Anatomy & Physiology Ch. 1-3

Anatomy

Study of structures and relationships between structures of the human body

Physiology

Functions of specific organ systems/cellular/molecular events; how all elements carry out processes necessary for life

Complementarity

Function is dependent on structure; form of a structure relates to its function

Levels of Structural Organization

Atoms, molecules, organelles, cells, tissues, organs, organ systems

Integumentary, Skeletal, Muscular

Protection, support, movement

Endocrine, Nervous

Communication, integration

Lymphatic, Immune

Defense, assimilation

Respiratory, Cardiovascular

Gas exchange

Circulatory (Cardiovascular, Lymphatic)

Transport

Excretory (Digestive, Respiratory, Urinary)

Absorption, excretion

Male & Female Reproductive

Reproduction

Anatomical Position

Body is erect, palms face forward, thumbs point away from the body

Cavity

Open spaced within the body closed to the outside containing the internal organs

Dorsal Body Cavity

Dorsal nervous system, lined with meninges

Cranial Cavity

Contains brain, formed by the skull

Vertebral/Spinal Cavity

Contains spinal cord, formed by vertebral column

Ventral Cavity

Anterior to dorsal cavity, houses viscera, lined with serous membranes

Thoracic Cavity

Above diaphragm, contains pleura and mediastinum

Pleura

Covers lungs

Mediastinum

Between pleura, contains heart & thymus

Pericardium

Houses heart

Abdominopelvic Cavity

Below diaphragm with arbitrary boundary (no tissue), lined with peritoneum

Abdominal

Digestive organs

Pelvic

Bladder, rectum, & some reproductive organs

Diaphragm

Large, dome-shaped muscle, separates thoracic and abdominopelvic cavities

Serous Membranes (Serosae)

Parietal, Visceral, Fibrous

Parietal Serosa

Lines the body cavity walls, superficial

Visceral Serosa

Covers the outer surfaces of organs, deep

Fibrous Serosa

Unique to the heart, most superficial, toughest

Serous Membranes Functions

Secrete/separated by a thin layer of serous fluid, found in the serous cavity

Sagittal

Divides the body/organ into left/right

Midsagittal

Equal halves

Parasagittal

Unequal halves

Frontal/Coronal

Divides body/organ into front/back

Transverse/Horizontal

Divides body/organ into top/bottom

Oblique

Runs diagonally between vertical/horizontal plane

Characteristics of Living Organisms

Maintaining boundaries, movement, responsiveness, digestion, metabolism, excretion, reproduction, and growth

Maintaining Boundaries

Cell membrane, maintains separate internal & external environments, separates chemical reactions, prevents loss of cellular contents

Movement

Travel of organism & transport of molecules, osmosis and pumps

Responsiveness

Ability to detect changes in internal/external environments & respond, irritability, excitability, & communication

Digestion

Breaking down food into simpler molecules & absorbing useful components

Metabolism

Sum of all chemical reactions

Excretion

Removal of wastes

Cellular Reproduction

Mitosis creates identical copies

Organismal Reproduction

Meiosis creates genetic variety through sperm & egg in fertilization

Growth

Increase in size

Viruses

Genome surrounded by a protective protein coat, some capable of locomotion, intracellular parasite, needs host to allow reproduction

Virus Characteristics of Life

Mutation, no growth, homeostasis, or metabolism

Cells

Grow, maintain homeostasis, metabolism, mutation, DNA, reproduce independently by cell division

Nutrients

Fuel energy needs for functions/cell building

Oxygen

Required for cell respiration that facilitates energy release from food

Water

Most prevalent substance in the body, provides an environment for chemical reactions & medium for secretions/excretions

Normal Body Temp

37* C; required for chemical reactions to occur at a proper rate

Atmospheric Pressure

Appropriate range for proper gas exchange to occur

Homeostasis

Ability to maintain internal conditions when eternal conditions change

Dynamic Equilibrium

Internal conditions are maintained within a narrow range, rather than a specific value

Variable/Stimulus

Required factor/component

Receptor

Unit that monitors stimuli & communicates to control center

Afferent Pathway

Flow of information towards control center

Control Center

Structure that determines range of acceptability, analyzes input, coordinates response by effector, & turns on/off homeostatic mechanisms

Efferent Pathway

Flow of information from control center

Effector

Unit that carries out mechanism dictated by control center to return body to homeostasis

Response

Correction of stimulus

Negative Feedback Systems

Prevention of sudden, severe changes in the body, returns to normal homeostatic range

Negative Feedback Organ Systems

Nervous & Endocrine

Negative Feedback System Examples

Body temperature, blood glucose, O2/CO2 balance, blood pressure

Positive Feedback Systems

Effectors work in same direction as the original stimulus & results in a greater deviation from the set point

Positive Feedback Examples

Immune response, lactation, blood clotting, labor contractions

Homeostatic Imbalances

Leads to disease and/or death because compensation is not possible

Aging & Homeostasis

“+” occurs more often, “-” occurs less often

Blood Pressure

Force of blood on walls of vessels

Blood Clotting

Damage to blood vessel wall, platelets adhere to damaged site, clot grows until tear is plugged

Elements

Fundamental unit of matter

96% of body mass elements

C, H, O, N

Molecule

Two or more atoms held together by chemical bonds

Compound

Two or more different elements combine & are held together by chemical bonds

Mixture

Substances composed of two or more components mixed physically with no chemical bonding between molecules

Solution

Particles are tiny, do not settle out, or scatter light

Colloid

Solute particles are larger than in a solution, scatter light, and do not settle out

Suspension

Solute particles are very large, settle out, and may scatter light

Energy

Capacity to do work or cause change

Kinetic Energy

Energy in motion

Potential Energy

Stored Energy

Chemical Bonds

Energy relationship linking the electrons of reacting atoms

Ionic

Atoms transfer 1 or more electrons

Covalent

Electrons are shared

Hydrogen Bonds

Special bonds with N, F, or O

Ionic Characteristics

Charge holds to atoms together, exist as solid crystals, dissolve into ions when in water

Anions

Electron acceptor, with net negative charge that have picked up one or more electrons

Cations

Electron donor with net positive charge that have given up one or more electron

Crystals

Cations & Anions held together by ionic bonds; dissolves into ions when put into water

Non-polar

Electrically neutral as a molecule

Polar

Has a positive and negative side

Intramolecular Bonds

Hydrogen bonding between different atoms of the same, large molecule

Surface Tension

Caused by hydrogen bonding between many water molecules

Chemical Reactions

Results when bonds are formed, rearranged, or broken

Metabolism

Sum of all chemical reactions in the body

Anabolic Reactions

Joining of two or more atoms to form larger, more complex molecules, endothermic, dehydration synthesis

Catabolic Reactions

Breakdown of a molecule into two or more smaller molecules, exothermic, decomposition reaction

Biochemistry

Study of chemical composition and recreations of living matter