chapter 6: Anatomy, Physiology, and Pathophysiology for the EMT

Flashcards covering human anatomy, physiology, and pathophysiology based on EMT lecture notes, including skeletal, respiratory, circulatory, nervous, and digestive systems.

Anatomy

A field of study that focuses on the physical structure of the body and its systems.

Physiology

The study of the normal functions and activities of biologic components within the body.

Pathophysiology

The study of functional changes that accompany a particular disease or syndrome.

Topographic Anatomy

The body's surface landmarks and structures that guide clinicians to the locations of internal features.

Anatomic Position

A frame of reference where the patient stands facing the clinician with palms and toes facing forward.

Coronal (frontal) plane

A vertical plane that runs through the body and divides it into front and back sections.

Sagittal (lateral) plane

A vertical plane that divides the body into left and right sections.

Midsagittal (midline) plane

A subtype of the sagittal plane that divides the body into equal left and right halves.

Transverse (axial) plane

A horizontal plane that divides the body into top and bottom sections.

Axial Skeleton

The part of the skeleton that forms the longitudinal axis of the body, including the skull, facial bones, thoracic cage, and vertebral column.

Appendicular Skeleton

The part of the skeleton comprising the upper and lower extremities and the points where they connect to the axial skeleton.

Ligaments

Fibrous tissues that connect bone to bone and help stabilize joints.

Cartilage

Semirigid yet flexible tissue that covers and cushions the ends of articulating bones.

Tendons

Tissues that attach muscle to bone.

Joint Capsule

A fibrous sac composed of connective tissue that holds the bone ends of most joints together.

Articular Cartilage

A thin, pearly white layer of cartilage on the ends of bones that allows them to glide easily within a joint.

Synovial Membrane

Special tissue on the inner lining of the joint capsule responsible for making synovial fluid.

Ball-and-socket joints

Joints like the shoulder and hip that allow rotation and bending.

Hinge joints

Joints like the finger, elbow, and knee with motion restricted to flexion and extension.

Foramen Magnum

A large opening at the base of the cranium serving as a passageway for the spinal cord to connect with the brain.

Maxillae

The bones that form the upper jaw.

Mandible

The bone that forms the lower jaw.

Zygomas

The bones of the cheeks.

Cervical spine

The first seven vertebrae ($C1$ through $C7$) located in the neck.

Thoracic spine

The $12$ vertebrae to which the ribs are attached.

Lumbar spine

The five vertebrae located below the thoracic spine.

Sacrum

Five fused vertebrae that join the iliac bones of the pelvis at the sacroiliac joints.

Coccyx

The last four fused vertebrae of the spinal column, commonly referred to as the tailbone.

Sternum

The breastbone, consisting of the manubrium, the body, and the xiphoid process.

Xiphoid process

The narrow, cartilaginous structure at the inferior tip of the sternum.

Humerus

The single bone of the upper arm.

Radius

The forearm bone located on the lateral, or thumb, side.

Ulna

The forearm bone located on the medial, or little finger, side.

Carpals

The eight bones that form the wrist.

Metacarpals

The five bones that form the palm of the hand.

Phalanges

The bones of the fingers or toes.

Coxae

The two large hip bones formed by the fusion of the ilium, ischium, and pubis.

Acetabulum

The hip joint where the pelvis articulates with the femoral head.

Greater trochanter

A projection on the lateral side of the femur, proximal to the femoral head and neck, serving as a muscle anchor point.

Tibia

The larger of the two lower leg bones, also known as the shinbone, positioned on the medial side.

Fibula

The smaller of the two lower leg bones, positioned on the lateral side.

Calcaneus

The heel bone.

Striated (skeletal) muscle

Voluntary muscle that attaches to the skeleton and is under conscious control.

Smooth muscle

Involuntary muscle found within blood vessels and the intestines.

Cardiac muscle

Unique involuntary muscle that can generate its own electrical impulses and requires a continuous supply of oxygen.

Homeostasis

The body's self-regulating process for preserving internal balance or equilibrium in order to survive.

Fontanelles

Soft spots on an infant's head where the sutures have not yet fused.

Nasopharynx

The upper section of the pharynx that connects with the nasal cavity above the soft palate.

Epiglottis

A thin, leaf-shaped flap that covers the larynx during swallowing to keep food and liquid out of the trachea.

Trachea

A semirigid air tube approximately $5\,\text{inches}$ ($13\,\text{cm}$) long made of C-shaped rings of cartilage.

Alveoli

Tiny grapelike clusters of air sacs where oxygen and carbon dioxide are exchanged.

Pleura

Smooth, glistening tissue that covers the lungs (visceral) and lines the inside of the chest cavity (parietal).

Diaphragm

The primary muscle of breathing, a dome-shaped structure that divides the thorax from the abdomen.

