Free ITEC Anatomy & Physiology Exam Flashcards

Histology is the microscopic study of tissue structure and organisation. It links each tissue's cellular architecture to the specific function that tissue performs in the body.

Somatic cells divide through four ordered phases - prophase, metaphase, anaphase, and telophase (PMAT). Chromosomes condense in prophase, align centrally in metaphase, separate toward opposite poles in anaphase, and two new nuclei form in telophase.

Diffusion is the passive movement of particles (such as oxygen or dissolved solutes) from an area of higher concentration to an area of lower concentration. Osmosis is the passive movement of water only, across a semi-permeable membrane, from the weaker (more dilute) solution toward the more concentrated one.

Connective tissue binds, supports, and protects other tissues and organs. Its major forms include areolar tissue, adipose (fat) tissue, cartilage, bone, blood, and lymph.

Epithelial tissue covers external body surfaces and lines internal cavities, ducts, and organs. Simple epithelium (squamous, cuboidal, columnar, ciliated) is a single cell layer, while compound epithelium (transitional, stratified) has multiple layers for extra protection.

The skeleton supports the body, anchors muscle attachments, and forms joints for movement. It also protects internal organs, stores calcium, and produces red blood cells (erythrocytes) in bone marrow.

Compact bone is dense and forms the hard outer layer of every bone, including the shaft of long bones, giving strength. Cancellous (spongy) bone is a porous lattice inside the compact bone, found mainly at the ends of long bones, and its spaces hold red bone marrow where blood cells form.

Bones are classified by shape: long (femur), short (carpals), flat (sternum), irregular (vertebrae), and sesamoid (patella). Shape reflects each bone's mechanical role, from leverage to protection.

A ball-and-socket joint (hip, shoulder) allows movement in almost every direction, including rotation. A hinge joint (elbow, knee) allows movement in only one plane - flexion and extension.

Kyphosis is an exaggerated outward curve of the thoracic spine. Lordosis is an exaggerated inward curve of the lumbar spine, and scoliosis is an abnormal sideways curvature of the spine.

Voluntary (skeletal) muscle moves the skeleton under conscious control. Involuntary (smooth) muscle works organs like the gut without conscious input, and cardiac muscle is the involuntary, striated muscle found only in the heart.

The origin is the muscle's fixed attachment point that stays relatively still during contraction. The insertion is the attachment point on the bone that moves when the muscle contracts.

A tendon attaches muscle to bone. A ligament attaches bone to bone, stabilising a joint, and fascia is the sheet of connective tissue that wraps and separates individual muscles.

When muscles work harder than the blood can supply oxygen, they switch to anaerobic respiration and produce lactic acid as a by-product. Its buildup contributes to muscle fatigue, aching, and cramp until rest restores the oxygen supply and the lactic acid is cleared.

A nerve impulse releases calcium ions, which allow myosin heads to attach to actin filaments and pull them inward, shortening the muscle fibre. This cross-bridge cycling repeats using energy from ATP until the nerve signal stops.

From deepest to most superficial, the epidermis has five layers: stratum germinativum (basal layer), stratum spinosum (prickle cell or Malpighian layer), stratum granulosum, stratum lucidum, and stratum corneum. New cells form in the basal layer and are shed as dead, keratinised cells from the corneum.

Ultraviolet light converts a compound in the skin called 7-dehydrocholesterol into vitamin D, which the body needs to absorb calcium. This is one of the skin's functions alongside protection, sensation, and heat regulation.

Eccrine glands are distributed over most of the body and secrete a watery sweat mainly for temperature regulation. Apocrine glands are concentrated in the armpits and groin, become active at puberty, and produce a thicker secretion linked to body odour.

Basal cell carcinoma is the most common and least aggressive skin cancer. Squamous cell carcinoma carries a moderate risk of spreading, while malignant melanoma arises from melanocytes and is the most dangerous, with the highest risk of metastasis.

Vitiligo is an acquired condition where patches of skin lose pigment because melanocytes are destroyed or stop functioning. Albinism is a congenital, genetic condition present from birth in which the body produces little or no melanin in the skin, hair, and eyes.

The heart has two atria (receiving chambers) and two ventricles (pumping chambers). The tricuspid valve (right side) and mitral or bicuspid valve (left side) separate the atria from the ventricles, while the pulmonary and aortic valves control blood leaving the ventricles.

Pulmonary circulation carries deoxygenated blood from the heart to the lungs and returns oxygenated blood to the heart. Systemic circulation then carries that oxygenated blood from the heart to the rest of the body and back.

Erythrocytes (red blood cells) carry oxygen. Leucocytes (white blood cells) defend against infection, and thrombocytes (platelets) trigger clotting to stop bleeding. All three travel suspended in plasma.

Systolic pressure is the higher reading, measured while the ventricles contract and push blood out. Diastolic pressure is the lower reading, measured while the ventricles relax and refill.

Arteriosclerosis is the general hardening, thickening, and loss of elasticity of artery walls, often with age. Atherosclerosis is its most common form, caused by fatty plaque and cholesterol building up inside the artery wall and narrowing the vessel.

