard the outflow tracts. The left ventricle has the thickest wall because it pumps into the systemic circulation.
Conduction system
SA node, then internodal pathways, then AV node, then bundle of His, then right and left bundle branches, then Purkinje fibres.
| Pacemaker site | Intrinsic rate (beats/min) |
|---|---|
| SA node (natural pacemaker) | 60 to 100 |
| AV node / junction | 40 to 60 |
| Ventricles (Purkinje fibres) | 20 to 40 |
ECG and heart sounds
- P wave: atrial depolarisation. QRS complex: ventricular depolarisation (atrial repolarisation is hidden in it). T wave: ventricular repolarisation.
- Normal PR interval 0.12 to 0.20 seconds; normal QRS duration less than 0.12 seconds.
- S1 (“lub”): closure of the mitral and tricuspid valves at the start of systole. S2 (“dub”): closure of the aortic and pulmonary valves.
- Coronary arteries arise from the aorta and fill mainly during diastole.
Normal cardiovascular values
| Parameter | Normal adult value |
|---|---|
| Heart rate | 60 to 100 beats/min |
| Blood pressure | About 120/80 mmHg |
| Stroke volume | About 70 mL |
| Cardiac output (HR x SV) | About 5 L/min |
| Mean arterial pressure | 70 to 100 mmHg; MAP = (SBP + 2 x DBP) / 3 |
Respiratory system
- The right lung has 3 lobes, the left lung 2 (with the cardiac notch and lingula).
- The right main bronchus is shorter, wider and more vertical, so aspirated foreign bodies usually enter the right lung.
- Surfactant is secreted by type II pneumocytes and reduces surface tension; deficiency in preterm babies causes respiratory distress syndrome.
- Respiratory centres lie in the medulla oblongata and pons. The main stimulus to breathe is a rise in CO2 (via central chemoreceptors).
- About 97 to 98 percent of oxygen is carried bound to haemoglobin. Most CO2 (about 70 percent) is carried as bicarbonate.
| Lung volume | Approximate adult value |
|---|---|
| Tidal volume | 500 mL |
| Inspiratory reserve volume | About 3000 mL |
| Expiratory reserve volume | About 1100 mL |
| Residual volume | About 1200 mL |
| Vital capacity (TV + IRV + ERV) | About 4600 mL |
| Total lung capacity | About 5800 mL |
| Anatomical dead space | About 150 mL |
Normal adult respiratory rate is 12 to 20 breaths per minute.
Digestive system
- Small intestine: about 6 m (duodenum about 25 cm, jejunum and ileum make up the rest). Large intestine: about 1.5 m.
- Liver: largest gland of the body. It produces bile, which is stored and concentrated in the gall bladder and emulsifies fat.
- Stomach cells: parietal (oxyntic) cells secrete HCl and intrinsic factor, chief cells secrete pepsinogen, G cells secrete gastrin.
- Intrinsic factor is needed for vitamin B12 absorption in the terminal ileum; its loss causes pernicious anaemia.
- Iron is absorbed mainly in the duodenum.
- Salivary amylase (ptyalin) starts starch digestion; pancreatic juice contains trypsinogen, lipase and amylase.
- Large intestine absorbs water and electrolytes; colonic bacteria synthesise vitamin K.
Renal (urinary) system
- Each kidney has about 1 million nephrons. The right kidney sits slightly lower because of the liver.
- The kidneys receive about 20 to 25 percent of cardiac output.
- Glomerular filtration rate: about 125 mL/min (about 180 L/day), but only 1 to 2 L of urine is passed per day.
- Minimum acceptable adult urine output: 0.5 mL/kg/hour (about 30 mL/hour).
- Normal urine specific gravity about 1.005 to 1.030; urine pH is usually slightly acidic (around 6).
- Juxtaglomerular cells secrete renin. The kidney also secretes erythropoietin and activates vitamin D.
- ADH acts on the collecting ducts to reabsorb water; aldosterone acts on the distal tubule and collecting ducts to retain sodium and excrete potassium.
- Female urethra is about 4 cm; male urethra about 18 to 20 cm. Short female urethra explains more frequent UTIs.
