Biolofy Exam Semester 1

prokaryote

prokaryote

unicellular organism that lacks a nucleus and membrane-bound organelles

eukaryote

organism whose cells contain a nucleus and membrane-bound organelles

control

In an experiment, the standard that is used for comparison

control trial

measures the performance of one set of task components in the absence of another set of task components to isolate the effects of the included components on performance.

slope

rise/ run (y2-y1/x2-x1)

suspension

a heterogeneous mixture that separates into layers over time

solution

a homogeneous mixture of two or more substances

product

a substance that forms in a chemical reaction

reactant

a substance that takes part in and undergoes change during a reaction.

solvent

the substance in which the solute dissolves

solute

the substance that is dissolved

exothermic

releases energy, heat

endothermic

absorbs energy, heat

catabolic

breaking down (cats destroy)

anabolic

building up, creating

atomic number

number of protons

atomic mass

number of protons and neutrons

protons

positive charge

neutrons

neutral charge

electrons

negative charge

ions

positively and negatively charged atoms

ionic bonds

transfer of electrons

polar covalent bond

unequal sharing of electrons

nonpolar covalent bond

equal sharing of electrons

hydrogen bonds

weak attraction between a hydrogen atom and another atom

monomers

small unit that can join together with other small units to form polymers

structure of proteins

amino acids

function of proteins

growth and repair

examples of proteins

enzymes and antibodies

structure of carbohydrates

carbon, hydrogen, and oxygen in a 1:2:1 ratio

function of carbohydrates

provide energy

examples of carbohydrates

sugars, starches, chitin, glycogen, cellulose, glucose

function of starch

energy storage in plants

function of glycogen

energy storage in animals

function of cellulose

provides support to plant cell walls

function of chitin

provides structure to fungal cell walls, exoskeleton

function of glucose

quick energy

structure of lipids

long fatty acids attached together to make long chains

function of lipids

long term energy storage

examples of lipids

fats, oils, waxes, steroids

hydrophobic

water hating

hydrophilic

water loving

are lipids hydrophilic?

no

structure of nucleic acids

nucleotides

function of nucleic acids

store genetic information

examples of nucleic acids

DNA, RNA, ATP

cohesion

an attraction between molecules of the same substance

adhesion

attraction between molecules of different substances

surface tension

the force that acts on the surface of a liquid and that tends to minimize the area of the surface

high heat of vaporization

many hydrogen bonds must be broken for water to evaporate

high specific heat

the ability of water to resist changes in temperature

is frozen water less dense than liquid water?

yes

is water a good solvent?

yes

what are found in all cells?

ribosomes, cytoplasm, plasma membrane, DNA

structure of plasma membrane

phospholipid bilayer

function of plasma membrane

to regulate what goes into and out of the cell

function of nucleus

contains DNA

function of ribosomes

make proteins

function of the rough endoplasmic reticulum

protein synthesis

function of smooth endoplasmic reticulum

lipid synthesis

function of the golgi apparatus

modify, sorts and packages proteins and other materials from the ER for storage in the cell or secretion outside the cell

function of the central vacuole

stores water

function of the mitochondria

cellular respiration and atp synthesis

function of chloroplasts

site of photosynthesis

structure of cell wall

made of cellulose

function of the cell wall

protects and supports the cell

function of nucleoid

contains DNA

function of flagella

movement

function of pili

attachment (like suction cups)

function of capsule

protection

structure of the cytoskeleton

microtubules, microfilaments, intermediate filaments

function of the cytoskeleton

helps a cell keep its shape

endomembrane system

regulates protein traffic and performs metabolic functions in the cell

endosymbiotic theory

theory that eukaryotic cells formed from a symbiosis among several different prokaryotic organisms

function of cholesterol

maintains membrane fluidity

function of a phospholipid

make up the cell membrane

integral proteins

penetrate the hydrophobic interior of the lipid bilayer

function of integral proteins

transport proteins, enzymes, or receptors

peripheral proteins

bound to the surface of the membrane

function of peripheral proteins

enzymes, motor proteins for shape change during cell division and muscle contraction, cell-to-cell connections

glycoproteins

proteins that have carbohydrates covalently bonded to them

function of glycoproteins

cell recognition

glycolipids

carbohydrates covalently bonded to lipids

function of glycolipids

cell recognition

Why do phospholipids form a bilayer?

Hydrophilic heads attracted by water so are on the outsideHydrophobic tails repel water so point inwards

what does it mean that the phospholipid bilayer is flexible?

molecules can easily slide past and change position in the membrane

what does it mean that the phospholipid bilayer is fluid?

with the help of cholesterol, the membrane can move and even stretch

fluid mosaic model

model that describes the arrangement and movement of the molecules that make up a cell membrane

passive transport

the movement of substances across a cell membrane without the use of energy by the cell from a high to low concentration

simple diffusion

movement of a solute from an area of high concentration to an area of low concentration

facilitated diffusion

process of diffusion in which molecules pass across the membrane through cell membrane channels

osmosis

diffusion of water

hypertonic

having a higher concentration of solute than another solution.

hypotonic

having a lower concentration of solute than another solution

isotonic

having the same solute concentration as another solution.

semipermeable membrane

a membrane that allows some molecules to pass through but does not allow other molecules to pass through.

active transport

the movement of materials through a cell membrane using energy from a low to high concentration

structure of enzymes

made of proteins

function of enzymes

increase the rate at which a reaction occurs by lowering the activation energy and provides a place for reactions to happen

substrate

reactant of an enzyme-catalyzed reaction