Bio 1010 Exam 2 (Durbak- Mizzou)

osmosis

diffusion of water across membrane; always moves from where there is LESS solute to MORE solute

isotonic

if the amount of solute surrounding the cell is the same as amount inside the cell

hypertonic

the amount of solute in the liquid surrounding the cell is greater than the amount of solute inside the cell

hypotonic

the amount of solute in the liquid surrounding the cell is less than the amount of solute inside the cell

turgor

swelling of cells against the cell wall; helps keep plants upright

osmoregulation

balancing water and solute concentration to prevent cells from bursting; animal cells

solvent

water is the universal__________.

solutes

anything that is dissolved

osmosis

movement of water

diffusion

movement of the SOLUTE from an area of higher concentration to lower concentration

passive transport

diffusion of a molecule (solute) across a membrane

concentration gradient

substance move from where there is more solute to where there is less

facilitated diffusion

helps the movement of larger molecules across a membrane with the help of transport proteins; does not require energy; goes from higher solute concentration to lower solute concentration

active transport

requires energy; movement of molecules across a membrane from an area of lower solute concentration to an area of higher solute concentration

cytoplasm

everything in a cell, except for the contents of the nucleus

cytosol

everything inside the cytoplasm that is not inside any organelles

nucleus

the organelle in eukaryotes that contains the DNA that is packaged as chromatin

chromatin

DNA wound around proteins

nuclear envelope

separated from the rest of the cell by a double membrane; contains nuclear pores that allow movement of molecules in and out

nucleolus

where ribosomes are made

endomembrane system

system of organelles in eukaroytic cells where proteins and lipids are made and transported throughout the cell

endoplasmic reticulum

connected to the nuclear envelope, where proteins and lipids are made

rough ER

covered in ribosomes, proteins and membranes are made

smooth ER

no ribosomes, makes steroids, and detox enzymes

Golgi apparatus

series of stacked membrane discs that package proteins and prepare them for transport

vesicles

connected to the ER; small membrane-bound sacs that carry items around the cell

lysosomes

membrane-bound sacs that contain digestive enzymes; found in animal cells

vacuoles

large sacs of membrane that function as storage for nutrients, water, etc.

cytoskeleton

protein fibers that extend throughout the cytoplasm, anchored at the plasma membrane and throughout the cell

mitochondria

organelle responsible for important energy-conversion reactions in eukaryotes

chloroplast

plant and algae specific organelle that is the site of photosynthesis

endosymbiotic theory

chloroplasts and mitochondria evolved from bacteria that were engulfed by larger bacteria; size is comparable to prokaryotes; each have two membranes

energy

the capacity to cause change; ability to work

conservation of energy

principle that energy cannot be created or destroyed, but is transformed from one form to another

kinetic energy

energy of motion or movement

potential energy

energy on an object because of the location or structure

heat energy

kinetic energy generated by the range of movements of atoms

chemical energy

potential energy stored in the bonds of biological molecules that can be released by chemical reactions

heat

All energy conversions generate some _________.

entropy

measure of the amount of disorder, or randomness of a system

calorie

the unit of energy in food

enzymes

proteins that speed up chemical reactions without being consumed by the reaction

activation energy

the energy that must be invested to start a reaction

substrate

any molecule to which an enzyme binds and acts on

active site

the part of an enzyme that binds to substrates

cellular respiration

aerobic harvesting of chemical energy from organic molecules

aerobic

requires oxygen

NADH

molecule that transfers electrons from one part of a cell to another

glycolysis

1 molecule of glucose is split into 2 molecules of pyruvic acid

citric acid cycle

final breakdown of pyruvic acid into CO2 occurs; pyruvic acid is converted to acetyl CoA

electron transport chain

electrons are transferred from NADH and FADH2 to a series of proteins

fermentation

occurs when there is not enough oxygen

anaerobic process

occurs without oxygen

photosynthesis

stomata

pores in leaves that allow for the exchange of CO2 and O2

stroma

inner compartment of chloroplast

thylakoids

small membrane sacs where chlorophyll, the pigment that is used to harvest solar energy, is found

wavelength

distance between peak-peak

electromagnetic spectrum

the range of radiation energy

photon

a unit of light energy

photosystems

clusters of pigment molecules

cell division

when a cell undergoes reproduction and two "daughter" cells are produced that are genetically identical

asexual reproduction

organisms that reproduce by making copies of themselves

sexual reproduction

requires fertilization of an egg and sperm

chromosomes

most of a cell's DNA is organized into structures called_____________

chromatin

chromosomes are made up of _____________

histones

DNA wrapped around proteins called _________

nucleosome

small sections of DNA wrap around a set of histones, forming something that looks like a bead

interphase

includes the stages of the cell cycle in which cells spend their time preparing for cell division; cells spend most of their time here

G1 phase

rapid cell growth and metabolism

S phase

DNA replication occurs

G2 phase

production of new organelles; cell prepares for division

sister chromatids

two copies of chromosomes

centromere

region of a chromosome where sister chromatids are joined

m phase (mitotic phase)

the part of the cell cycle when the cell is actually dividing

mitosis

the nucleus and its contents divide and are evenly distributed into two nuclei

cytokinesis

the cytoplasm along with the organelles is divided into two

interphase

chromosomes are relaxed; nuclear envelope is intact

prophase

chromosomes condense into "x"; nuclear envelope breaks down; mitotic spindle forms

mitotic spindle

structure made of microtubles that guides the separation of chromosomes

metaphase

spindle fibers that attach to the centromeres of the chromosomes; chromosomes line up at the center of the cell

anaphase

spindle fibers shorten, pulling sister chromatids apart to opposite sides of the cell

telophase

begins when the chromosomes reach the opposite sides of the cell; opposite of prophase; nuclear envelope reforms; chromosomes decondense; spindle fibers disapper

cytokinesis

begins during telophase; divides the cytoplasm

gametes

cells that contain combine in fertilization to make new organisms; each only has 1 copy of chromosome

haploid

half the number of chromosomes

somatic cells

include all the rest of the cells in the body and contain two copies of each chromosome

diploid

two copies of each chromosome

gametes

sperm and egg cells

somatic cells

blood cell,s cone cells, skin cells, etc.

homologous chromosomes

each pair of identical chromosomes

karyotype

a way to display all of the chromosomes in a somatic cell

autosomes

chromosomes are 1-22; homologous pairs of chromosomes and are identical to each other in both males and females

sex chromosomes

the 23rd pair; determines the sex of an organism

females

XX

males

XY

zygote

fertilization is where a haploid sperm fuses with a haploid egg to form a diploid ____________

meiosis

the process of cell division in which 1 diploid cell forms 4 haploid cells

duplicate

before the start of the meiosis, all of the chromosomes _______________

separate/new cells

In the first step of meiosis, Meiosis 1, homologous chromosomes ____________ into two __________ __________.

sister chromatids/new cells

In meiosis 2, __________ _________separate into ___________ __________.