Anatomy - Exam 1

hierarchy

organism-organ systems-organs-tissues-cells-organelles-macromolecules-molecules-atoms

reductionism

large/complex systems can be understood by studying its simpler components

holism

emergent properties of an organism cannot be predicted using the properties of separate parts

characteristics of life

organization, cellular composition, metabolism, responsiveness, movement, homeostasis, development, reproduction, and evolution

homeostasis

maintaining relatively stable conditions

metabolism

all chemical reactions of the body

causes of physiological variation

sex, age, weight, activity levels, genetics, and environment

negative feedback loop

a mechanism that counteracts a change to bring a system back to its set point or stable state

positive feedback loop

a mechanism that amplifies or intensifies a change, moving the system further away from its initial state

11 organ systems

integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive

causes of anatomical variation

natural selection, mutation, and recombination

concentration gradient

movement from high to low concentration; oxygen from the lungs is diffused into the bloodstream

pressure gradient

movement from high to low pressure; blood flows from the aorta to the rest of the body

electrical gradients

charged particles flow down the gradient; Sodium flowing down into a neuron

Thermal gradient

Heat flows down the gradient; heat from the arteries moves out toward the skin

4 classes of organic molecules

carbohydrates, fats, lipids, and nucleic acids

minerals

inorganic elements extracted from soil by plants and passed up the food chain to humans

vitamins

organic compounds made by plants or animals that can be broken down by heat or air

hydroxyl (OH)

sugars and alcohols

methyl (CH3)

fats, oils, steroids, and amino acids

carboxyl (COOH)

amino acids, sugars, and proteins

amino (NH3)

amino acids and proteins

Phosphate (H2PO4)

nucleic acid and ATP

carbohydrates

hydrophilic organic molecules with a 2:1 ratio of hydrogen to oxygen; monosaccharide building blocks

ex. glucose and starch

types of carbs

monosaccharide, disaccharide, oligosaccharide, and polysaccharide

function of carbs

body’s primary energy source

lipids

hydrophobic organic molecules; long CCH chain

ex. fats and oils

types of lipids

fatty acids, triglycerides, phospholipids, steroids, eicosanoids

saturated fatty acid

no double bonds (more hydrogens)

unsaturated fatty acids

double bonds between carbons

triglycerides

three fatty acids linked to glycerol

phospholipids

similar to neutral fats except one fatty acid is replaced by a phosphate group

steroid

lipid with 17 carbon atoms in four rings

protein

polymer of amino acids

ex hemoglobin and muscle proteins (actin)

amino acid

Central carbon with three attachments - amino group, carboxyl group (–COOH), and R group

joined by peptide bonds

protein function

depends on its shape

nucleic acid

stores, transmits, and expresses genetic info. Made of A,C,G,T, and U

ex. DNA and RNA

enzyme

proteins that function as biological catalysts, by lowering activation energy

ex. Red/Ox rxn

variables that affect the rate of a reaction

temperature, concentration (or pressure for gases), surface area, the presence of a catalyst, and the nature of the reactants

why is water a good solvent

due to its polarity and ability to form hydrogen bonds

mixture

physically combined, but not chemically

compound

chemically combined

Solution vs colloid vs suspension

Solutions are homogeneous mixtures with tiny particles (<1 nm) that do not settle or scatter light (e.g., salt water). Colloids are intermediate (1-1000 nm), heterogeneous mixtures that scatter light but do not settle (e.g., milk, fog). Suspensions are heterogeneous, large-particle (>1000 nm) mixtures that settle and can be filtered (e.g., muddy water). 

buffers

resist change in pH

what happens to solutes when placed in water

Water dissolves ionic and polar substances, but not nonpolar ones

hypotonic

cell absorbs water and swells

hypertonic

cell loses water and shrivels

nucleus

controls the cell

nucleolus

makes ribosomes

ribosomes

site of protein synthesis

lysosomes

digests waste

vacuoles

storage

4 components of a cell

plasma membrane, cytoplasm, DNA, ribosomes

microvilli

increases surface area

ex. kidney tubules

cilia

move substances

ex. inner ear

flagella

cell movement

ex. sperm

tonicity

• Hypotonic → cell swells

• Hypertonic → shrinks

• Isotonic → no change

diffusion

movement from high solutes to low solutes

variables affecting diffusion rate

• Concentration gradient

• Temperature

• Surface area

• Distance

• Molecule size

hyperplasia

growth through cell multiplication

hypertrophy

enlargement of preexisting cells

neoplasia

tumor

tissue regeneration

replacing cells with cells

fibrosis

replacing cells with scar tissue

gangrene

tissue necrosis due to insufficient blood supply