Anatomy and Physiology

Axial Skeleton

The part of the skeleton that includes the skull, spine, and rib cage, supporting the head and trunk.

Appendicular Skeleton

Includes the limbs (arms and legs) and the girdles (shoulder and pelvic bones) that connect them to the axial skeleton.

Ligament

Strong bands of tissue that connect bones to other bones.

Tendon

Connects muscles to bones.

Compact Bone

The hard, dense part of bone that provides strength.

Spongy Bone

Lighter bone found at the ends of bones, containing spaces.

Periosteum

A tough layer of tissue that covers the outside of bones.

Red Bone Marrow

Produces red blood cells, white blood cells, and platelets.

Yellow Bone Marrow

Stores fat and can convert to red marrow if needed.

Epiphysis

The end part of a long bone, which is usually wider than the shaft.

Diaphysis

The shaft or central part of a long bone.

Metaphysis

The region between the diaphysis and epiphysis; it contains growth plates.

Osteoarthritis

A type of arthritis where flexible tissue at the ends of bones wears down.

Osteoblasts

Cells that build new bone.

Osteoclasts

Cells that break down old bone.

X-rays

A type of imaging that shows the inside of the body, especially bones.

Ultrasound

Uses sound waves to create images of organs and tissues in the body.

MRI

A type of imaging that uses magnets and radio waves to see inside the body.

Rheumatoid Arthritis

An autoimmune disease that causes chronic inflammation in joints.

Infectious Arthritis

Joint inflammation caused by an infection.

Orbicularis Oculi

The muscle around the eyes that helps with blinking.

Orbicularis Oris

The muscle around the mouth that helps with speaking and eating.

Temporalis

A muscle on the side of the head that helps with chewing.

Smooth Muscle

Involuntary muscle found in organs like the stomach and blood vessels.

Skeletal Muscle

Muscle attached to bones, allowing voluntary movements.

Cardiac Muscle

The muscle of the heart, which pumps blood.

Contraction

When muscles shorten and produce movement.

Fibrocartilage

Tough tissue that provides support and absorbs shock in joints.

Sarcomere

The basic unit of a muscle that contracts.

Actin

A protein that forms thin filaments in muscle fibers.

Myosin

A protein that forms thick filaments in muscle fibers.

Type I Muscle Fibers

Slow-twitch fibers for endurance and long activities.

Type II Muscle Fibers

Fast-twitch fibers for quick, powerful movements.

Endomysium

A thin layer of tissue that wraps around each muscle fiber.

Perimysium

A layer of tissue that surrounds groups of muscle fibers.

Myofibril

A long, thread-like structure in muscle cells that helps with contraction.

Epimysium

A layer that covers the entire muscle.

Muscle Fatigue

The feeling of tiredness in muscles after intense activity.

Synovial Joints

Joints that allow for movement and contain fluid to reduce friction.

Articular (Hyaline) Cartilage

Smooth tissue at the ends of bones in joints.

Brain Stem

Controls basic life functions like breathing and heart rate.

Corpus Callosum

Connects the left and right sides of the brain.

Cerebellum

Coordinates movement and balance.

Cerebrum

The largest part of the brain, responsible for thinking and voluntary actions.

Frontal Lobe

Responsible for decision-making and planning.

PNS (Peripheral Nervous System)

The part of the nervous system outside the brain and spinal cord.

Cerebrospinal Fluid (CSF)

Fluid that surrounds and protects the brain and spinal cord.

Reflex Arc

The pathway that controls a reflex action.

CNS (Central Nervous System)

The brain and spinal cord.

Medulla Oblongata

Controls automatic functions like breathing and heart rate.

Occipital Lobe

Responsible for visual processing.

Parietal Lobe

Processes sensory information like touch and pain.

Diencephalon

Contains the thalamus and hypothalamus, involved in sensory and hormonal regulation.

Spinal Cord

Sends signals between the brain and the body.

Temporal Lobe

Involved in hearing and memory.

Glial Cells

Support cells in the nervous system.

Nodes of Ranvier

Gaps in the myelin sheath that help speed up nerve impulses.

Myelin Sheath

A protective covering around nerve fibers that helps transmit signals faster.

Axon

The long part of a neuron that carries signals away from the cell body.

Dendrite

The part of a neuron that receives signals from other neurons.

Sensory Neuron

Carries signals from sensory receptors to the brain.

Motor Neuron

Sends signals from the brain to muscles.

Interneurons

Connect neurons within the brain and spinal cord.

Neurotransmitters

Chemicals that transmit signals between neurons.

Synapse

The space between two neurons where signals are transmitted.

Action Potential

The electrical signal that travels along a neuron.

Sodium-Potassium Pump

A mechanism that helps maintain the electrical charge in neurons.

Receptors

Proteins that receive signals from neurotransmitters.

Refractory Period

The time after a neuron fires when it cannot fire again.

Threshold Stimulus

The level of stimulus needed to trigger an action potential in a neuron.

Thyroxine

A hormone that regulates metabolism.

Insulin

A hormone that helps control blood sugar levels.

Glucagon

Raises blood sugar levels, working with insulin.

Epinephrine

Also known as adrenaline, it prepares the body for fight or flight.

Testosterone

A hormone involved in male development and reproduction.

Estrogen

A hormone involved in female development and reproduction.

Growth Hormone (GH)

Stimulates growth and cell reproduction.

Pancreas

An organ that produces insulin and glucagon.

Pituitary Gland

The 'master gland' that controls other endocrine glands.

Testes

Male reproductive glands that produce sperm and hormones.

Ovaries

Female reproductive glands that produce eggs and hormones.

Adrenal Glands

Produce hormones that help regulate metabolism and stress.

Hypothalamus

Controls the pituitary gland and regulates many body functions.

Pineal Gland

Produces melatonin, which regulates sleep.

Thyroid Gland

Produces hormones that regulate metabolism.

Parathyroid Glands

Regulate calcium levels in the body.

Thymus Gland

Involved in immune function, particularly in childhood.

Type I Diabetes

A condition where the body does not produce insulin.

Type II Diabetes

A condition where the body does not use insulin properly.

Glycogen

A stored form of glucose in the liver and muscles.