BSC2010 Ch.4
The organelles and biomolecules present in homogenized cells can be separated by centrifugation. Which of the following would be found at the top of a centrifugation gradient?
ATP molecules
Which organelles are involved in energy conversions?
Chloroplasts
Which statement about the nucleus of animal cells is true? A. It occupies the smallest volume of the cell. B. It powers the cell. C. It is enclosed by a single membrane. D. DNA in the nucleus combines with proteins. E. The nucleus is the site of protein synthesis.
D
Which is an advantage of eukaryotic cell structure over prokaryotic cell structure?
Different cell functions are compartmentalized and kept separate from one another in membrane-bound organelles in eukaryotic cells.
Besides the proteins being processed for distribution, what other components could be expected to be found inside the Golgi apparatus?
Enzymes
Which organelle(s) is/are found only in plants?
Glyoxysomes
Liver cells are exposed to radioactive amino acids, making all proteins synthesized during this time radioactive. The cells are then removed at 5-minute intervals and fractionated. Where in the cells is the radioactively-labeled enzyme lipase performing its intracellular functions?
In lysosomes
Which protein(s) power(s) the movement of both cilia and vesicles within a cell?
Kinesin and dynein
Which structure(s) is/are directly involved in the movement of organelles within a cell?
Microtubules
In a multicellular organism, different cells are specialized for certain functions to help the whole organism maintain the living state. As cells differentiate to become specialized, the abundance of different organelles shifts to best serve those needs. Which organelle might be expected to be present in high abundance in a mammal's muscle cells that must extract large amounts of energy from food molecules to support the work of muscle contraction?
Mitochondrion
Which structure is known for its lack of nucleic acids?
Plant vacuole
What happens to proteins as they pass through the Golgi apparatus?
Proteins are modified by having sugars attached or removed.
Amoeba proteus is injected with a drug that inhibits the formation of microtubules. What effect will this have on the organism's movement?
The drug will have no effect on the organism's movement.
A student discussing the role of the Golgi apparatus in cells makes the following three statements: A variety of proteins enter the Golgi from vesicles that pinch off from the rough ER. Within the Golgi apparatus, different proteins are modified by the activities of sugar molecules. After modification, the proteins move within vesicles to specific locations in the cell. Evaluate the accuracy of the student's statements.
The first and third statements are accurate; the second statement is not accurate.
Which structure occupies the largest volume in a mature plant cell?
Vacuole
The proteins that make up the cytoskeleton of bacteria are similar to _______ in eukaryotic cells.
actin
Prokaryotes
are surrounded by a cell membrane.
The correct order of movement of proteins through the Golgi apparatus is
cis, medial, trans.
The extracellular matrix of animal cells
contains proteoglycans
DNA strands are visualized using a(n)
electron microscope.
Of the following, the _______, which is enclosed in a membrane, has the greatest amount of internal surface area.
endoplasmic reticulum
Cilia and eukaryotic flagella
must have a motor protein that uses the energy of ATP hydrolysis to power movement.
The endomembrane system
ncludes the Golgi apparatus and the endoplasmic reticulum.
Plastids are
present in nearly all plant cells.
Some proteins that are on the surface of mammalian cells contain carbohydrates. These proteins are synthesized by _______ and the carbohydrates are added in the _______.
the rough endoplasmic reticulum; Golgi apparatus
The presence of _______ means that substances must pass through, rather than between, the epithelial cells that form the lining of the small intestine.
tight junctions
