Human Anatomy and Physiology
What this domain tests
This domain tests normal structure and function of body systems and how changes produce signs. Expect questions on cells and tissues, blood, heart and circulation, respiration, kidney, digestion, endocrine glands, and reproduction.
Core rules
- Organisation: cells, tissues, organs, and systems. Epithelium covers and lines, connective tissue supports, muscle contracts, and nervous tissue conducts.
- Blood contains plasma, red cells, white cells, and platelets. Hemoglobin carries oxygen; platelets help hemostasis.
- The right side of the heart pumps deoxygenated blood to the lungs; the left side pumps oxygenated blood to the body. Cardiac output = heart rate × stroke volume.
- Inspiration is active through the diaphragm and external intercostals. Gas exchange occurs in alveoli by diffusion.
- Kidney function includes glomerular filtration, tubular reabsorption, secretion, and excretion. Urine formation depends on blood flow and tubular function.
- Insulin lowers blood glucose; glucagon raises it. Thyroid hormone affects metabolism.
Worked example
A person has a heart rate of 70 beats/min and a stroke volume of 70 mL. Cardiac output = 70 × 70 = 4900 mL/min = 4.9 L/min. The reasoning is that cardiac output is volume pumped per minute, so multiply beats per minute by volume per beat. If stroke volume falls, heart rate must rise to maintain output.
Traps
The pulmonary artery carries deoxygenated blood; pulmonary veins carry oxygenated blood. Systemic arteries are usually oxygenated. Do not say urine is formed only by filtration; reabsorption and secretion matter. Do not mix insulin and glucagon actions. Normal values vary, so interpret ranges with the laboratory reference.