BIO 168 Anatomy & Physiology - Midterm Review (Ch 1-8)

Vocabulary flashcards covering major terms from Chapters 1-8 of BIO 168.

Anatomical position

Standard reference position: standing, feet together, arms at sides, palms facing forward.

Levels of organization (from least to most complex)

Chemical, cellular, tissue, organ, organ system, organism.

Homeostasis

Stable internal environment maintained by regulatory mechanisms.

Receptor (sensor)

Detects environmental changes; part of homeostatic regulation.

Control center (integration center)

Processes receptor information and issues commands.

Effector

Responds to commands to oppose the stimulus.

Homeostatic regulation pathway

Physiological adjustment to preserve homeostasis in variable environments.

Frontal (coronal) plane

Divides the body into anterior and posterior portions.

Sagittal plane

Divides the body into right and left portions; midsagittal vs parasagittal describe exact positioning.

Transverse (horizontal) plane

Divides the body into superior and inferior portions.

Thoracic cavity

Cavity containing the pleural cavities and mediastinum; houses the heart and lungs.

Pleural cavity

Lined by pleura and contains a lung.

Mediastinum

Contains connective tissue and the pericardial cavity with the heart.

Abdominopelvic quadrants

Four quadrants formed by perpendicular planes for describing locations of pain or injury.

Abdominopelvic nine regions

Nine regions used to describe precise organ locations within the abdomen and pelvis.

Superior

Toward the head or upper part of a structure.

Inferior

Toward the feet or lower part of a structure.

Anterior (ventral)

Toward the front of the body.

Posterior (dorsal)

Toward the back of the body.

Medial

Toward the midline of the body.

Lateral

Away from the midline.

Proximal

Nearer to the point of attachment or to a given reference point.

Distal

Farther from the point of attachment or from a reference point.

Cephalic (cranial)

Toward the head.

Caudal

Toward the tail; in humans, toward the feet.

Epithelial tissue

Covers surfaces, lines cavities, forms glands; avascular and highly regenerative.

Connective tissue

Fills internal spaces, provides structural support, and stores energy.

Muscle tissue

Specialized for contraction to produce movement.

Neural tissue

Conducts electrical impulses to carry information.

Gland

Secretory organ derived from epithelia; endocrine or exocrine.

Endocrine gland

Secretes hormones into interstitial fluid and bloodstream.

Exocrine gland

Secretes onto epithelial surfaces or into ducts.

Keratinocytes

Primary cell type of the epidermis.

Stratum basale (germinativum)

Deepest epidermal layer; contains basal cells and Merkel cells; site of cell division.

Stratum spinosum

8–10 keratinocyte layers; desmosomes; contains Langerhans cells.

Stratum granulosum

3–5 keratinocyte layers; keratinization begins; cells flatten and membranes thicken.

Stratum lucidum

Clear layer found only in thick skin; lies between granulosum and corneum.

Stratum corneum

Outer protective layer of dead, keratinized cells; 15–30 layers.

Dermis

Middle skin layer with papillary and reticular layers; contains vessels, nerves, and glands.

Hypodermis (subcutaneous layer)

Not part of skin; mostly adipose tissue; energy storage.

Tension (cleavage) lines

Orientation of collagen/elastic fibers in skin; guides surgical incisions.

Burn depth: first-degree

Affects only epidermis; erythema and pain (e.g., sunburn).

Burn depth: second-degree

Affects epidermis and part of dermis; blistering and pain.

Burn depth: third-degree

Full-thickness burn; epidermis and dermis destroyed; grafting often required.

Sebaceous glands

Holocrine glands that secrete sebum to lubricate hair and skin; antimicrobial.

Sweat glands (sudoriferous glands)

Produce sweat; two types: apocrine and merocrine.

Apocrine glands

Found in axillae, around nipples, and in pubic region; secretions influenced by hormones and can be odorous.

Merocrine (eccrine) glands

Sweat glands that secrete directly onto the skin surface for thermoregulation.

