Chapter 3 Quiz Flashcards
know how to label the cell
page 63
know how to label plasma membrane
page 64
simple diffusion
nonpolar and lipid soluble substances diffuse directly through the lipid bi layer
which of the following would not diffuse through the plasma membrane by means of simple diffusion?
glucose
which cell component helps to maintain the structural integrity of the cell?
cytoskeleton
cytoskeleton
it acts as cells bones, muscles and ligaments by supporting cellular structures and providing the machinery to generate various cell movements
During which phase of the cell cycle does DNA duplication, or replication, take place?
Interphase
When a double helix of DNA is replicated, two complete helices are formed. Together, these helices are called sister __________.
chromatids
During which phase of mitosis do sister chromatids line up at the center of the cell?
metaphase
During which phase of mitosis do the sister chromatids move apart?
anaphase
During which phase of mitosis do nuclear envelopes and the nucleoli reappear?
Telophase
During which phase of mitosis do the nuclear envelope and nucleoli disappear?
prophase
What is the name of the process by which the cytoplasm divides in two?
cytokinesis
A primary active transport process is one in which __________.
molecules move through transport proteins that have been activated by ATP
Some transport processes use transport proteins in the plasma membrane, but do not require ATP. This type of transport is known as _____.
facilitated diffusion
The majority of water molecules moving across plasma membranes by osmosis do so via a process that is most similar to ____.
facilitated diffusion
The sodium-potassium pump uses ATP to move sodium and potassium ions across the plasma membrane. This statement describes _____.
primary active transport
A vesicle fuses with the plasma membrane and releases its contents to the extracellular fluid. This statement describes _____.
exocytosis
Solutions with a higher concentration of solutes than the concentration inside the cells are __________.
hypertonic
Which organelle is responsible for synthesizing proteins?
ribosomes
After DNA replication is completed, each DNA double helix consists of ______.
one old parent strand and one new daughter strand
What must happen before a body cell can begin mitotic cell division?
Its DNA must be replicated exactly so that identical copies of the cell’s genes can be passed on to each of its offspring.
The plasma membrane is made primarily of ________.
phospholipids
Which mechanism requires energy input by the cell in the form of ATP hydrolysis?
page 69 NONE OF THE MECHANISMS REQUIRE ENERGY INPUT
A red blood cell placed in pure water would ________.
swell and burst
Which vesicular transport process occurs primarily in some white blood cells and macrophages?
phagocytosis
Lysosomes perform digestive functions within a cell.
True
What is the primary function of the mitochondria?
They are the main sites of ATP production.
Which of the following is characteristic of cilia?
They are whiplike, motile cellular extensions that occur in large numbers on the exposed surfaces of certain cells.
Which of the following is a function of the rough endoplasmic reticulum?
synthesis of the cell’s membranes
Houses DNA and RNA.
nucleus
Dense spherical bodies in the nucleus that are the synthesis site for ribosomal RNA.
nucleoli
Hollow cytoskeletal elements that act as organizers for the cytoskeleton.
microtubules
The actual site of protein synthesis.
ribosomes
Plays a role in the synthesis of steroid-based hormones and proteins
endoplasmic reticulum
what is the function of the cell membrane?
defines extent of a cell; separating two of the bodies major fluid components. intracellular on the inside and extracellular on the outside
what is the membrane constructed of ?
phospholipids, glycolipids, cholesterol and lipid rafts
hydrophilic
water lover; polar head that is charged
hydrophobic
fear of water; uncharged non polar tail
function of the phospholipids in the membrane
hydrophobic heads lie on the surface of both intercellular and extracellular surface and the hydrophobic lie in the middle; self-assemble into closed generally spherical structures to reseal themselves when torn
what is the function of glycolipids?
are lipids attached with sugar groups; polar; 5% of the membrane
what is the function of cholesterol in the membrane?
20% of the membrane; has a polar region and a nonpolar region; it stabilizes the membrane while decreasing the mobility of the phospholipids and the fluidity of the membrane
membrane proteins
allows communication with the environment
