Anatomy and Physiology Fundamentals

• Anatomy is the study of the structure of the human body.

Organization Levels

• The chemical level comprises atoms like C, H, O, N, P and molecules such as DNA.
• The cellular level involves cells, which are groups of molecules and organelles.
• The tissue level is where similar cells group together; four basic tissue types are epithelial, connective, muscular, and nervous.
• The organ level includes organs, a group of different tissues working together.
• The system level is where organs interact in organ systems.
• An organism level is a human.
• The human body has 11 organ systems.

Integumentary System

• Hair, skin, and nails are components.
• It protects the body from the external environment.
• Produces vitamin D.
• Retains water.
• Regulates body temperature.

Skeletal System

• Bones and joints are components.
• Supports the body.
• Protects internal organs.
• Provides leverage for movement.
• Produces blood cells.
• Stores calcium salts.

Muscular System

• Skeletal muscles are components.
• Produces movement.
• Controls body openings.
• Generates heat.

Nervous System

• Brain, spinal cord, and nerves are components.
• Regulates body functions.
• Sensation, movement, automatic functions, and higher mental functions are provided through nerve impulses.

Endocrine System

• The pineal gland, hypothalamus, pituitary gland, thyroid gland, thymus gland, adrenal glands, pancreas, ovaries (female), and testes (male) are components.
• It regulates body functions.
• Regulates the functions of muscles, glands, and other tissues through hormone secretion.

Cardiovascular System

• Blood vessels and the heart are components.
• It pumps and delivers oxygen-poor blood to the lungs and oxygen-rich blood to the tissues.
• Removes wastes from tissues.
• Transports cells, nutrients, and other substances.

Lymphatic System

• Tonsils, lymph nodes, thymus, spleen, and lymphatic vessels are components.
• Returns excess tissue fluid to the cardiovascular system.
• Provides immunity (protection against disease).

Respiratory System

• The nasal cavity, pharynx, larynx, trachea, and lungs are components.
• Delivers oxygen to the blood.
• Removes carbon dioxide from the body.
• Maintains blood's acid-base balance.

Digestive System

• The mouth, salivary glands, esophagus, liver, stomach, gallbladder, pancreas, large intestine, and small intestine are components.
• Digests food.
• Absorbs nutrients into the blood.
• Removes food waste.
• Regulates fluid, electrolyte, and acid-base balance.

Urinary System

• Kidneys, ureters, urinary bladder, and urethra are components.
• Removes metabolic wastes from the blood.
• Regulates fluid, electrolyte, and acid-base balance.
• Stimulates blood cell production.

Reproductive System (Male)

• The prostate gland, ductus deferens, testis, and penis are components.
• Produces and transports sperm.
• Secretes hormones.
• Facilitates sexual function.

Reproductive System (Female)

• Mammary glands, uterine tube, ovary, uterus, and vagina are components.
• Produces and transports eggs.
• Acts as the site of fetal development, fetal nourishment, childbirth, and lactation.
• Secretes hormones.
• Facilitates sexual function.

Study of the Human Body

• Surface anatomy studies surface markings of the body.
• Gross anatomy examines structures visible without aid.
• Microscopic anatomy studies structures needing a microscope.
• Histology focuses on the study of tissues.
• Cytology focuses on the study of cells.
• Physiology's subfields are classified by organ or organ system.
• Neurophysiology studies the brain and nerves.
• Cardiovascular physiology studies the heart and blood vessels.

Anatomical Position

• The common reference is used to describe body parts and regions.
• The body is standing upright.
• Feet are shoulder width apart.
• Upper limbs are at the sides of the trunk.
• The head and palms face forward.
• The body is referred to as if in anatomical position, even if in another position.
• Right and left refer to the body being described, not one’s own.
• In males in the anatomical position, the penis is described in its erect position, lying against the abdomen, with the dorsal surface being anterior when flaccid.

Directional Terms

• Directional terms are used to ensure accurate communication, describing the relative location of body parts.
• Anterior refers to the front.
• Posterior refers to the back.
• Superior means toward the head.
• Inferior means closer to the feet.
• Proximal refers to being closer to the point of origin.
• Distal refers to being more distant from the same point of origin.
• The body's midline is an imaginary line running down the middle.
• Medial refers to a position closer to the midline.
• Lateral refers to a position that is further away.
• Superficial refers to structures closer to the body's surface.
• Deep refers to structures further away

Planes of Section

• Sagittal plane divides the body into right and left sections.
• Midsagittal plane divides the body into equal left and right sections.
• Parasagittal plane divides the body into unequal right and left sections.
• Frontal (coronal) plane divides the body into anterior and posterior sections.
• Transverse (horizontal) plane divides the body into superior and inferior sections.
• The oblique plane is useful for examining structures difficult to examine with the three primary planes.

Body Cavities and Membranes

• The dorsal body cavity is on the posterior side, with the cranial cavity containing the brain, and the vertebral (spinal) cavity containing the spinal cord.
• The ventral body cavity is separated by the diaphragm into the thoracic and abdominopelvic cavities.
• The thoracic cavity is superior to the diaphragm.
• The abdominopelvic cavity is inferior to the diaphragm.
• The pleural cavities surround each lung.
• The mediastinum is between the pleural cavities and houses the heart, great vessels (pulmonary trunk and aorta), trachea, and esophagus.
• Serous membranes form three main types of three serous body cavities.
• The outer parietal pleura and inner visceral pleura line the thoracic wall and lungs, respectively.
• The thin space between them forms the pleural cavity.
• The outer parietal pericardium separates the heart from the mediastinum, and the inner visceral pericardium covers the heart.
• The space created by these membranes forms the pericardial cavity.
• The peritoneal membranes surround some abdominal organs, with the outer parietal and inner visceral layers forming a peritoneal cavity, while some organs lie outside and are called retroperitoneal.
• The superior abdominal cavity spans from the diaphragm to the bony pelvis.
• The pelvic cavity lies within the bony pelvis.
• The organs from several systems reside in the abdominopelvic cavities, including digestive, lymphatic, reproductive, and urinary systems

Homeostasis

• It is a way that physiological processes maintain balance and healthy functioning of the body.
• Disturbances in homeostasis can lead to disease or death if uncorrected.
• "Set points" or "normal/functioning ranges" do not indicate a static internal environment.
• The body's internal environment is dynamic, with feedback loops constantly engaged.

Feedback Loops

• Positive feedback loops are less common and reinforces the initial stimulus.
• Effector activity increases during positive feedback.
• These loops shut off when conditions return to the normal range.
• Negative feedback loops maintain homeostasis.
• When a regulated variable changes, a series of events occurs to return it to its normal value.
• Each regulated variable has a set point or baseline value.

Test your knowledge of fundamental concepts in anatomy and physiology. Topics include feedback loops, organ systems, tissue types, and anatomical terms. Questions cover bodily functions, organization levels, and system responsibilities.