Cells that surround melanocytes may contain more melanin than the melanocytes because of the process of _____.
he color of red hair is due to _____.
he most easily regulated loss of heat through the skin is by _____.
thinner in areas receiving greater friction and use
Which of these phrases does not characterize the dermis?
stratum basale of the epidermis
Hairs arise from which layer of the skin?
Persons who remain indoors frequently may have a higher risk of developing a malignant melanoma than those who are highly exposed to sunlight because of their work or other reasons.
Studies have shown that_____to high intensity sunlight, such as during some vacations, may cause cancer more likely than a constant level of daily exposure.
Excessive hair growth on regions of the body is alopecia.
_____is a term which indicates a condition of hair loss or baldness and can occur on any part of the body.
Sebaceous glands are always associated with each hair follicle.
_____can open directly onto the surface without association with hair follicles, such as in the genitals or lips.
Heat exhaustion occurs when the body undergoes excessive sweating on hot, humid days.
_____occurs when the body is unable to eliminate excess body heat fast enough; it includes cramping and fatigue.
The white blood cells secrete interleukins, which are known to block the causes of fevers.
_____is a class of compounds that cause many reactions including the development of a fever, by stimulating the hypothalamus.
The cells in the epidermis are only comprised of squamous epithelial cells.
Cells in the deeper layers of the_____are cuboid. However the epithelium is classified as squamous because of the shape of the surface cells.
Penicillin acts to render bacterial cells nonviable because it damages their _____.
_____interferes with the synthesis of cell walls by bacteria and in this way blocks their reproduction.
Most reactions that produce energy in a cell utilize _____ as the main reaction type.
The most significant function of proteins is to produce _____.
A gene instructs an organism to produce a/an _____.
The fundamental units found in DNA, RNA and ATP are _____.
_____contains the sugar ribose but cannot have the base thymine which is found only in DNA.
The amino acids are transported to the place where they will be assembled into proteins by _____.
lower the energy of activation needed to start the reaction
Enzymes function in chemical reactions to ____________________.
phosphorylation of ADP to form ATP
Most of the readily-available energy stored in ATP is stored during the ________________.
energy from ATP is transferred to intermediates along the pathway to drive the reactions
The first several steps of glycolysis are considered the energy-investment steps because ______________.
Carbon dioxide and hydrogen atoms are released, and two molecules of ATP form.
What occurs during the citric acid cycle?
_____is a substrate.
pH of 7.4
The following factors will decrease the function of most enzymes except which one?radiation,50 degrees C,pH of 7.9 or_____
Energy metabolism is an expression that can be used to mean the same as _____.
Carbohydrates in the diet are changed into glucose by a process of _____.
The following are end products of the Kreb cycle except which one?
are in the Kreb cycle
The following are true of NAD and FAD except which statement?are vitamin derivatives, contain nucleotides, transport hydrogen,_____
The presence of _____ is an indication that glucose has been completely oxidized.
The most common form of a lipid that is used or burned for energy is called a _____.
The metabolically most active organ in the body probably is the _____.
The following are DNA bases except which one?
A genetic code is a sequence of _____.
A set of nucleotides called the _____ in RNA recognizes the nucleotide genetic codes of DNA.
What is the anticodon for DNA base sequence ATG?
The first step in the utilization of amino acids for energy is ________ which occurs in the liver.
The production of mRNA from a DNA template is termed _____.
The base sequence termed the anticodon is found on molecules of _______.
Enzymes are catalysts that alter chemical reaction rates by chemically combining with the substrate
The bond that is formed between the______and its substrate is actually physical and not chemical in nature; this must be true because the enzyme can be recovered unaltered after the reaction.
There are about 20 amino acids that are significant for humans but, only about eight (in adults) must be obtained directly from the diet since the liver is capable of synthesizing and converting other molecules into various amino acids.
There are about 20______that are significant for humans but, only about eight (in adults) must be obtained directly from the diet since the liver is capable of synthesizing and converting other molecules into various amino acids.
Most of the ATP energy in the metabolism of glucose is derived from the Kreb's cycle
electron transport chain
Most ATP comes from the reduction of oxygen in the______ .
An ATP molecule consists of an adenine, a ribose, and five phosphates.
ATP stands for adenosine triphosphate. The tri- means______ .
none of the above
Which of the following are limitations of DNA polymerase?it can only add bases to the exposed 5' end of a pre-existing strand, it can only replicate the leading strand, it can only replicate the lagging strand
The enzyme ________ unzips and unwinds the DNA molecule.
the leading strand is replicated continuously, while the lagging strand is replicated discontinuously
Which of the following statements about DNA replication is TRUE?
DNA replication results in two identical daughter molecules each consisting of one old (original) strand and one newly-synthesized strand.
The point where separation of the DNA occurs is called the replication fork.
in the cell membrane.
The electron transport chain in bacteria is located...
During aerobic respiration, the last carrier protein transfers a pair of electrons to...
utilize the energy of the proton motive force to convert ADP to ATP.
The function of the enzyme ATP synthase is to...
Electrons enter the electron transport chain when NADH transfers them there along with protons in the form of hydrogen.
The electron transport chain consists of a series of membrane-bound carriers that shuttle protons and electrons to NADH.
Which of the following binds to the active site of an enzyme?
E + S -> E-S -> E-P -> E + P
Which of the following correctly represents the mechanism of enzyme function?
An enzyme can only bind one reactant at a time.
An enzyme speeds up a chemical reaction in the cell, but can only be used once.
In glycolysis, glucose is converted to
2 NADH and 2 ATP.
The NET result of a single glycolysis run is the formation of
Under anaerobic conditions, the end-product of glycolysis is converted to
Under aerobic conditions, the end-product of glycolysis is further reduced to yield more ATP.
1 ATP, 3 NADH, and 1 FADH2.
A single "turn" of the Krebs cycle will yield
2-carbon molecule to a 4-carbon molecule.
The initial reaction of the Krebs cycle involves the addition of a
The Krebs cycle occurs in the mitochondrion.
A single "turn" of the Krebs cycle involves four different decarboxylation reactions.
proteins from mRNA
Translation is the synthesis of
the tRNA that was in the P site moves into the E site
Which of the following occurs as the ribosome shifts down the mRNA by a distance of three nucleotides?
Translation is terminated when a stop codon is presented at the ________ site.
The first amino acid enters through the A site.
he codon of tRNA is complementary to the anticodon of mRNA.
The segment of the DNA molecule where messenger RNA synthesis begins is called the...
The complimentary messenger RNA strand that would be synthesized from the DNA base sequence of CTGAC would be...
) transcription terminator
The name of the structure that causes the synthesis of RNA to cease is called the...
The synthesis of messenger RNA is called translation.
Synthesis of a new strand of messenger RNA is in the 5' to 3' direction.
The deeper layers of the skin are comprised of _____ tissue cells.
Which of the following cells can divide in the adult?
An exocrine gland that loses small parts of its cell body during secretion, as is the case for the mammary gland, is further classified as a(n) ____________ gland.
transmitting nervous impulses
Neuroglial cells help neurons in each of these ways, with the exception of _______________.
Blood is classified as a _____ tissue because it has cells embedded in a matrix.
One of the differences between cartilage and bone is that bone is a living tissue with a calcium matrix and a rich vascular supply.
The intervertebral disks are comprised mainly of elastic cartilage to allow for pliability.
The oviducts are lined with ciliated pseudostratified columnar epithelial cells which help propel the egg cells.
The oviducts contain ciliated epithelia, however it is_____ .