AP
The atomic mass of carbon is 12. How many protons are in this atom?
6
a sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA.
Anticodon
Which of the following would be regarded as an organic molecule?
CH4
The structural and functional units of organisms are the
Cells
Using an electron microscope, the cell reveals microtubules arranged to form a hollow tube. This structure is a:
Centriole
a sequence of three nucleotides which together form a unit of genetic code in a DNA or RNA molecule
Codon
Which reactions will usually be irreversible regarding chemical equilibrium in living systems
Complete glucose decomposition
Regarding a negative feedback loop, the part of the control loop responsible for analyzing and integrating information from the sensors found around the body is the:
Control Center
Which of the following statements is MOST correct regarding the intracellular chemical signals known as second messengers?
Cyclic AMP and calcium may be second messengers.
Select the most correct statement regarding nucleic acids.
DNA is a long, double-stranded molecule made up of A, T, G, and C bases.
The random movement of molecules resulting in net movement of substances from an area of high concentration to an area of low concentration is called:
Diffusion
_____ requires a carrier molecule, but does not use cellular energy (ATP).
Facilitated diffusion
The principle function of the _____ is to process, sort, and deliver proteins and lipids to the plasma membrane, lysosomes, and secretory vesicles.
Golgi Apparatus
Which of the following are a characteristic of an enzyme?
Has a specific active site which binds to one substrate and speeds up the rate of reaction
The umbilicus is _____ to the thoracic region.
Inferior
Which of the following is true of the plasma (cell) membrane?
It is a selectively permeable membrane that encloses the cell
Which statement is most correct of homeostatic imbalance?
It is considered the cause of most diseases.
When a cell is placed in a hypertonic solution:
It shrinks
When a neutral atom becomes a cation (i.e., positive ion), it has: (an example is a calcium ion Ca2+)
Lost electrons
Negative-feedback mechanisms
May have a receptor, a control center, and an effector
A 65-year old patient presents with symptoms that include loss of motor control, muscle weakness and pain, gastrointestinal disorders and swallowing difficulties, and extreme fatigue. The organelle that is most likely failing in this individual?
Mitochondria
A red blood cells is placed in pure water would:
Swell and burst
Which of the following statements is correct regarding diffusion?
The greater the concentration of gradient, the faster the rate of diffusion.
The more alkaline a solution is:
The higher the pH
Which statement is the MOST correct regarding transcription/translation?
The nucleotide sequence in a tRNA anticodon is an exact copy of the DNA triplet that coded for it except that uracil is substituted for thymine.
Which body cavity contains the pleural and pericardiac cavities?
Thoracic Cavity
The process by which DNA is copied to RNA is called
Transcription
RNA is used to produce proteins is called
Translation
If a tRNA had an AGC anticodon, it could attach to a(n) _________________ mRNA codon.
UCG
For (net) diffusion to occur from point A to point B there must be:
a concentration difference between A and B.
A gene can best be defined as:
a segment of DNA that carries the instructions for one polypeptide chain
A solution that has a pH of 2 could best be described as being:
acidic
Which of these is are a connective tissue?
adipose tissue, blood, and areolar tissue
If an atom were to have two protons, then it would:
be very stable
In redox reactions:
both decomposition and electron exchange occurs
Cells are composed mainly of:
carbon, hydrogen, nitrogen, oxygen
If cells are placed in a hypertonic solution containing a solute to which the membrane is IMPERMEABLE, what could happen?
cells lose water and shrink
The differences between mixtures and compounds include:
chemical bonding does not occur between the components of a mixture
A vertical section through the body, dividing it into anterior and posterior, is called:
frontal
Carbohydrates are stored in the liver and muscles in the form of:
glycogen
Salts are ALWAYS:
ionic compounds
The parietal pleura would represent a serous membrane ________.
lining the thoracic cavity
The abdominal cavity contains the:
liver, stomach, spleen, small intestine, and most of the large intestine
Which structures are fingerlike projections that greatly increase the absorbing surface of cells?
microvilli
Which of the following is a function of the plasma membrane protein?
molecular transport through the membrane
Carbohydrates are comprised of:
monosaccharides
Passive membrane transport processes include:
movement of a substance down its concentration gradient
Isotopes of the same element have the same:
number of protons but different number of neutrons
Which of the following cavities are lined by serous membranes?
pelvic cavity, pleural cavity, abdominal cavity, and pericardial cavity
Some hormones enter cells via:
receptor-mediated endocytosis
A chemical reaction in which bonds are broken is associated with:
release energy
The coiling of the protein chain backbone into an alpha helix is referred to as the:
secondary structure
If a cell lacked ribosomes, it could not:
synthesize protein
The RNA responsible for bringing the amino acids to the "factory" site for protein formation is the
tRNA
DNA replication:
takes place during interphase of the cell cycle
The plasma membrane is:
the phospholipid bilayer surrounding the cell
The speed or rate of a chemical reaction is influenced by all of the following EXCEPT
the presence or absence of carbon