In what stage of mitosis do all chromosomes align in one plane?
A cell in interphase is sometimes said to be resting. Which is this misleading?
--interphase cells are synthesizing RNA and protein and growing is size
Which is not found in a plant cell?
The network of fibers that helps the cell maintain its shape and give support to the cell is called the
In most cases protein kinases:
--add phosphate groups to proteins
L-glucose, D-glucose and fructose are examples of?
Which of the following statements concerning unsaturated fats are correct?
--they have double bonds in the carbon chains o their fatty acids.
The tertiary structure of a protein is typified by the?
--Three dimensional shape of an individual polypeptide caused y the bonding between R groups
Which is a type of interaction that stabilizes the alpha helix structure of proteins?
Which element is found in both nucleic acids and all proteins?
Polysaccharides, nucleic acids, and proteins are all polymers synthesized from monomers b?
--The removal of water from each pair of monomers.
Which of the following descriptions best fits the class of molecules known as nucleotides?
--Five carbon sugar, a nitrogenous base and a phosphate group.
The disaccharide maltose is composed of two molecules of glucose inked by a:
--alpha 1-4 bond
The bond(s) responsible o primary protein structure is/are?
Water plays a role in many cells. Which of the following is NOT a property of water?
--It dissociates completely into H+ and OH-
Glucose and hexanoic acid which contain 6 carbon atoms, but they have completely different properties. Glucose is necessary for food; hexanoic acid is poisonous. Their differences must be due to different?
A molecule that has all nonpolar covalent bond would be:
In a group of water molecules, hydrogen bonds form between:
--The oxygen atom in one molecule and a hydrogen atom in another molecule.
Which of the following statements about primers used in PCR is not true:
--they complement the DNA of the same strand of the template.
Which end of the PCR primer can be extended by polymerase?
--the 3� end
The lock and key hypothesis attempts to explain the mechanism of?
A catalyst is a substance which:
--increases the rate of a chemical reaction but itself unchanged by the reaction
The alpha helix, beta sheets are examples of the
The class of enzymes that split peptide bonds or glucosidal bonds wither water is
When the bond that produces the tertiary structure of a protein is disrupted by agents such as heat, acid or heavy metal ions, this process is known as?
If a compound is a competitive inhibitor
--the addition of more substrate reverses the inhibition
Which structure is only found in animal cells?
The ______________destroys worn out cells or cell organelles. Sometimes this is called the �suicide sac�. This sac contains hydrolytic enzymes for this purpose.
Amanda is viewing cells using a light microscope. In her observations, she vies a nucleus and a cell wall. Which additional organelles is she most likely to observe using the light microscope in this observation?
Cyanide, a metabolic poison, interferes with the cellular aerobic production of ATP. Which cell organelles does cyanide most directly influence first in this situation?>
Semiconseravative replication of DNA means
--A single strand of DNA is copied to make two single strands of DNA.
DNA replication begins at a specific site called the
Which of the following are limitations of DNA polymerase?
--it can only add bases it the exposed 3� end of a pre-existing strand
Which of the following is requiring for DNA replication to occur?
Okazaki fragments form during DNA replication because
--The DNA molecule is ant parallel
What is the significance of selective permeability to biological membranes?
--selective permeability allows the plasma membrane to control traffic
into and out of the cell it surrounds.
--selective permeability allows
cells to concentrate particular ions on either side of the
--selectively permeability prevents toxic materials from
entering the cell
--selective permeability permits the selective uptake
of nutrients and the elimination of wastes.
What is the first step in the process of DNA replication?
Helicases must unwind (break) the bonds between base pairs.
Which if the following statements concerning membrane proteins are incorrect?
--they are not particular about what types of chemicals they will allow to cross the membrane.