Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
80 Cards in this Set
- Front
- Back
Cells differ notably in ____________ |
Shape |
|
________ cells vary considerably in size; all are microscopic |
Human |
|
cells contain ____________, a substance found only in cells |
cytoplasm |
|
__________ are specialized structures within the cytoplams |
Organelles |
|
______________ is surrounded by plasma membrane |
cell interior |
|
____________ forms outer boundary of cell |
plasma membrane |
|
plasma membrane is composed of thin, two-layered membrane of _________ and is embedded with ___________ |
phosholipids; proteins |
|
plasma membrane is selectively ___________ |
permeable |
|
Cytoplams is all cell substance from the _____to the __________ |
nucleus ; plasma membrane |
|
__________ is the internal framework of a cell |
cytoskeleton |
|
cytoskeleton is made up of _______ and ________ |
microfilaments; microtubules |
|
cytoskeleton provides ______ and _______ for the cell and organelles |
support; movement |
|
________ are made of two tiny subunits of mostly rIbosomal RNA (rRNA) |
Ribosomes |
|
Ribosomes may attach to _________ ER or lie free in cytoplasm |
rough |
|
Ribosomes manufacture enzymes and other proteins; often called _____________ |
protein factories |
|
A network of connecting sacs and canals are called _____________________ |
Endoplasmic reticulum (ER) |
|
ER ________ substances through cytoplasm |
carries |
|
___________ collects, folds, and transports proteins made by ribosomes |
rough ER |
|
_________ synthesizes chemicals; makes new membrane |
smooth ER |
|
_____ is a group of flattened sacs near the nucleus |
golgi apparatus |
|
golgi apparatus collects chemicals into _______ that move from the smooth ER outward to the plasma membrane |
vesicles |
|
golgi apparatus is often called the _____ and _____ of a cell |
chemical processing; packaging center |
|
_____ is composed of inner and outer membranous sacs |
mitochondria |
|
the mitochondria is involved with ______ chemical reactions (cellular respiration) |
energy-releasing |
|
mitochondria is often called __________ of the cell |
power plants |
|
each mitochondrion contains one _______ molecule |
DNA |
|
_____ are membrane-enclosed packets containing digestive enzymes |
lysosomes |
|
lysosomes have _______ function (eat microbes) |
protective |
|
lysosomes were formerly thought to be responsible for _______(programmed cell death) |
apoptosis |
|
______ is the microtuble-organizing region of the cytoskeleton near the nucleus |
centrosome |
|
_______ are paired organelles that lie at the right angles to each other within the centrosome and function in moving chromosomes during cell reproduction |
centrioles |
|
_____ is a short extension of the plasma membrane that increase surface area and produce slight movements that enhance absorption by the cell |
microvilli |
|
_____ are hairlike extensions with inner microtubules found on free or exposed surfaces of all cells; serve sensory functions, but some are also capable of moving together in a wavelike fashion to propel mucus across a surface |
cilia |
|
_____ are single projections (much longer than cilia) that act as "tails" of sperm |
flagella |
|
__________ controls the cell because it contains most of the genetic code (genome), instructions for making proteins, which in turn determine cell structure and function |
nucleus |
|
nuclear envelope, nucleoplasm, nucleolus, and chromatin granules are all ___________ of the nucleus |
component structures |
|
DNA molecules become tightly coiled chromosomes during ________ |
cell division |
|
____ nuclear chromosomes contain DNA, which contains genetic code |
46 |
|
every human cell has a designated function: some help _____ the cell and others _____ life processes |
maintain; regulate |
|
________ functions of a cell differ depending on the number and type of organelles |
specialized |
|
______ do not require added energy and result in movement "down a concentration gradient" |
passive transport processes |
|
______ occurs when substances scatter themselves evenly throughout an available space, the particles moving from high to low concentration; may thus move through channels or carriers in a membrane to reach an equilibrium (equality of concentration) |
diffusion |
|
_____ means it is unnecessary to add energy to the system |
passive process |
|
_____ is the diffusion of water (when some solutes cannot cross the membrane |
osmosis |
|
_____ is diffusion of small solute particles |
dialysis |
|
____ is the movement of water and solutes caused by hydrostatic pressure on one side of the membrane |
filtration |
