bio 201 exam study guide

Levels of Structural Organization

Chemical → Cellular → Tissue → Organ → Organ System → Organism. Each level builds on the previous one, increasing in complexity.

Chemical Level

Atoms and molecules that form the building blocks of life.

Cellular Level

Cells are the smallest living units and perform specialized functions.

Tissue Level

Groups of similar cells working together to perform a common function.

Organ Level

Two or more tissue types working together to perform specific functions.

Organ System Level

Multiple organs working together to accomplish major body functions.

Organism Level

The complete living human composed of all organ systems.

Anatomy

Study of body structure.

Physiology

Study of body function.

Relationship Between Anatomy and Physiology

Structure determines function; anatomy makes physiology possible.

Homeostasis

Maintenance of a stable internal environment despite external changes.

Negative Feedback

Reverses a change to return the body to homeostasis. Most common feedback mechanism.

Example of Negative Feedback

Body temperature regulation and blood glucose regulation.

Positive Feedback

Amplifies a change until a specific event is completed.

Examples of Positive Feedback

Childbirth (oxytocin) and blood clotting.

Homeostatic Imbalance

Disruption of normal homeostasis that can result in disease.

Disease

Occurs when homeostatic mechanisms fail or become overwhelmed.

Anatomical Position

Standing upright, feet forward, arms at sides, palms facing forward.

Superior

Toward the head.

Inferior

Toward the feet.

Anterior (Ventral)

Toward the front of the body.

Posterior (Dorsal)

Toward the back of the body.

Medial

Toward the midline.

Lateral

Away from the midline.

Proximal

Closer to the point of attachment.

Distal

Farther from the point of attachment.

Superficial

Toward the body surface.

Deep

Away from the body surface.

Sagittal Plane

Divides body into right and left portions.

Midsagittal Plane

Divides body into equal right and left halves.

Frontal (Coronal) Plane

Divides body into anterior and posterior portions.

Transverse Plane

Divides body into superior and inferior portions.

Body Cavities

Cranial, vertebral, thoracic, abdominal, pelvic.

Dorsal Body Cavity

Cranial and vertebral cavities.

Ventral Body Cavity

Thoracic and abdominopelvic cavities.

Nine Abdominopelvic Regions

Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right iliac, hypogastric, left iliac.

Four Abdominopelvic Quadrants

RUQ, LUQ, RLQ, LLQ.

RUQ Organs

Liver, gallbladder, right kidney, part of pancreas, duodenum.

LUQ Organs

Stomach, spleen, left kidney, pancreas.

RLQ Organs

Appendix, cecum, right ovary.

LLQ Organs

Descending colon, sigmoid colon, left ovary.

Organ Systems

Integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive.

Integumentary System Function

Protection, temperature regulation, vitamin D production.

Skeletal System Function

Support, protection, movement, blood cell formation, mineral storage.

Muscular System Function

Movement, posture, heat production.

Nervous System Function

Rapid control and communication.

Endocrine System Function

Hormonal regulation.

Cardiovascular System Function

Transports oxygen, nutrients, hormones, and wastes.

Lymphatic System Function

Immunity and fluid balance.

Respiratory System Function

Gas exchange.

Digestive System Function

Breaks down food and absorbs nutrients.

Urinary System Function

Removes wastes and regulates water and electrolytes.

Reproductive System Function

Produces gametes and offspring.

Cell Theory

All living things are composed of cells; cells are the basic unit of life; new cells come from existing cells.

Plasma Membrane

Selectively permeable barrier controlling movement into and out of the cell.

Nucleus

Contains DNA and controls cell activities.

Nucleolus

Produces ribosomes.

Ribosomes

Site of protein synthesis.

Rough ER

Synthesizes proteins.

Smooth ER

Produces lipids and detoxifies substances.

Golgi Apparatus

Modifies, packages, and ships proteins.

Mitochondria

Produce ATP through cellular respiration.

Lysosomes

Digest worn-out organelles and pathogens.

Cytoplasm

Jelly-like fluid where organelles are suspended.

Simple Squamous Epithelium

Thin; diffusion and filtration; alveoli and capillaries.

Simple Cuboidal Epithelium

Secretion and absorption; kidney tubules and glands.

Simple Columnar Epithelium

Absorption and secretion; digestive tract.

Pseudostratified Columnar Epithelium

Secretes mucus; lines respiratory tract.

Stratified Squamous Epithelium

Protection; skin, mouth, esophagus.

Transitional Epithelium

Stretching; urinary bladder.

Functions of Epithelial Tissue

Protection, secretion, absorption, filtration.

Connective Tissue Functions

Support, protection, transport, energy storage.

Areolar Connective Tissue

Wraps organs and holds tissue fluid.

Adipose Tissue

Stores fat, cushions organs, insulates body.

Dense Regular Connective Tissue

Tendons and ligaments; withstands pulling force.

Dense Irregular Connective Tissue

Dermis; resists stress in many directions.

Hyaline Cartilage

Smooth support; nose, trachea, articular surfaces.

Elastic Cartilage

Flexible support; ear and epiglottis.

Fibrocartilage

Shock absorber; intervertebral discs and menisci.

Bone Tissue

Support, protection, mineral storage.

Blood

Transport tissue.

Nervous Tissue

Neurons transmit electrical impulses; neuroglia support neurons.

Skeletal Muscle

Voluntary, striated, attached to bones.

Cardiac Muscle

Involuntary, striated, heart only.

Smooth Muscle

Involuntary, nonstriated, hollow organs.

Cutaneous Membrane

Skin; dry membrane covering body surface.

Mucous Membrane

Lines body cavities open to exterior; secretes mucus.

Serous Membrane

Lines closed body cavities; secretes serous fluid.

Steps of Tissue Repair

Inflammation → Organization/Granulation → Regeneration or Fibrosis (Scar Formation).

Stem Cells

Undifferentiated cells capable of producing specialized cells.

Epidermis Layers (Deep to Superficial)

Stratum basale → spinosum → granulosum → lucidum (thick skin only) → corneum.

Dermis Layers

Papillary layer and reticular layer.

Melanin

Pigment protecting against UV radiation.

Sebaceous (Oil) Glands

Produce sebum to lubricate skin and hair.

Eccrine Sweat Glands

Produce watery sweat for cooling.

Apocrine Sweat Glands

Found in armpits and groin; active at puberty.

Hair Follicle

Produces hair.

Arrector Pili Muscle

Causes goosebumps.

Hair Function

Protection, sensation, heat retention.

Nail Function

Protects fingertips and aids gripping.