Lecture Notes on Human Physiology

These flashcards cover key concepts related to human respiratory, digestive, reproductive, urinary, and nutritional physiology, serving as a study aid for understanding the material.

Dalton’s law of partial pressures

States that the total pressure exerted by a mixture of gases is the sum of the pressures exerted by each gas in the mixture.

Henry’s law

States that when a mixture of gases is in contact with a liquid, each gas will dissolve in the liquid in proportion to its partial pressure.

Age-related changes in respiratory function

Gradual decline in lung structure and function, including weaker airway muscles, loss of alveoli elasticity, reduced diaphragm function, and decreased immune response.

Buccal phase

The voluntary phase of swallowing where chewed food is pushed into the pharynx by the tongue.

Pharyngeal-esophageal phase

The involuntary phase of swallowing controlled by the autonomic nervous system, transporting food from the pharynx into the esophagus.

Defecation reflex

A normal physiological response to rectal distension that leads to the elimination of stool through the anus.

Constipation

Characterized by prolonged intervals between defecation associated with hard stools.

Diarrhea

Characterized by increased frequency of defecation with the excretion of watery stool.

Effects of aging on digestion

Slowed digestive system leading to reduced saliva, weakened esophageal muscles, and decreased stomach elasticity, contributing to issues like constipation and poor nutrient absorption.

Ampulla

A localized dilation of a canal or duct.

Spermatogenesis

The process of sperm formation in males.

Placenta

Temporary organ formed from fetal and maternal tissues that provides nutrients to the developing fetus and removes waste.

Prepuce (foreskin)

Loose skin covering the glans penis.

Estrogen

Hormones that stimulate female secondary sex characteristics.

Scrotum

External sac that encloses the testes.

Ovaries

Female gonads responsible for producing ova and hormones.

Vasectomy

Surgical birth control method where the ductus deferens is cut to prevent sperm release.

Erection

Enlargement and stiffening of the penis due to blood engorgement.

Menopause

Period of life when ovulation and menstruation cease due to hormonal changes.

Progesterone

Hormone that prepares the uterus for a fertilized ovum.

Sperm

Male gamete responsible for fertilization.

Prostate

Accessory reproductive gland that produces part of semen volume.

Puberty

Period when reproductive maturity is achieved.

Climax

Intense pleasure during sexual activity, marked by physiological changes in the body.

Gonads

Primary reproductive organs; testes in males and ovaries in females.

Endoderm

Innermost layer of cells in an embryo that forms the lining of digestive and respiratory tracts.

Penis

Male organ of copulation and urination.

Vagina

Thin-walled tube from the cervix to the exterior, also called the birth canal.

Spermatogonia

Stem cells in testes that divide to produce sperm cells.

Seminal Plasma

Fluid that nourishes sperm and aids in fertilization and pregnancy.

Renal Cortex

Light-colored superficial region of the kidney with a granular appearance.

Renal Pyramids

Cone-shaped masses of the kidney medulla that collect urine.

Nephron

Structural and functional unit of the kidney involving renal corpuscle and tubule.

Aldosterone

Hormone regulating sodium reabsorption and potassium secretion in kidneys.

Antidiuretic hormone (ADH)

Hormone that stimulates kidney reabsorption of water.

Tubular secretion

Movement of substances from blood into renal filtrate.

Tubular excretion

Crucial process where waste is moved from blood into the renal tubule for elimination.

Renal Medulla

Darker region of the kidney containing renal pyramids.

Minor Calyx

Cup-shaped area that drains urine from the renal pyramids.

Major Calyx

Branching extensions collecting urine to drain into the renal pelvis.

Basal Metabolic Rate (BMR)

Rate of energy expenditure required to maintain life.

Thyroxine

Hormone that controls BMR and influences energy expenditure.

Macronutrient

Dietary substances required in large amounts; includes carbohydrates, lipids, and proteins.

Micronutrient

Dietary substances needed in minute amounts; includes vitamins and minerals.

Minerals

Inorganic compounds used in conjunction with enzymes for various body functions.

Vitamins

Organic compounds required in minute amounts that function as coenzymes.

Proteins

Chains of amino acids that serve as structural materials in the body.

Lipids

Fats that provide protection, cushioning, and insulation.

Carbohydrates

Primary fuel source important for ATP and cellular respiration.

Triglycerides

Fats composed of fatty acids; used for energy storage.

Alcohol