GATE Biomedical Engineering Human Anatomy and Physiology Syllabus

How many bones are in the adult human skeleton?

206 bones.

What protein-based sliding mechanism produces skeletal muscle contraction?

The sliding filament theory: actin (thin) filaments slide over myosin (thick) filaments, shortening the sarcomere; this requires ATP and $\ce{Ca^2+}$.

What are the three types of muscle-to-structure connections and joints' main connective tissues?

Tendons connect muscle to bone; ligaments connect bone to bone; cartilage cushions joints. (Tendons transmit muscle force to the skeleton.)

What is the overall balanced equation for cellular (aerobic) respiration?

$$\ce{C6H12O6 + 6O2 -> 6CO2 + 6H2O + energy(ATP)}$$

What is the function of the respiratory system?

To exchange gases between the body and the environment: taking in oxygen and removing carbon dioxide, and aiding in pH regulation and vocalization.

Where does gas exchange occur in the lungs, and by what process?

In the alveoli, by simple diffusion of $\ce{O2}$ and $\ce{CO2}$ across the thin alveolar-capillary membrane along their partial pressure gradients.

What muscle is the primary driver of inhalation, and how does it act?

The diaphragm. It contracts and flattens, increasing thoracic volume and decreasing intrapulmonary pressure, drawing air in (Boyle's law).

What are the components of the human circulatory system?

The heart (pump), blood vessels (arteries, veins, capillaries), and blood (the transport medium).

Trace the path of blood through the four chambers of the heart starting from the body.

Body → right atrium → right ventricle → lungs → left atrium → left ventricle → body. The right side handles deoxygenated blood, the left side oxygenated blood.

What is the difference between arteries and veins?

Arteries carry blood away from the heart (usually oxygenated, under high pressure, thick walls); veins carry blood toward the heart (usually deoxygenated, low pressure, have valves).

What is the formula relating cardiac output, heart rate, and stroke volume?

$$\mathrm{CO} = \mathrm{HR} \times \mathrm{SV}$$ where CO is cardiac output, HR is heart rate, and SV is stroke volume.

Define blood pressure and give the typical normal value for a healthy adult.

Blood pressure is the force exerted by blood against vessel walls; normal is about $120/80\ \mathrm{mmHg}$ (systolic/diastolic).

What is the main function of the excretory (urinary) system?

To remove metabolic nitrogenous wastes (e.g., urea) from the blood and regulate water, electrolyte, and acid-base balance.

What is the functional unit of the kidney?

The nephron. Each kidney contains about one million nephrons that filter blood and form urine.

List the three main processes of urine formation in the nephron.

Glomerular filtration, tubular reabsorption, and tubular secretion.

What is the primary nitrogenous waste excreted by humans?

Urea, produced in the liver from the breakdown of amino acids (via the urea cycle).

What is the function of the endocrine system?

To secrete hormones into the bloodstream that regulate metabolism, growth, reproduction, and homeostasis, providing slow but long-lasting chemical signaling.

Which gland is called the 'master gland' and why?

The pituitary gland, because it secretes hormones that control many other endocrine glands (e.g., thyroid, adrenals, gonads).

Which hormones regulate blood glucose, and from which gland?

Insulin (lowers blood glucose) and glucagon (raises blood glucose), secreted by the islets of Langerhans in the pancreas.

How does endocrine signaling differ from nervous signaling?

Endocrine signaling uses hormones carried by blood (slow onset, long duration, widespread); nervous signaling uses electrical impulses/neurotransmitters (fast, brief, targeted).

What are the two main divisions of the nervous system?

The central nervous system (CNS: brain and spinal cord) and the peripheral nervous system (PNS: nerves outside the CNS).

What is the functional unit of the nervous system, and its three main parts?

The neuron. Its parts are the dendrites (receive signals), the cell body (soma), and the axon (transmits signals).

What is a synapse?

A junction between two neurons (or a neuron and an effector) where a signal is transmitted, usually chemically via neurotransmitters across the synaptic cleft.

What is the approximate resting membrane potential of a typical neuron?

About $-70\ \mathrm{mV}$, maintained largely by the $\ce{Na+}/\ce{K+}$ ATPase pump and ion gradients.

What are the two divisions of the autonomic nervous system and their general roles?

The sympathetic division ('fight or flight') and the parasympathetic division ('rest and digest'); they act antagonistically to maintain homeostasis.

What is the main function of the gastrointestinal (digestive) system?

To ingest, mechanically and chemically break down food, absorb nutrients into the blood, and eliminate undigested waste.

In which organ does most nutrient absorption occur, and what feature increases its surface area?

The small intestine. Villi and microvilli greatly increase its surface area for absorption.

Name two digestive enzymes and the nutrients they break down.

Amylase breaks down starch (carbohydrates) into sugars; pepsin breaks down proteins into peptides. (Lipase digests fats.)

What is the role of the liver and bile in digestion?

The liver produces bile (stored in the gallbladder), which emulsifies fats into smaller droplets to increase the surface area for lipase action.

What is the primary function of the reproductive system?

To produce gametes (sperm and eggs), enable fertilization, and ensure the continuation of the species; it also produces sex hormones.

Name the primary male and female gametes and where each is produced.

Sperm, produced in the testes (males); ova (eggs), produced in the ovaries (females).