EXAM 1 Flashcards
Electronegativity is a measure of an atoms ability to attract a shared electron pair when it is participating in a covalent bond with another atom.
True
The production of a large molecule from smaller subunits is referred to as a catabolic reaction.
False; anabolic reaction
An enzyme is a biological carbohydrate-based catalyst.
False; protein-based
Cells can control metabolic processes by restricting the location of enzymes and enzyme complexes within the cell.
True
Aerobic cellular respiration requires that oxygen be present.
True
Cellular respiration results in the relatively rapid, uncontrolled release of energy from a molecule of glucose to produce ATP for use by cells for various function.
False; relatively slow, controlled
Enzymes lower activation energy.
True
Ribosomes move along mRNA in a 5’–>3’ direction.
True
Some restriction endonucleases make zigzag cuts in double-stranded DNA leaving blunt cells.
False; leaving sticky ends
Contractions that increase in strength during pregnancy are an example of a negative feedback mechanism.
False; positive feedback mechanisms
Kidney’s remove waste, balance blood pH, and maintain water balance.
True
Wastes are filtered from the blood by the kidneys and conducted to the urinary bladder by the urethra.
False; ureter
A cross section of the kidney shows an oiter layer called the medulla, an inner layer called the cortex, and a hollow chamber called the renal pelvis.
False; outer layer called the cortex, inner layer called the medulla
When a person sweats and does not drink water, the pituitary gland releases ADH.
True
Insulin is produced in a healthy person when blood sugar is low.
False; blood sugar is high
People with diabetes feel tired because of low levels of glucose in the blood.
False; low levels of insulin
As follicles develop in the ovary, estrogen concentration in the blood decreases.
False; increases
Information from your brain is moved to your leg muscles by motor neurons.
True
Myelin sheath is very important for the transferring of information along the medulla.
False; axon
Electrochemical messages are carried by the movement of ions through the nerve membrane.
True
When the nerve cell is excited, it becomes more permeable to potassium ions than sodium ions.
False; sodium ions then potassium ions
Sharks, snakes, and crocodiles are able to grow new teeth all of their lives. This is considered to be an example of analogous structures.
False; homology
Islands are very important places in which speciation occurs because the populations they contain are spatially isolated from other populations.
True
Over time, the total number of species in existance deos not change.
False; changes
A species is a group of individuals that are reproductively compatible with each other but not with individuals from other groups.
True
The following structural formula is representative of which functional group?
-C=O
\
O
|
Hcarboxyl
An amino acid always has an amino group, as its name suggests. What other group is also present in all amino acids?
a carboxyl group
The hydrolysis (breakdown) of a dipeptide results in the production of which of the following?
Two amino acids
In aerobic respiration, which is a typical oxidation/reduction reaction, the energy…
Required for reduction is the same as that released in oxidation
The key point about oxidation is that it is a process in which….
There is a loss of electrons
Which of the following statements about enzymes is not true?
They will bind their substrate and any isomer of their substrate.
The reactants in cellular respiration, glucose, and oxygen are stable compounds. How do these substances react?
The activation energy is reduced by enzymes.
The following molecules can be found at various stage during cellular respiration:
I. Acetly-CoA
II. Carbon Dioxide
III. Glucose
IV. Glyceraldehyde
V. Pyruvate
Which of the following sequences represents the above molecules in order from the largest to the smallest amount of chemical energy?
III, IV, V, I, II
Glucose, glyceraldehyde, pyruvate, acetyl-CoA, carbon dioxide
Glycolysis can best be described as which of the following kinds of pathways?
Anaerobic and catabolic
Anaerobic respiration is less efficient than aerobic respiration for which of the following reasons?
Less ATP is produced in anaerobic respiration.
The alternate fates of pyruvate in various organisms is primarily due to…
Regenerating NAD+ for further reduction in the cytoplasm.
DNA replication…
Occurs before cytokinesis
DNA is stable because hydrogen bonds are formed between…
Purines and pyrimidines
An enzyme, which excuses a mismatched base in a newly synthesized strand of DNA, is called…
An exonuclease
A section of mRNA 9 codons long would most likely result in the addition of how many amino acids to a growing polypeptide (the stop codon is absent front the section of mRNA)?
9
There are differences in the amino acid sequence of rabbit and frog haemoglobin polypeptides. If mRNA for rabbit red blood cells, and is then placed in frog eggs, the cells will produce rabbit haemoglobin polypeptides. This shows that…
The genetic code and the machinery of translation are substantially the same in widely-different organisms.
Which of the following is true with respect to the lac operon?
The repressor is bound to the operator, except when it is bound to the inducer.
When recombinant DNA is formed, it is necessary to join the sugar-phosphate backbones of the plasmid DNA and the introduced DNA. Which of the following is used to do this?
Ligase
In a hypothetical experiment, human subjects were placed in a room, the temperature of which was higher than body temperature (37 degrees Celsius). At the same time, blood, cooler than 37 degrees Celsius, was infused into the subjects. Choose the correct effect of this experiment on the subjects.
no effect is noticed by the subject.
A family doctor has a patient with the following symptoms: very high blood sugar levels; high sugar level in the urine; is very thirsty; produces large quantities of urine. Which condition should the doctor investigate?
diabetes mellitus
The term used to describe the ability of a living organism to adjust to changing environmental conditions by regulating their internal processes is…
homeostasis
Which of the following analogies would best fit the action of the kidney?
removing all the items and returning what is still useful.
Interneurons are most commonly located in which of the following?
central nervous system
The term phenotype is defined as which of the following?
Observable traits that are formed by the interaction of genes and the environment.
Part of the sides of the DNA ladder
phosphate group
Results in the formation of water
condensation reaction
Class of compounds has the most energy per gram
lipids
Describes the breakdown of macromolecules
catabolic reactions
Class of compounds is principally used for energy
carbohydrates
Forms strong tertiary structures
disulfide bridge
Referring to the Krebs Cycle:
What molecule, derived from glycolysis, is at the start of the cycle?
acetyl-CoA
Referring to the Krebs Cycle:
How many NADH is produced in each turn of the cycle?
3
Referring to ETC and Chemiosmosis:
What are the electron donor molecules at the beginning of the chain?
NADH/FADH2
Referring to ETC and Chemiosmosis:
In what order are the components of the chain arranged?
increasing electronegativity
Referring to ETC and Chemiosmosis:
What moves into the intermembrane space?
protons
Referring to ETC and Chemiosmosis:
What accepts the electrons at the end of the chain?
oxygen
Referring to ETC and Chemiosmosis:
What is the first protein complex of the chain?
NADH dehydrogenase
Referring to ETC and Chemiosmosis:
Where do electrons, protons, and oxygen meet to become water?
cytochrome oxidase
Referring to ETC and Chemiosmosis:
Where do protons re-enter the mitochondrial matrix?
ATP synthase
Process which results in each new DNA molecule consisting of one parental strand and one newly synthesized strand
semi-conservative replication
Unwinds DNA
primase
removes RNA primers
DNA polymerase 1
Short lengths of DNA produced during synthesis of lagging strand.
Okazaki Fragment
New DNA strand which is synthesized continously
leading strand
links sugars and phosphates together
ligase
builds RNA primers
primase
special glial cells
schwann cells
recieve information from sensory receptors or nerve cells
dendrites
extension of the cytoplasm of a nerve cell.
axon
