Bio/Biochem

Question 1

the sequence in which information travels from the CNS to the periphery.

Answer 1

cerebral cortex, spinal cord, efferent neurons, interneurons, motor neurons, muscle tissue

Question 2

The catecholamines are

Answer 2

neurotransmitters dopamine, norepinephrine, epinephrine which are all produced from the precursor L-DOPA.

Question 3

Parkinsons is associated with

Answer 3

Low Dopamine levels in the CNS. DAMAGE OF DOPAMINERGIC neurons in the substantia nigra

Question 4

Is Thyroid hormone a peptide or a steroid hormone

Answer 4

It’s a sneaky bastard. It’s a goddamn steroid hormone

Question 5

types of genetic mutation inheritance are

The twotypes of mutations are

Answer 5

autosomal or sex-linked. