Anatomy-and-Physiology MIDTERMS

Alimentary canal

The continuous, hollow muscular tube that winds through the ventral body cavity and is open at both ends.

Digestive system functions

The functions of the digestive system include ingestion, propulsion, food breakdown (mechanical and chemical digestion), absorption, and defecation.

Mouth

The oral cavity proper where food is placed and the tongue, lingual frenulum, and teeth are located.

Esophagus

The muscular tube that connects the pharynx to the stomach and consists of the mucosa, submucosa, muscularis externa, and serosa layers.

Stomach

Acts as a temporary "storage tank" for food and consists of the cardiac region, fundus, body, pylorus, and rugae.

Small intestine

The body's major digestive organ, consisting of the duodenum, jejunum, ileum, ileocecal valve, hepatopancreatic ampulla, microvilli, villi, and Peyer's patches.

Large intestine

Larger in diameter but shorter in length than the small intestine, it functions to dry out indigestible food residue and eliminate it as feces. It includes the cecum, appendix, colon, rectum, and anal canal.

Teeth

Function to tear and grind food, with different types including incisors, canines, premolars, and molars.

Salivary glands

Three pairs of glands (parotid, submandibular, and sublingual) that secrete saliva into the mouth.

Pancreas

Produces enzymes that break down all categories of digestible foods.

Liver

The largest gland in the body that produces bile.

Gallbladder

Stores and concentrates bile produced by the liver.

Kidneys

Filter fluid from the bloodstream, process filtrate, eliminate waste, regulate blood volume and chemical makeup, and produce renin and erythropoietin.

Nephrons

The structural and functional units of the kidneys, consisting of glomerulus, renal tubule, Bowman's capsule, podocytes, proximal convoluted tubule, loop of Henle, and distal convoluted tubule.

Ureters

Passageways that carry urine from the kidneys to the bladder through peristalsis.

Urinary bladder

A muscular sac that stores urine temporarily and contains the detrusor muscles and transitional epithelium.

Urethra

A thin-walled tube that carries urine from the bladder to the outside of the body, controlled by the internal and external urethral sphincters.

Glomerular filtration

The process in which water and solutes smaller than proteins are forced through the capillary walls and pores of the glomerular capsule into the renal tubule.

Tubular reabsorption

The process in which water, glucose, amino acids, and needed ions are transported out of the filtrate into the tubule cells and then enter the capillary blood.

Tubular secretion

The process in which hydrogen, potassium, creatinine, and drugs are removed from the peritubular blood and secreted by the tubule cells into the filtrate.

Micturition

The act of emptying the bladder.

Accumulation

The process in which the bladder continues to collect urine until about 200 ml have accumulated.

Activation

The stretching of the bladder wall activates stretch receptors.

Transmission

Impulses transmitted to the sacral region of the spinal cord and then back to the bladder via the pelvic splanchnic nerves cause the bladder to go into reflex contractions.

External sphincter

skeletal muscle and voluntarily controlled, allowing us to choose to keep it closed or relax it to release urine from the body.

Endocrine System

The system responsible for regulating various bodily functions through the secretion of hormones.

Ion management

The endocrine system regulates the concentrations of sodium, potassium, and calcium ions in the blood.

Direct gene activation

Steroid hormones can diffuse through plasma membranes of target cells, enter the nucleus, and activate specific genes to transcribe messenger RNA, resulting in the synthesis of new proteins.

Second messenger system

Water-soluble hormones bind to receptors on target cell membranes and utilize a second messenger system to transmit signals within the cell.

Hypothalamus

Part of the nervous system and a major endocrine organ that produces several hormones; an important autonomic nervous system and endocrine control center located inferior to the thalamus.

Pituitary gland

A pea-sized gland that hangs from the inferior surface of the hypothalamus and consists of the anterior pituitary (glandular tissue) and the posterior pituitary (nervous tissue).

Growth hormone (GH)

A hormone that promotes the growth of skeletal muscles and long bones and stimulates most target cells to grow in size and divide.

Prolactin (PRL)

A hormone that stimulates and maintains milk production by the breast after childbirth.

Adrenocorticotropic hormone (ACTH)

A hormone that regulates the endocrine activity of the adrenal cortex.

Thyroid-stimulating hormone (TSH)

A hormone that influences the growth and activity of the thyroid gland.

Gonadotropic hormones

Hormones that regulate the hormonal activity of the gonads (ovaries and testes).

Follicle-stimulating hormone (FSH)

A hormone that stimulates follicle development in the ovaries and sperm development in the testes.

Luteinizing hormone (LH)

A hormone that triggers ovulation in females and stimulates testosterone production in males.

