Test 2 Anatomy and phisiology

Skeletal System

Composed of 206 bones and provides support, protection, and movement.

Support

The function of the skeletal system that supports internal tissues and organs.

Protection

A function of the skeletal system where it forms a cage-like structure to protect internal organs.

Bone

A highly specialized connective tissue whose matrix is hard and calcified.

Cartilage

A specialized connective tissue that has the consistency of firm plastic or gristle-like gel.

Ligaments

A band of white fibrous tissue that connects bones.

Compact Bone

The outer layer of bone, hard and dense, which looks smooth.

Spongy Bone

Porous bone located at the ends of long bones, filled with marrow and contains needlelike projections called trabeculae.

Hematopoiesis

The process of blood cell formation in red bone marrow.

Long Bones

Bones classified by shape, exemplified by the humerus in the upper arm.

Short Bones

Bones classified by shape, exemplified by carpals in the wrist.

Flat Bones

Bones classified by shape, exemplified by the frontal bone in the skull.

Irregular Bones

Bones classified by shape, exemplified by vertebrae in the spinal cord.

Compact Bone

Bone that has no open spaces and contains structural units called osteons.

Osteon

The structural unit of compact bone, also known as the Haversian system.

Trabeculae

Needle-like threads of bone found in spongy bone that create a textured structure surrounded by open spaces.

Red Bone Marrow

Substance found in the spaces of spongy bone, involved in the production of blood cells.

Chondrocyte

A type of cell located in lacunae that forms cartilage.

Lacunae

Small spaces within the cartilage matrix where chondrocytes are located.

Osteoblasts

Bone-forming cells that produce osteocytes and are involved in the replacement of cartilage with bone.

Osteoclasts

Bone-resorbing cells that work alongside osteoblasts to sculpt bones into their adult shape.

Matrix (in cartilage)

A gel-like substance that lacks blood vessels and contains chondrocytes.

Epiphyses

The ends of long bones where spongy bone is typically found.

Long Bones

Contribute to height and length in areas such as toes, fingers, and arms (e.g., femur in the leg).

Short Bones

Occur in clusters, allowing a wide range of movement, as seen in the ankles and wrists.

Flat Bones

Provide structural contour and protection.

Irregular Bones

Accommodate other structures; includes the sesamoid category (e.g., patella).

Periosteum

Strong membrane covering the bone except at joint surfaces.

Endosteum

Lines the medullary cavity in bones.

Medullary Cavity

Contains yellow marrow, located within the diaphysis of long bones.

Diaphysis

The shaft of a long bone, composed of compact bone and shaped like a hollow tube.

Epiphysis

Ends of long bones, composed of spongy bone and containing red bone marrow.

Articular Cartilage

Thin external covering of cartilage on each epiphysis for attachments and cushioning the joint.

Body Membranes

Thin, soft sheets of tissue that cover, line, lubricate and anchor parts.

Epithelial Membranes

Membranes that lubricate & protect the body against infection, including cutaneous, serous, and mucous types.

Cutaneous Membrane

Also known as skin, it is the primary organ of the integumentary system.

Serous Membrane

Lines cavities that do not open to the outside; secretes fluid to prevent friction.

Mucous Membrane

Lines body cavities that open to the outside and secretes mucus for lubrication and protection.

Connective Tissue Membranes

Do not contain epithelial components; includes synovial membranes that secrete synovial fluid.

Integumentary System Functions

Includes protection, temperature regulation, sense organ activity, excretion, and synthesis of Vitamin D.

Protection

First line of defense against infection and injury, making the skin resistant to bacteria and fungi.

Temperature Regulation

Involves blood vessel constriction and dilation, along with sweat gland activity to maintain body temperature.

Dermis

Deeper layer of skin, well supplied with blood vessels, nerves, glands, and hair follicles.

Keratin

A protein that makes the stratum corneum waterproof and tough.

Melanocytes

Specialized cells in the epidermis that produce melanin, responsible for skin color.

Dermal Papillae

Small projections in the upper layer of the dermis that supply capillaries to the epidermis and form fingerprints.

Subcutaneous Layer

Connects the skin to muscles, composed of adipose and loose connective tissue, providing insulation and cushioning.

Sudoriferous Glands

Sweat glands located in the dermis and subcutaneous layers that secrete perspiration.

Sebaceous Glands

Oil glands that lubricate skin and hair, and inhibit bacterial growth.

