FINAL EXAM (BIOL)

community

community

a group of organisms in an ecosystem

population

individual species inhabiting communities

organism

individual living things

emergent properties

arrangement and interactions of parts as complexity increases

prokaryotic cells

bacteria and archaea

eukaryotic cell

all other forms of cells that are not bacteria and archaea

genomics

a system biology approach to study full sets of genes

system biology

interactions with emergent properties

ecosystem

all living things in a particular area-living and nonliving

what are the four elements most abundance in the human body

carbon, hydrogen, oxygen, and nitrogen

matter

anything that takes up space and has mass

atom

smallest stable unit of matter

cations

positively charged ions

anions

negatively charged ions

ions

acquire an electrical charge by losing or gaining electrons

mass number

number of protons + number of neutrons

atomic number

number of protons

isotopes

an element have the same atomic number but different neutrons

radioactive isotopes

unstable isotopes where the nucleus decays spontaneously, giving off detectable particles and energy

chemical bonds

formed when atoms interact & complete their valence shells

covalent bonds

formed when pairs of electrons are shared between the atoms

electronegativity

attraction of an atom for electrons

non polar covalent bonds

electrons are shared equally; there is no difference in electronegativity

polar covalent bonds

electrons are not shared equally because the atoms differ in electronegativity

ionic bond

attraction between a cation and an anion

molecule

two or more atoms held by covalent bonds

compound

two or more different elements combined in fixed ratio

ionic compound/salt

compound is formed by ionic bonds

acid

a substance that increase H+

base

a substance that decreases H+

pH

a measure of the hydrogen ion concentration

buffer

minimize the change in solution by either accepting excess H+ or donating H+

cohesive behavior

H-bonds hold water molecules together

surface tension

measures how difficult it is to stretch or break surface of liquid

moderation temperature

average kinetic E

high specific heat

amount of heat that must be absorbed or lost for 1 g of substance to change temperature by 1 C

high heat of vaporization

amount of heat liquid must absorb for 1 g be converted from liquid to gas

four bonds

how many bonds can carbon form

carbon skeleton variety

length, double bond position, branching, and presence of rings

nucleus

contains DNA

nucleolus

makes RNA, subunits of ribosomes, contains genetic info

nuclear envelope

has nuclear pores, inner/outer membrane; regulates transportation of molecules between nucleus & cytoplasm

nuclear lamina

net-like protein filaments, support envelope

ribosomes

protein synthesis; made in nucleolus

free ribosomes

suspended in cytosol; first step of sugar breakdown

bound ribosomes

attached to the ER; made proteins to destined to be inserted in the membrane

ER

biosynthetic factory → continuous with outer membrane envelope

ER structure

cisternae (sacs) and lumen (cavity)

smooth ER

no ribosomes, lipid synthesis, Ca²⁺ storage, metabolizes carbs, detox poisons/drugs

rough ER

ribosomes, make proteins, adds carbs, make phospholipids

golgi apparatus

warehouse of the cell; modify ER proteins, polysaccharide synthesis, sorting/packaging vesicles

golgi structure

flattened stacks of membranous sacs

mitochondria

powerhouse of the cell, cellular respiration

mitochondria structure

inner/outer membrane, cristae (folds in inner membrane, ATP synthesis), and matrix (inside gel; enzymes/mDNA/ribosomes)

lysosomes structure

membranous sacs with hydrolytic enzymes → made in RER; acidic on the inside

lysosomes

phagocytosis/autophagy (recycling of organic material)

peroxisomes

breaks down fatty acids

peroxisome oxidation

1. RH₂ + O₂ —> H₂O₂

2. H₂O₂ —> 2 H₂O + O₂

chloroplast

photosynthesis

chloroplast structure

inner/outer membrane, stroma (liquid on inside), thylakoid (chlorophyll)

cytoskeleton

network of fibers essential to cellular function/structure, organizes, support, and motility

motor proteins

interact for cell motility

microtubules

hollow tubes, 25 nm, a & b tubulin

microtubules function

cell shape, cell motility (motion of flagella and cilia), vesicle highways

intermediate filaments

coiled protein cables, 8-12 nm, protein vary (keratin)

intermediate filaments structure

cell shape, nuclear lamina, organelle positioning

microfilament

two intertwined protein strands, 7 nm, made of actin

microfilaments structure

muscle contraction → myosin, cytoplasmic streaming, cell crawling, animal cell division

ECM

adhesion, support, movement, regulation of the extracellular side of the cell; acts like the glue

components of ECM

collagen, fibronectin, proteoglycan complex, integrals, microfilaments

cell junction

tight junctions, desmosomes, gap junctions

tight junctions

prevent leakage between cells

desmosomes

fastens the cells together

gap junctions

cytoplasmic channel between adjacent cells

plasma membrane

selective boundary surrounding all cells; selectively permeable, acts a gatekeeper, creates different chemical environments

lipids

phospholipids, amphipathic, cholesterol → 4 fused rings structure

proteins

integral: span membrane

peripheral: loosely associated with membrane

variety of proteins function

transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining, attachment to cytoskeleton, and ECM

carbohydrates

short, branched chains; extracellular (outside) side of membrane (glycoproteins and glycolipids)

passive transport

high to low, no E required, down concentration gradient

simple diffusion

molecules slip between phospholipids(CO₂ & O₂ )

facilitated diffusion

channel proteins (aquaporins, ions), carrier proteins (glucose, amino acids)

osmosis

low solute concentration to high solute concentration to drive the movement of water

hypotonic

lysed/turgid → solute outside is lower

isotonic

normal/flaccid → plant wilts

hypertonic

shriveled/plasmolyzed → solute outside is higher

active transport

low to high, E required, against concentration

sodium-potassium pump

3 sodium out, 2 potassium in

bulk transport

moving large molecules across membrane

exocytosis

cell secretes molecule by fusion of vesicle with pl.membrane → transport of protein

endocytosis

cells take in molecules & particulate matter by forming new vesicles from pl.membrane → phagocytosis, pinocytosis, RME (LDL cholesterol uptake)

metabolism

sum of orgnaism’s chemical reactions

metabolic pathways

specific molecules altered in series of defined steps resulting in certain products → each step catalyzed by enzyme

anabolism

biosynthetic pathways (monomers → polymers), consumes E, synthesis proteins from amino acids

catabolism

breakdown/degradative pathways (polymers → monomers), released E, cellular respiration

endergonic

energy required, non-spontaneous (uphill, higher in products)

exergonic

energy released, spontaneous (downhill, higher in reactant)

cells 3 main kinds of work

chemical work, transport work, mechanical work

ATP hydrolysis

ATP —> ATP P_i (exergonic reaction)

enzyme

catalyst that speeds up reaction, lower activation energy