Endocrine system
| Gland | Hormones | Excess | Deficiency |
|---|---|---|---|
| Anterior pituitary | GH, TSH, ACTH, FSH, LH, prolactin | GH: gigantism (children), acromegaly (adults) | GH: pituitary dwarfism |
| Posterior pituitary | ADH, oxytocin (made in the hypothalamus, stored here) | ADH: SIADH | ADH: diabetes insipidus |
| Thyroid | T3, T4, calcitonin | Hyperthyroidism (Graves disease) | Congenital hypothyroidism (cretinism), myxoedema in adults |
| Parathyroid | Parathormone (raises serum calcium) | Hypercalcaemia, renal stones | Hypocalcaemia, tetany |
| Adrenal cortex | Aldosterone, cortisol, androgens | Cushing syndrome, Conn syndrome | Addison disease |
| Adrenal medulla | Adrenaline, noradrenaline | Phaeochromocytoma | Not clinically significant |
| Pancreas (islets) | Insulin (beta), glucagon (alpha), somatostatin (delta) | Hypoglycaemia (insulinoma) | Diabetes mellitus |
| Pineal | Melatonin | Regulates sleep and circadian rhythm | |
The adrenal cortex has three zones from outside in: zona glomerulosa (aldosterone), zona fasciculata (cortisol) and zona reticularis (androgens). The pituitary is often called the master gland, but it is itself controlled by the hypothalamus.
Nervous system
- CNS: brain and spinal cord. PNS: 12 pairs of cranial nerves and 31 pairs of spinal nerves (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal).
- Myelin is formed by Schwann cells in the PNS and oligodendrocytes in the CNS.
- The spinal cord ends at about L1 to L2 in adults, so lumbar puncture is done at the L3 to L4 or L4 to L5 space.
- CSF is produced by the choroid plexus (about 500 mL/day) with a total volume of about 150 mL at any time.
- Medulla oblongata: cardiac, respiratory and vasomotor centres. Cerebellum: balance, posture and coordination. Hypothalamus: temperature, thirst, hunger and pituitary control.
- Broca’s area (frontal lobe): motor speech. Wernicke’s area (temporal lobe): understanding speech. Occipital lobe: vision.
Cranial nerves table
| No. | Nerve | Type | Key function |
|---|---|---|---|
| I | Olfactory | Sensory | Smell |
| II | Optic | Sensory | Vision |
| III | Oculomotor | Motor | Most eye movements, pupil constriction, eyelid elevation |
| IV | Trochlear | Motor | Superior oblique muscle (smallest cranial nerve) |
| V | Trigeminal | Mixed | Facial sensation, muscles of chewing (largest cranial nerve) |
| VI | Abducens | Motor | Lateral rectus muscle |
| VII | Facial | Mixed | Facial expression, taste from anterior two-thirds of tongue (affected in Bell’s palsy) |
| VIII | Vestibulocochlear | Sensory | Hearing and balance |
| IX | Glossopharyngeal | Mixed | Taste from posterior one-third of tongue, gag reflex, swallowing |
| X | Vagus | Mixed | Parasympathetic supply to heart, lungs, gut (longest cranial nerve) |
| XI | Accessory | Motor | Sternocleidomastoid and trapezius |
| XII | Hypoglossal | Motor | Tongue movement |
Reproductive system
- Spermatozoa form in the seminiferous tubules and mature in the epididymis. Sertoli cells nourish sperm; Leydig (interstitial) cells secrete testosterone.
- In a 28-day cycle, ovulation occurs around day 14 and is triggered by the LH surge.
- Fertilisation normally occurs in the ampulla of the fallopian tube.
- After ovulation the corpus luteum secretes progesterone; if pregnancy occurs, hCG maintains it.
- FSH stimulates follicle growth in females and spermatogenesis in males.
Menstrual cycle phases, fetal circulation and placental physiology are covered in the obstetrics and gynaecology nursing notes.
Special senses
- Retina: rods for dim light and night vision (rhodopsin, needs vitamin A), cones for colour and sharp vision.
- Fovea centralis: area of sharpest vision, cones only. Optic disc: blind spot, no photoreceptors.
- Aqueous humour is produced by the ciliary body and drains through the canal of Schlemm; blockage raises intraocular pressure (glaucoma). Normal IOP is about 10 to 21 mmHg.
- Ear ossicles: malleus, incus, stapes. The organ of Corti in the cochlea is the organ of hearing.
- Semicircular canals detect rotational movement; the utricle and saccule detect head position.
- The Eustachian tube links the middle ear to the nasopharynx; it is shorter and more horizontal in children, so otitis media is common.