Aging Effects on Skin

Includes dryness, thinning, loss of elasticity, pigmentation changes, and hair thinning.

Nervous System

System that transmits information by means of nerve impulses and reflex arcs.

Neuron

Nerve cell that consists of a cell body, dendrites, and an axon.

Cerebrospinal Fluid (CSF)

Fluid that cushions the brain and spinal cord, formed in the choroid plexus.

Reflex Arc

Pathway by which nerve impulses are conducted from receptors to effectors.

Central Nervous System (CNS)

Consists of the brain and spinal cord and functions like a complex computer.

Peripheral Nervous System (PNS)

Nerves that connect the CNS to the rest of the body.

Glia (neuroglia)

Support cells that structurally and functionally support neurons.

Myelin

White fatty substance produced by Schwann cells surrounding axons to speed impulse transmission.

Synapse

The gap between the axon terminal of one neuron and the dendrite of another where neurotransmitters are released.

Neurotransmitter

Chemical compounds that transmit signals across a synapse.

Sensory Neurons

Conduct impulses to the spinal cord and brain.

Motor Neurons

Conduct impulses away from the brain and spinal cord to muscles and glands.

Interneurons

Conduct impulses between sensory and motor neurons.

Thalamus

Part of the Diencephalon that relays sensory impulses to the cerebral cortex.

Hypothalamus

Regulates autonomic nervous system functions, controls hormone secretion, and maintains homeostasis.

Cerebellum

Part of the CNS that coordinates muscle contractions and maintains balance.

Cerebrum

Largest part of the brain responsible for higher brain functions, divided into lobes.

Dura Mater

Outermost protective layer of the meninges surrounding the brain and spinal cord.

Arachnoid Mater

Middle layer of the meninges, resembling a spider web.

Pia Mater

Innermost layer of the meninges that provides nutrients to nervous tissue.

Muscle Contraction

The process by which muscle fibers shorten and produce movement.

Skeletal Muscle

Also known as striated or voluntary muscle, it makes up 40% to 50% of body weight and is under voluntary control.

Cardiac Muscle

Muscle that composes the bulk of the heart, characterized by striations and intercalated disks.

Smooth Muscle

Also called nonstriated or involuntary muscle, it lacks striations and is found in walls of hollow visceral structures.

Prime Mover

A muscle whose contraction is primarily responsible for producing a given movement.

Synergist

Muscles that assist the prime mover in producing a given movement.

Antagonist

Muscle that opposes the action of the prime mover, relaxing during movement.

Tonic Contraction

A specialized muscle contraction that maintains posture without producing movement.

Heat Production

The process by which muscle contraction produces heat to maintain body temperature.

Threshold Stimulus

The minimal level of stimulation required to cause a muscle fiber to contract.

Motor Unit

The combination of a motor neuron and the muscle cell(s) it innervates.

Lactic Acid

A byproduct produced in the absence of adequate oxygen during muscle contraction, contributing to muscle soreness.

ATP (Adenosine Triphosphate)

The energy carrier that muscle cells use for contractions.

Flexion

Movement that decreases the angle between two bones at their joint.

Extension

Movement that increases the angle between two bones at their joint.

Abduction

Movement of a part away from the midline of the body.

Adduction

Movement of a part toward the midline of the body.

Muscle Fatigue

A condition resulting in reduced strength of muscle contraction due to repeated stimulation without rest.

Inversion

Movement that turns the bottom of the foot toward the midline.

Eversion

Movement that turns the bottom of the foot outward, away from the midline.

Ligament

Fibrous connective tissue that attaches bone to bone, stabilizing joints.

Tendon

Fibrous connective tissue that attaches muscle to bone.

Body Membranes

Thin, soft sheets of tissue that cover, line, lubricate and anchor parts.

Epithelial Membranes

Membranes that lubricate & protect the body against infection, including cutaneous, serous, and mucous types.

Cutaneous Membrane

Also known as skin, it is the primary organ of the integumentary system.

Serous Membrane

Lines cavities that do not open to the outside; secretes fluid to prevent friction.

Mucous Membrane

Lines body cavities that open to the outside and secretes mucus for lubrication and protection.

Connective Tissue Membranes

Do not contain epithelial components; includes synovial membranes that secrete synovial fluid.

Integumentary System Functions

Includes protection, temperature regulation, sense organ activity, excretion, and synthesis of Vitamin D.

Protection

First line of defense against infection and injury, making the skin resistant to bacteria and fungi.