Negative-pressure breathing

The process where air is sucked into the lungs as the chest cavity enlarges and pressure falls.

Ventilation

The movement of air between the lungs and the environment.

Respiration

The process of gas exchange at the cellular level.

Diffusion

A passive process in which molecules move from an area of higher concentration to an area of lower concentration.

Medulla oblongata

A portion of the brainstem sensitive to $pH$ changes that stimulates the phrenic nerve to control breathing.

Hypoxic Drive

A backup system to control respiration that stimulates breathing when oxygen levels fall.

Tidal Volume

The amount of air moved into or out of the lungs during a single breath, generally $500\,\text{mL}$ in an adult.

Minute Volume

The amount of air that moves in and out of the lungs in $1\,\text{minute}$, calculated as $Respiratory\,rate \times Tidal\,volume$.

Systole

The phase of the cardiac cycle when the left ventricle contracts and pumps blood into the aorta.

Stroke Volume ($SV$)

The amount of blood moved in one beat, typically $70$ to $80\,\text{mL}$ in an adult.

Cardiac Output ($CO$)

The amount of blood moved in $1\,\text{minute}$, calculated as $CO = HR \times SV$.

Sinoatrial node

The area high in the atria where the normal electrical impulse for the heart begins.

Tunica media

The middle layer of an artery, formed from smooth muscles that can contract and dilate.

Systemic Vascular Resistance ($SVR$)

The resistance to blood flow within all blood vessels except the pulmonary vessels.

Erythrocytes

Red blood cells containing hemoglobin, which is responsible for carrying oxygen.

Leukocytes

White blood cells that play an important role in the body's immune defense against infection.

Platelets

Tiny elements essential in the initial formation of a blood clot to stop bleeding.

Plasma

The liquid portion of the blood, composed of $92\%$ water and $7\%$ proteins like albumin.

Perfusion

The circulation of blood in an organ or tissue to meet metabolic needs.

Shock (hypoperfusion)

A state of systemic inadequate perfusion where the entire body is not receiving enough oxygenated blood.

Hydrostatic pressure

The force that occurs as fluid pushes against vessel walls to force fluid out of the capillary.

Oncotic pressure

The opposing force to hydrostatic pressure, where proteins pull water into the capillary by diffusion.

Alpha-adrenergic receptors

Receptors found in blood vessels that cause constriction and increased blood pressure when stimulated.

Beta-1 receptors

Receptors found in the heart that increase heart rate and force of contraction when stimulated.

Beta-2 receptors

Receptors found in the lungs that cause bronchodilation when stimulated.

Central Nervous System ($CNS$)

The portion of the nervous system comprising the brain and spinal cord.

Cerebrum

The largest portion of the brain, responsible for higher functions such as reasoning, learning, and managing emotions.

Cerebellum

The subdivision of the brain that controls balance, muscle coordination, and posture.

Brainstem

The primitive part of the $CNS$ comprising the midbrain, pons, and medulla oblongata, controlling involuntary life-sustaining functions.

Cerebrospinal Fluid ($CSF$)

A colorless fluid around the brain and spinal cord that cushions structures, filters out toxins, and maintains balanced acidity.

Somatic Nervous System

The portion of the peripheral nervous system regulating voluntary activities like walking and talking.

Autonomic Nervous System

The portion of the peripheral nervous system controlling involuntary actions like digestion and heart rate.

Sympathetic Nervous System

The division of the autonomic nervous system responsible for the 'fight-or-flight' reaction.

Parasympathetic Nervous System

The division of the autonomic nervous system that slows body activities or returns the body to its resting state.

Germinal layer

The innermost layer of the epidermis that continuously produces new skin cells and pigment granules.

Stratum corneum

The outermost exposed surface layer of the epidermis consisting of dead cells.

Sebaceous glands

Glands that secrete an oily substance called sebum to waterproof the skin.

Subcutaneous tissue

The layer beneath the dermis composed largely of fat, serving as an insulator and energy reservoir.

Retroperitoneal organs

Organs that lie behind the abdominal cavity, such as the kidneys and pancreas.

Islets of Langerhans

The endocrine portion of the pancreas where insulin and glucagon are produced.

Bile

A green-black substance produced by the liver and stored in the gallbladder to assist in fat digestion.

Cecum

The first portion of the large intestine into which the small intestine (ileum) opens.

pH

A measure of acidity or alkalinity in a solution, with the human body's normal range being $7.35$ to $7.45$.

Aerobic Metabolism

The process of using oxygen to turn nutrients into energy ($ATP$), yielding carbon dioxide and water as waste.

Anaerobic Metabolism

The process of creating energy ($ATP$) without oxygen, resulting in the production of lactic acid.

Hypoxia

A decreased level of oxygen in the body.

Hypercapnia

An elevated level of carbon dioxide in the body.