The lymphatic system drains excess fluid from body tissues back into the bloodstream and transports lymphocytes that defend against infection. Lacteals in the small intestine also absorb digested fats into the lymph.

The spleen filters blood and recycles old red blood cells. Tonsils and Peyer's patches guard entry points in the throat and gut, while the appendix and lymph nodes support the immune response.

Cervical nodes drain the head and neck, axillary nodes drain the arm, and inguinal and popliteal nodes drain the leg. Swelling in one of these groups often signals infection or inflammation in the area it drains.

Oedema is general fluid buildup in tissue, which can have many causes such as poor circulation or inflammation. Lymphoedema is chronic swelling caused specifically by damage to, or removal of, lymphatic vessels or nodes.

Excess tissue fluid is picked up by lymphatic capillaries and carried through lymphatic vessels and nodes. The thoracic duct drains most of the body into the left subclavian vein, while the right lymphatic duct drains the right arm and right side of the head and chest into the right subclavian vein.

Dendrites receive signals and carry them toward the neurone's cell body. The axon carries the signal away from the cell body, and the synapse is the junction where that signal passes to the next neurone.

The central nervous system (CNS) is the brain and spinal cord. The peripheral nervous system (PNS) is the 12 pairs of cranial nerves and 31 pairs of spinal nerves connecting the CNS to the body, and the autonomic nervous system (ANS) is the involuntary part that controls organ function.

The sympathetic nervous system prepares the body for stress with a 'fight or flight' response, raising heart rate and diverting blood to muscles. The parasympathetic nervous system does the opposite, promoting 'rest and digest' recovery.

The spinal cord gives rise to 31 pairs of spinal nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each pair carries sensory and motor signals to and from a specific body region.

Cranial nerve V (trigeminal) supplies facial sensation and the chewing muscles. Cranial nerve VII (facial) controls the muscles of facial expression, and cranial nerve XI (accessory) supplies the sternocleidomastoid and trapezius muscles of the neck and shoulder.

The anterior pituitary secretes hormones such as growth hormone, thyroid-stimulating hormone, ACTH, prolactin, and the reproductive hormones LH and FSH. The posterior pituitary releases oxytocin and antidiuretic hormone (ADH), which are made in the hypothalamus and only stored in the posterior lobe.

Both hormones come from the Islets of Langerhans in the pancreas. Insulin lowers blood glucose by moving it into cells and storing it as glycogen, while glucagon raises blood glucose by prompting the liver to convert stored glycogen back into glucose.

The thyroid gland secretes thyroxine and triiodothyronine, which set the body's metabolic rate. It also secretes calcitonin, which lowers blood calcium - the opposite of parathormone from the parathyroid glands, which raises it.

The adrenal medulla releases adrenaline and noradrenaline for the immediate stress response. The adrenal cortex releases longer-acting steroid hormones: mineralocorticoids, glucocorticoids, and sex hormones.

Diabetes mellitus is caused by problems with insulin and blood glucose regulation. Diabetes insipidus is unrelated to blood sugar - it results from a lack of antidiuretic hormone (ADH), causing the kidneys to pass excessive dilute urine.

Air enters through the nose and nasal cavity (or the mouth), then passes through the pharynx, larynx, trachea, bronchi, and bronchioles to reach the alveoli. Gas exchange with the blood happens only at the alveoli, the tiny air sacs at the end of the pathway.

External respiration is the exchange of oxygen and carbon dioxide between the air in the alveoli and the blood. Internal respiration is the exchange of those same gases between the blood and the body's cells.

Breathing rate is regulated by the pons Varolii and medulla oblongata in the brain stem. These respiratory centres respond to signals from chemoreceptors, such as rising carbon dioxide in the blood, to automatically adjust the rate and depth of breathing.

Peristalsis is the wave-like muscular contraction that pushes food along the alimentary canal, from the oesophagus through to the rectum. Without it, digestion and elimination could not progress mechanically.

Hydrochloric acid creates the strongly acidic environment the stomach needs to activate pepsin, an enzyme that begins breaking down proteins. This acidic environment also helps destroy many ingested pathogens.

Villi are finger-like projections lining the small intestine that increase surface area for nutrient absorption. Lacteals are the tiny lymphatic vessels inside each villus that specifically absorb digested fats.

Blood is filtered under pressure from the glomerulus into the Bowman's capsule of each nephron. Useful substances such as glucose and water are then reabsorbed into the bloodstream, and the remaining fluid is further adjusted by secretion before leaving as urine.

The VTCT unit specification gives urine as 96% water and 2% urea, with the remaining 2% made up of substances such as ammonia, sodium, potassium, and phosphates. It attributes the yellow colour to the bile pigment bilirubin; strictly, the pigment is urochrome (urobilin), a breakdown product of bilirubin.

The menstrual cycle has three phases: the menstrual phase (uterine lining sheds), the proliferative phase (oestrogen rebuilds the lining while a graafian follicle matures), and the secretory phase (after ovulation the corpus luteum forms and secretes progesterone to prepare the lining for possible pregnancy).

An ectopic pregnancy happens when a fertilised egg implants outside the uterine cavity, most often in a fallopian tube. Because a fallopian tube cannot safely support a growing pregnancy, this is a medical emergency.