Oxytocin

A hormone released during childbirth and nursing that stimulates uterine contractions, sexual relations, breastfeeding, and milk ejection.

Antidiuretic hormone (ADH)

A hormone that causes the kidneys to reabsorb more water, decreasing urine volume and increasing blood volume; also known as vasopressin.

Thyroid gland

A hormone-producing gland located at the base of the throat that produces thyroxine (T4), triiodothyronine (T3), and calcitonin.

Thyroxine (T4)

The major hormone secreted by the thyroid gland that controls the rate of glucose oxidation and tissue growth and development.

Epidermis

The outermost layer of the skin, composed of up to five layers or strata.

Melanin

A pigment produced by melanocytes in the stratum basale of the epidermis, responsible for skin color.

Dermis

The layer of skin beneath the epidermis, composed of collagen and elastic fibers.

Collagen

Fibers in the dermis that provide toughness and hydration to the skin.

Elastic fibers

Fibers in the dermis that give the skin its elasticity.

Sebaceous glands

Exocrine glands in the skin that produce sebum, an oily substance that keeps the skin soft and moist.

Hair follicle

Structure in the skin that produces hair.

Nails

Scalelike modifications of the epidermis that cover the tips of fingers and toes.

Lunula

The white crescent-shaped region at the base of the nail.

Melanin

Pigment in the epidermis that contributes to skin color.

Carotene

Pigment deposited in the skin that gives it a yellow-orange cast.

Hemoglobin

Oxygen-rich pigment in the dermal blood vessels that contributes to skin color.

Redness or erythema

Reddened skin, which may indicate various conditions such as inflammation or fever.

Pallor or blanching

Pale skin, which may indicate stress or certain medical conditions.

Jaundice

Abnormal yellow skin tone, usually indicating a liver disorder.

Bruises

Black-and-blue marks on the skin caused by clotted blood.

Hair growth cycle

The three stages of hair growth and shedding:anagen, catagen, and telogen.

Nervous system

The complex network of cells and tissues that transmit signals throughout the body.

Central nervous system (CNS)

The brain and spinal cord, which act as the integrating and command centers of the nervous system.

Peripheral nervous system (PNS)

Nerves that extend from the brain and spinal cord, outside of the CNS.

Sensory division

Nerves that convey impulses from sensory receptors to the CNS.

Motor division

Nerves that carry impulses from the CNS to muscles and glands.

Supporting cells

Cells in the nervous system that support, insulate, and protect neurons.

Neurons

Nerve cells specialized to transmit messages (nerve impulses) throughout the body.

Cell body

The metabolic center of a neuron.

Processes

Armlike fibers of a neuron that transmit messages.

Myelin sheaths

Fatty coverings that protect and insulate nerve fibers, increasing the transmission rate of nerve impulses.

Nodes of Ranvier

Gaps in the myelin sheath of a nerve fiber.

Sensory neurons

Neurons that carry impulses from sensory receptors to the CNS.

Motor neurons

Neurons that carry impulses from the CNS to muscles and glands.

Cerebral hemispheres

The largest region of the brain, responsible for higher mental functions.

Parietal lobe

The lobe of the cerebral hemisphere that contains the primary somatic sensory area.

Occipital lobe

The lobe of the cerebral hemisphere that contains the visual area.

Temporal lobe

The lobe of the cerebral hemisphere that contains the auditory and olfactory areas.

Frontal lobe

The lobe of the cerebral hemisphere that contains the primary motor area and Broca's area.

Diencephalon

The region of the brain that sits atop the brain stem and includes the thalamus and hypothalamus.

Thalamus

The relay station for sensory impulses passing upward to the sensory cortex.

Hypothalamus

The autonomic nervous system center that regulates body temperature, water balance, and metabolism.

Brain stem

The region of the brain that includes the midbrain, pons, and medulla oblongata.

Cerebellum

The region of the brain responsible for precise timing of muscle activity and balance.

Meninges

The three layers of protective membranes that surround the brain and spinal cord.

Dura mater

The outermost layer of the meninges, a double-layered membrane.

Falx cerebri

A fold of the inner dural membrane that attaches the brain to the cranial cavity.

Tentorium cerebelli

A structure that separates the cerebellum from the cerebrum.

Arachnoid mater

The middle layer of the meninges that has threadlike extensions spanning the subarachnoid space.

Pia mater

The innermost meningeal layer that tightly clings to the surface of the brain and spinal cord.

Cerebrospinal Fluid (CSF)

A watery "broth" similar to blood plasma that surrounds and protects the brain and spinal cord.