Blood and normal values
Blood makes up about 7 to 8 percent of body weight (about 5 L in an adult). Plasma is about 55 percent of blood volume, formed elements about 45 percent.
| Parameter | Normal adult value |
|---|---|
| Haemoglobin | Men 13 to 17 g/dL; women 12 to 15 g/dL |
| RBC count | Men 4.5 to 5.5 million/mm3; women 4.0 to 5.0 million/mm3 |
| Total WBC count | 4,000 to 11,000/mm3 |
| Platelets | 1.5 to 4 lakh/mm3 |
| Haematocrit (PCV) | Men about 40 to 50 percent; women about 36 to 46 percent |
| Blood pH | 7.35 to 7.45 |
| Fasting blood glucose | 70 to 100 mg/dL |
| Serum sodium | 135 to 145 mEq/L |
| Serum potassium | 3.5 to 5.0 mEq/L |
| Serum calcium | 8.5 to 10.5 mg/dL |
| Serum creatinine | About 0.6 to 1.2 mg/dL |
| Prothrombin time | About 11 to 13.5 seconds (INR about 1) |
- RBC lifespan: 120 days. Platelet lifespan: about 7 to 10 days.
- Differential count: neutrophils are the most numerous WBCs (about 40 to 70 percent), basophils the least (0 to 1 percent). Eosinophils rise in allergy and worm infestation.
- Vitamin K-dependent clotting factors: II, VII, IX and X. Factor VIII deficiency causes haemophilia A; factor IX deficiency causes haemophilia B (Christmas disease).
- Blood group AB positive is the universal recipient; O negative is the universal donor for red cells.
Quick revision points
- Natural pacemaker of the heart: SA node (60 to 100 beats/min).
- Thickest heart chamber wall: left ventricle.
- Normal PR interval: 0.12 to 0.20 seconds.
- Normal tidal volume: about 500 mL.
- Surfactant is produced by type II pneumocytes.
- Foreign bodies commonly lodge in the right main bronchus.
- Intrinsic factor is secreted by parietal cells of the stomach.
- Vitamin B12 is absorbed in the terminal ileum.
- Normal GFR: about 125 mL/min.
- Renin is secreted by the juxtaglomerular cells of the kidney.
- ADH and oxytocin are synthesised in the hypothalamus.
- Largest cranial nerve: trigeminal (V). Longest: vagus (X). Smallest: trochlear (IV).
- Bell’s palsy affects the facial nerve (VII).
- Adult spinal cord ends at about L1 to L2.
- Smallest bone: stapes. Longest bone: femur.
- RBC lifespan: 120 days.
- Haemophilia A: factor VIII deficiency.
- Night blindness: vitamin A deficiency affecting rhodopsin in rods.
Common MCQ traps
- ADH is released from the posterior pituitary but produced in the hypothalamus. Read the verb in the question.
- S1 is the closure of AV valves, not the semilunar valves.
- Vital capacity does not include residual volume; total lung capacity does.
- Calcitonin lowers serum calcium; parathormone raises it.
Once these basics are firm, move on to the pharmacology notes for nursing, where receptor and organ physiology explain most drug actions and side effects. For a full study plan that places this subject in your timetable, read the NORCET preparation strategy.
If you want guided teaching, the AIIMS NORCET courses and staff nurse and nursing officer courses cover anatomy and physiology alongside clinical subjects. Test yourself with the NORCET test series or the staff nurse test series, and keep the free nursing PDF notes for last-minute revision.
Frequently asked questions
Are anatomy and physiology questions asked in NORCET?
Yes, but mostly in an applied form. Expect questions on normal values, conduction of the heart, cranial nerves, hormones and injection site anatomy, often blended with clinical scenarios.
Which book is best for anatomy and physiology for nursing exams?
Ross and Wilson Anatomy and Physiology in Health and Illness and Tortora’s Principles of Anatomy and Physiology are widely used standard texts. Use one textbook for concepts and short notes like these for revision.
Which normal values must I memorise?
Vital signs, haemoglobin, WBC and platelet counts, serum sodium, potassium and calcium, blood glucose, ABG values, GFR and urine output. These appear across subjects, not only in anatomy.
How should I revise anatomy and physiology quickly?
Revise system-wise using tables, then solve topic-wise MCQs on the same day. Re-test weak systems after a week with a mock test.
Prepare with Concept RNA
Turn these anatomy and physiology notes into marks with structured classes, subject-wise tests and full-length mocks built for nursing recruitment exams.