are very specific, act as catalysts, are organic molecules and have special shapes that control their activities.
Enzymes may be controlled by:
temperature, the presence of chemicals that fit into allosteric sites, feedback inhibition and current metabolic conditions in the cell
Which statement is true of plasma membranes?
They have molecules on their surface that identify them.
In simple diffusion?
the rate of movement of molecules is controlled by temperature and pressure, the movement of individual molecules is random, the movement of molecules of one substance is independent of the movement of any other substance and the net movement is away from the region of highest concentration.
A single-celled freshwater organism, such as protistan, is transferred to saltwater. Which of the following is likely to happen?
The cell shrinks
Which of the following is a form of passive transport?
osmosis, facilitated diffusion, and bulk flow.
Mendel found that pea plants expressing a recessive trait:
could be produced only if one of the parents expressed the recessive trait.
If R is dominant to r, the offspring of the cross RR with rr will:
display the same phenotype as the RR parent.
If all offspring of a cross have the genotype Aa, the parents of the crosses would most likely be:
AA x aa
In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s). If a red spotter male was crossed with a black solid female black solid female and all the offspring from several crossed expressed only the dominant trait, the genotype of the female would be
An incompletely dominated gene controls the color of chickens so that BB produces black, Bb produces a slate gray color called blue and bb produces splashed white. A second gene controls comb shape, with the dominant gene R producing a rose comb and r producing a single comb in the F2 generation what fraction of the offspring will be black with rose comb?
Roan cattle are the heterozygous hybrids of a cross between a white bull and a red cow. If a roan bull were crossed with a red cow, their offspring would should which of the following ratios?
1 red: 1 roan
If a child belonged to blood type O, he or she could Not have been produced with which set of parents?
Type AB mother and type O father.
How is energy and electrons carried from the light carried from the light-dependent reaction to the light independent reaction?
The electrons and energy are carried by NADPH, and ATP respectively.
which of the following are the primarily cellular assembly sites for the production of proteins?
Which of the follow are the primary cellular sites for the recapture of energy from carbohydrates?
Which of the following contain enzymes and are the main organelles of intracellular digestion?
In contrast to the membrane of the nucleus, the double membrane of a mitochondrion
creates two compartments.
Which of the following junctions permit(s) cytoplasmic interconnections between cells?
gap junctions, plasmodesmata, and adhering junctions.
Four of the five statements listed below are portions of a well-known theory. Select the exception.
All cells have a nucleus
In the bonding of two nucleotides:
hydrogen bonds are used, adenine and thymine bind together, purines bind with pyrimidines, double-ring nitrogenous bases connect to single-ring bases.
Movement of molecules in an electrophoretic experiment is based on:
the size and charge of the molecules.