Quiz 2 Flashcards
In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis?
On the inside surface of the vesicle
Thylakoids, DNA, and ribosomes are all components found in
Chloroplasts
Primary objective of cell fractionation is to
Separate the major organelles so that their particular functions can be determined
A protein that spans the phospholipid by layer one or more times
A transmembrane proteins
A cell with a predominance of free ribosomes is most likely
Producing primarily cytoplasmic proteins
Which of the following contains hydrolytic enzymes
Lysozyme
Prokaryotes are classified as belonging to two different domains. What are those domains?
Bacteria and Archea
Which of the following is a reasonable explanation for why unsaturated fatty acid’s help keep any membrane more fluid at lower temperatures
The double bonds form kinks in the Fatty acid tails preventing adjacent lipids for packing tightly
Which plant cell organelle contains it’s own DNA and ribosomes?
Mitochondria
The presence of cholesterol in the plasma membrane’s of some animals
Enables the membrane to stay fluid more easily when cell temperatures drops
Movement of vesicles within the cell depends on the cellular structures
Microtubules and motor proteins
In a plant cell, DNA may be found:
In the nucleus, mitochondria, and chloroplasts.
Diffusion
It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration
White blood cells engulf bacteria through what process
Phagocytosis
A bacterium engulfed by white blood cell through phagocytosis will be digested by enzymes contained in:
Lysosomes
Ions diffuse across membranes there specific ion channels
Down there electrochemical gradients
Which structure is the site of synthesis of proteins that may be exported from the cell
Rough endoplasmic reticulum
In order for a protein to be an integral membrane protein it would have to be
Amphipathic, with at least one hydrophobic region
According to the fluid Mosaic model of cell membranes, which of the following is a true statement the membrane phospholipids
They can move laterally along the plane of the membrane
Which of the following is a characteristic feature of the carrier protein in a plasma membrane
It exhibits a specificity for the particular type of molecule
Which of the following produces and modified’s polysaccharides that will be secreted:
Golgi apparatus
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules
Proteins
Which animal cell organelle contains enzymes that transfer hydrogen various substrates to oxygen
Peroxisome
All of the following are part of a prokaryotic cell except
And endoplasmic reticulum
Water passes quickly through so membranes because
It moves through aquaporn’s in the membrane
Which type of organelle or structure is primarily involved in the synthesis of all oils phospholipids and steroids
Smooth endoplasmic reticulum
Which of the following are not embedded in the hydrophobic portion of the lipid bilayer at all
Peripheral proteins
The primary function of polysaccharides attached to glycoproteins and glycolipids og animal cell membranes is:
To mediate cell to cell recognition
The Balian good equivalent of 0.15 M NaCl. Seawater contains the equivalent of 0.45 M NaCl. What will happen if red blood cells are transferred to seawater?
Water will leave the cells causing them to shrivel and collapse
What kinds of molecules pass through a cell membrane most easily
Small and hydrophobic
Which of the following is true of integral membrane proteins
They are usually transmembrane proteins
Which of the following would likely move through the lipid bilayer of plasma membrane most rapidly:
CO2
The difference between Pinocytosis and receptor mediated endocytosis is that
Pinocytosis is nonselective in the molecules it brings into the cell, where is preceptor mediated endocytosis offers more selectivity
In a liver cell detoxifying alcohol and some other poisons, the enzymes of the Piro peroxisome remove hydrogen from these molecules and
Transfer the hydrogen to oxygen molecules to generate hydrogen Prock
Signals between the ECM in the cytoskeleton may be transmitted by
Integrins
Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of anither through
Gap junctions
What is the voltage across a membrane called
Membrane potential
Which organelle is the primary site of ATP synthesis in eukaryotic cells
Mitochondria
Which of the following types of molecules are major structural components of the cell membrane
Phospholipids and proteins
mRNA and ribosomal subunits are made in this organelle
The nucleus
The organelle that is considered as the little net can synthesize lipids and secretory lipids are called
Smooth endoplasmic reticulum and Rough endoplasmic reticulum respectively
Why isn’t the mitochondrion classified as part of the endomembrane system
It’s structure is not derived from the ER or golgi apparatus
One of the primary difference between prokaryotic cells and eukaryotic cells is
Prokaryotic cells do not have membrane-bound organelle’s
The organelle that a specialist in synthesizing sugar using certain pigments such as chlorophyll is the
Chloroplast
The organelle that produces hydrogen peroxide and and I just other toxic metabolic byproducts is the
Peroxisome
The shape and structure of the cell is maintained bye
Microtubules and microfilaments
Small molecules such as ions can move from one cell to another via
Gap junctions
Ions diffuse across membranes through specific ion channels
Down their elecrochemical gradient
Variation in charge across the plasma membrane is called
Membrane potential
