sudy for final

A chlorine atom has 17 protons and 18 neutrons. What is its atomic mass?

35 amu

At what temperature is water most dense?

4 degrees Celsius

How do gap junctions differ from desmosomes?

A gap junction provides communication between cells

How does a prokaryotic cell differ from a eukaryotic cell?

A prokaryotic cell has no membrane-enclosed organelles.

A beta-pleated sheet is an example of a protein's tertiary structure. __________________ T

False

A pyrimidine is a double-ring molecule. __________________

False

A(n) absorption spectrum indicates the relative effectiveness of different wavelengths of light. __________________

False

A(n) inorganic compound is one that contains carbon. __________________

False

ATP is generated when protons flow through the cytochrome complex in the thylakoid membrane. __________________

False

Biological membranes are one dimensional fluids. __________________

False

Condensation and hydrolysis reactions are catalyzed by the same enzymes.. __________________

False

Cyclic electron transport is different from noncyclic electron transport in that cyclic electron transport produces NADPH. __________________

False

Enzymes called proteases in the ER lumen catalyze folding of proteins into proper conformations. __________________

False

If you observe a cell that contains organelles, then that cell is most likely a(n) prokaryote. __________________

False

In scanning electron microscopy, an electron beam passes through a very thin slice of a specimen and then falls onto a photographic plate or a fluorescent screen.

False

Insulin stimulates cells to take in glucose by facilitated diffusion, so insulin receptor-down regulation increases the ability of cells to take in glucose. __________________

False

Mitochondria play an important role in cell necrosis. __________________

False

Most plants are known as photoheterotrophs.

False

Osmotic pressure of a solution is the amount of pressure exerted on the side of the selectively permeable containing a higher concentration of solute to prevent diffusion of solute. __________________

False

Oxidation occurs when an atom gains one or more electrons.

False

The valence shell of hydrogen or helium is unstable when it contains two electrons.

False

An organism that is neither prokaryotic nor photosynthetic, and must obtain its nutrients by secreting digestive enzymes into the environment, belongs to which group of organisms?

Fungi

____ are loosely associated with the phospholipid bilayer, whereas ____ are tightly bound to it.

Peripheral proteins; integral proteins

How does the scanning electron microscope differ from the transmission electron microscope?

The SEM gives a three dimensional image of the object being studied.

Engelmann concluded that chlorophyll in the chloroplasts is responsible for photosynthesis based on the which of the following results

The action spectrum of photosynthesis matched the maximum production of oxygen by Spirogyra, with the greatest accumulation of bacteria in the blue and red regions of the spectrum.

In cells that are constantly involved in secretion, an equivalent amount of membrane must be returned to the interior of the cell for each vesicle that fuses with the plasma membrane; if this does not occur, then what would happen?

The cell surface will keep expanding

How are integral proteins unique in cell membranes?

They are firmly bound to the membrane and can only be released with a detergent

Carotenoids are composed of isoprene subunits. __________________

True

Cyclic AMP is a type of nucleotide. __________________

True

How are chlorophyll molecules attached to thylakoid membranes?

by a long hydrocarbon side chain

ATP synthesis during the light-dependent reactions occurs by which process?

chemiosmosis

Plasmodesmata of plant cells are functionally equivalent to the ____ of animal cells.

gap junctions

A group of thylakoid discs make up what part of a chloroplast?

granum

n a lipid bilayer, __________ fatty acid tails face each other within the bilayer and form a region that excludes water.

hydrophobic

During which phase of photosynthesis is ATP and NADPH synthesized?

light-dependent phase

During phagocytosis, what may fuse with the vacuole to further degrade the ingested material?

lysosome

A single cell in a smoker's lung has become cancerous. It doubles its DNA and divides much faster than a normal lung cell. The most likely change that would have caused this condition took place in the:

nucleus

In a water molecule, because oxygen is more electronegative than hydrogen, the shared electrons are more commonly found around the ____ nucleus than the ____ nucleus.

oxygen; hydrogen

The synthesis of ATP during photosynthesis or respiration occurs as a result of what process?

phosphorylation of ADP

An organism that is eukaryotic is by definition:

possesses a nucleus