Hair follicle

Structure that produces hair; associated with arrector pili and sebaceous gland.

Hair matrix

Region of active cell division at the base of the hair follicle.

Hair growth cycle

Active growth phase followed by resting phase; cycle length varies by region and individual.

Nail matrix

Growth area of the nail from which nail substance is produced.

Melanin

Pigment produced by melanocytes in the epidermis; determines skin color.

Carotene

Orange-yellow pigment from diet contributing to skin coloration.

Basement membrane

Anchor between epidermis and dermis; via hemidesmosomes.

Osteoblast

Bone-forming cell; differentiates into osteocytes.

Osteocyte

Mature bone cell; maintains bone matrix.

Osteoclast

Bone-resorbing cell; activity promoted by PTH.

Osteoid

Unmineralized bone matrix laid down by osteoblasts.

Haversian (central) canal

Central canal of an osteon containing blood vessels.

Canaliculi

Small channels connecting lacunae in bone tissue.

Nutrient foramen

Opening that allows blood vessels to enter bone marrow.

Endochondral ossification

Bone formed from a cartilage model; lengthwise growth occurs at epiphyseal plate.

Intramembranous ossification

Bone forms directly from mesenchyme without cartilage model.

Periosteum

Outer fibrous layer and inner cellular layer surrounding bone; growth and repair.

Endosteum

Lining of the medullary cavity; active in growth and remodeling.

Parathyroid hormone (PTH)

Rises blood calcium by stimulating osteoclasts and enhancing intestinal calcium absorption via calcitriol.

Calcitonin

Lowers blood calcium by inhibiting osteoclasts; released when calcium is high.

Calcitriol

Active vitamin D; increases intestinal calcium absorption and renal calcium reabsorption.

RANKL

Osteoblast-derived signal that stimulates osteoclast differentiation and activity.

Transverse fracture

Fracture across the shaft of a long bone.

Spiral fracture

Fracture caused by twisting stresses along the length of a bone.

Displaced fracture

Fracture where bone ends are out of normal alignment.

Nondisplaced fracture

Fracture where bone remains in proper alignment.

Compression fracture

Crush injury to vertebrae; common with osteoporosis.

Greenstick fracture

Partial fracture in which one side of the bone breaks and the other bends; common in children.

Comminuted fracture

Fracture producing multiple bone fragments.

Epiphyseal fracture

Fracture through the growing epiphyseal plate; can affect growth.

Pott’s fracture

Fracture of the ankle involving malleoli.

Colles fracture

Distal radius fracture near the wrist.

Atlas (C1)

First cervical vertebra; supports the head; permits nodding.

Axis (C2)

Second cervical vertebra; contains the dens for rotational head movement.

Vertebral column curvatures (primary vs secondary)

Primary curves (thoracic, sacral) present at birth; secondary curves (cervical, lumbar) develop after birth.

Pelvis components

Ilium, ischium, and pubis; sacrum; acetabulum.

Glenohumeral joint

Shoulder joint; ball-and-socket type with wide range of motion.

Hinge joints (elbow)

Joints that permit bending and straightening; stable due to bones, capsule, and ligaments.

Fibrous joints

Immovable joints such as sutures and gomphosis; structural type.

Cartilaginous joints

Joint held together by cartilage (e.g., synchondrosis); limited mobility.

Synovial joints

Freely movable joints with a synovial cavity, capsule, and ligaments.

Flexion

Decreases the angle of a joint.

Extension

Increases the angle of a joint; can become hyperextension when past neutral.

Abduction

Movement away from the midline in the frontal plane.

Adduction

Movement toward the midline in the frontal plane.

Circumduction

Movement in which the distal end traces a circle while the proximal end stays fixed.

Pronation

Forearm rotation that turns the palm downward.

Supination

Forearm rotation that turns the palm upward.

Opposition

Thumb movement toward the surface of the palm or other fingers for grasping.

Inversion

Twisting of the sole inward.

Eversion

Twisting of the sole outward.

Protraction

Anterior movement of a body part in the horizontal plane.