|
_____ only occur in living cells; movement of substances is " up the concentration gradient" |
active transport processes |
|
____ is a protein complex in the cell membrane |
an ion pump |
|
ion pumps use energy from ____ to move substances across cell membranes against their concentration gradients |
ATP |
|
____ and _____ are examples of ion pumps |
sodium-potassium pumps; calcium pumps |
|
some ion pumps work with other carriers so that ____ or ____ are transported along with ions |
glucose; amino acids |
|
_____ or "cell eating" engulfs large particles in a vesicle as a protective mechanism often used to destroy bacteria or debris from tissue damage |
phagocytosis |
|
_____ or "cell drinking" engulfs fluids or dissolved substances into cells |
pinocytosis |
|
both pino and phago cytosis are active transport mechanisms because they require_____ to move the cytoskeleton in a way that engulfs material and pulls it into the cell |
cell energy |
|
DNA structure can be described as a large molecule shaped like a __________ |
spiral staircase |
|
______ and ______ units compose the sides of the DNA molecule |
sugar (deoxyribose); phosphate |
|
base pairs _________ or _______ compose the "steps of the DNA molecule |
adenine-thymine; guanine-cystosine |
|
the base pairings are always the same (complementary base pairing), but the _______ of base pairs differs in different DNA molecules |
sequence |
|
a _______ is a specific sequence of base pairs within a DNA molecule |
gene |
|
genes dictate formation of enzymes and other proteins by ribosomes, thereby indirectly determining a cell's structure and functions; in short; genes are _______ |
hereditary determinants |
|
_______ is stored in base-pair sequences on genes and expressed through protein synthesis |
genetic information |
|
__________ occurs in cytoplasm; thus genetic information must pass from the nucleus to the cytoplasm |
protein synthesis |
|
the process of transferring genetic information from nucleus to cytoplasm where proteins are produced requires completion of _______ and _____ |
transcription; translation |
|
during _______ double-stranded DNA separates to form messenger RNA, each strand of mRNA duplicates a particular gene from a segment of DNA, and mRNA molecules pass from the nucleus to the cytoplasm where they direct protein synthesis in ribosomes and ER |
transcription |
|
______ involves the synthesis of proteins in cytoplasm by ribosomes |
translation |
|
translation requires use of information contained in ______ |
mRNA |
|
____ is a series of three nucleotide bases that acts as a code for a specific amino acid; involved in translation |
codon |
|
_____ is the reproduction of the cell involving the division of the nucleus (mitosis) and the cytoplasm |
cell division |
|
_____ result from the division of a cell |
two daughter cells |
|
period when the cell is not actively dividing is called ______ |
interphase |
|
______ helps stabilize the phospholipid molecules to prevent breakage of the plasma membrane |
cholesterol |
|
______ is the process by which each half of a DNA molecule becomes a whole molecule identical to the original DNA molecule; precedes mitosis |
DNA replication |
|
____ is the process in cell division that distributes identical nuclear choromosomes (DNA molecules) to each new cell formed when the original cell divides; enables cells to reproduce their own kind; makes heredity possible |
mitosis |
|
____ is the first stage of mitosis; chromatin granules become organized; chromosomes appear; centrioles move away from nucleus; nuclear envelope disappears, freeing genetic material; spindle fibers appear |
prophase |
|
____ is the second stage of mitosis; chromosomes align across center of cell; spindle fibers attach themselves to each chromatid |
metaphase |
|
____ is the third stage of mitosis; centromeres break apart; separated chromatids are now chromosomes; chromosomes are pulled to opposite ends of cell; cleavage furrow develops at end of stage |
anaphase |
|
____ is the fourth stage of mitosis; cell division is completed; nuclei appear in daughter cells; nuclear envelope and nucleoli appear; cytoplasm is divided (cytokinesis); daughter cells become fully functional |
telophase |
|
results of cell division include: two identical cells, ______ tissues or the _______ of old or damaged cells |
growing; replacement |
|
____ is the process by which daughter cells can specialize and form different kinds of tissue |
differentiation |
|
______ of mitotic division can produce benign or malignant neoplasms (tumors) |
abnormalities |