Human Anatomy and Physiology Lecture Exam 1

Gross Anatomy

structures that are visible to to the naked eye (ex. liver, eyes)

Microscopic Anatomy

structures that are too small to view with the naked eye (cells, molecules)

Dynamic Steady State

things are constantly changing and must actively compensate to maintain homeostasis

Stimulus

changes in a variable that is regulated (ex. temperature, baby suckling on nipple)

Receptor

structure that detects the stimulus, sends out input information to the control center

Afferent Pathway

first pathway in homeostasis (from the receptor to the control center)

Control Center

integrates input and initiates change through the effector (usually the brain or endocrine gland)

Efferent Pathway

2nd pathway in homeostasis, initiates effect

Effector

structure (muscle or gland) that brings about change to the stimulus

Response

homeostasis restored (ex. oxytocin release when baby suckles)

Negative Feedback Loop

keeps internal environment stable, always occuring, restores balance, inhibits stimulus

Positive Feedback Loop

prolongs stimuli and enhances response

Atoms

smallest building blocks of life

Elements

smallest units of matter with individual properties (ex. periodic table of elements)

Macromolecules of Life

DNA, RNA, Proteins, Carbohydrates, Lipids, Nucleic Acids

Major Elements

Carbon, Hydrogen, Oxygen, Nitrogen, (building blocks for all macromolecules)

Oxygen

necessary for ATP generation and cellular respiration (converting nutrients into energy)

Calcium & Phosphorus

Important roles in bone formation and homeostasis

Lesser Elements

Potassium, Sodium, Chlorine (present in electrically excitable cells (cells that have action potential like neurons and muscles))

Inorganic Molecules

Molecules with no carbon

Organic Molecules

molecules with 1 or multiple carbon

ionic bond

between oppositely charged elements + -

covalent bond

highly stable bonds (strongest bond), electrons are shared across elements

hydrogen bonds

weak bonds

Polarity

distribution of charge across a molecule (polar = unequal charge distribution)

electro-attractive forces

when 2 molecules are pulled together because they are oppositely charged allow hydrogen bond formation

Cohesion

the association of water molecules (how they stick together through bonds) → molecules resist pulling apart

Solvent

majority of a solution

solute

dissolved in a solvent

Solvency

the ability of water to dissolve and separate ions (atoms with different charges)

Hydration Spheres

the partial negative charge orients toward a positively charged ion and vice versa

Thermal Regulation of water

Water has a high heat capacity, Hydrogen bonding allows water to resist changes in temperature (absorbs and releases elsewhere) bonds break then liquid water becomes a gas and large amounts of heat are released

Neutral

Water is neutral pH (7), allows for cellular processes that would not be able to occur in basic (alkaline) or acidic solutions can occur in water

Acids

molecules that release H+ when dissolved in water, increase hydrogen ions (H+ ) levels in solution

Bases

molecules that absorb H+ from solution, decrease hydrogen ions (H+ ) levels in solution

How are gases obtained in the body?

cellular respiration, Gases are used to generate energy (O2 → ATP) and remove waste products (CO2 )

How are minerals obtained in the body?

diet, Minerals play a variety of roles in physiological processes (ex. Calcification of bone - Action potentials in muscles and nerves

What are molecules of life composed of?

organic components (Carbohydrates, Lipids, Nucleotides (DNA, RNA, ATP, etc.), Proteins

Properties of Carbon

Can bond with 4 other atoms • Can form single, double, and triple bonds • If there is at least 1 double or triple bond the carbon is unsaturated

Carbons can link together in chains. Chemical properties of the chain are determined by:

Length of chain + Functional groups associated with chain

Macromolecules

are large organic molecules that contain thousands of linked atoms

Polymers

macromolecules consisting of repeating units (monomers)

Carbohydrates

polar and usually water soluble, Energy source, makes up Glucose - Small sugars can dissolve and flow through the blood - Large sugars are broken down during digestion into small, useable parts - Structural roles In DNA + At the cell surface

Monosaccharides

1 carbon ring composed of 5 or 6 carbon atoms

Disaccharides

formed when 2 monosaccharides bond

Polysaccharides

complex sugars composed of many linked monosaccharides

Starch

a plant polysaccharide consisting of straight or slightly branched lines of glucose monomers (used for energy storage)

Glycogen

an animal polysaccharide consisting of highly branched lines of glucose monomers - stored in the liver and muscle cells - Broken down into glucose when blood sugar drops

Lipids

water insoluble, hydrophobic molecules that are composed mostly of C and H, What do they do? - Energy source, Insulation - Compose cell membranes - Structural support for cells - Participate in signaling/ cellular communication