Cells and Photosynthesis Flashcards
Which of the following statements concerning cells of prokaryotes is correct?
DNA is present in prokaryotes.
Which of the following may be found in eukaryotic cells, but not in bacteria?
endoplasmic reticulum
Ribosomes are found on the surface of
rough endoplasmic reticulum
Which structure is the site of protein synthesis?
rough endoplasmic reticulum
In animal cells, which organelle contains digestive enzymes?
lysosome
Which organelle evolved through the process of endosymbiosis?
chloroplast
A(n) ______________ cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria.
animal
Which cellular structure supports cilia and flagella?
cytoskeleton
Plasmodesmata in plant cells are similar to _____________ in animal cells?
gap junctions
The fluid mosaic model says that a membrane consists of
protein molecules embedded in a phospholipid bilayer.
Which substance would diffuse through the cell membrane most slowly?
amino acids
The solutions in a U-shaped tube are separated by a selectively permeable membrane. The membrane is permeable only to water. Side A and Side B have equal concentrations of sugar. Side A is
isotonic to Side B
The solutions in a U-shaped tube are separated by a selectively permeable membrane. The membrane is permeable only to water. Side A contains the lower concentration of sugar (solute). Side A is
hypotonic to Side B
Which process requires ATP?
movement of sodium ions against the concentration gradient
Which of the following processes includes all the others?
passive transport
Breaking down large molecules into smaller ones is
catabolism
Endergonic reactions
require energy
During catabolism, what happens to the heat that is lost from the reactions?
It is released to the environment.
An enzyme _______
is not used up in the reaction
In the metabolic pathway, X → Y → Z → A, product A binds to the enzyme that converts X to Y, but not at its active site. This decreases the enzyme’s activity.
What is substance A?
a noncompetitive inhibitor
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
proteins
The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and therefore abundant in liver cells?
smooth ER
What is one function of the Golgi apparatus?
protein modification
In an animal cell, DNA may be found
in the nucleus and mitochondria.
Which organelle is NOT part of the endomembrane system?
mitochondrion
Which cellular structure helps maintain cell shape?
cytoskeleton
For the following questions, match the labeled component of the cell membrane in Figure 5.1 with its description.
Which component in the figure is cholesterol?
E
Which substance would diffuse through the cell membrane most rapidly?
O2
Human blood has a lower salt concentration than seawater. What will happen if red blood cells are transferred to seawater?
Water will leave the cells, causing them to shrivel and collapse.
Putting a red blood cell in a hypertonic solution will result in
the cell shriveling
Proteins that pump ions across membranes against their concentration gradients are an example of
active transport
Exergonic reactions _____
release energy
Metabolism is ______
all chemical reactions in a cell
ATP ____
provides energy for cellular work
Which pH curve represents the activity of an enzyme from the human stomach, where conditions are strongly acidic?
curve 4
An enzyme catalyzes the reaction, X → Y.
What is substance X?
a substrate
In animal cells, ATP synthase is located in the
mitochondrial inner membrane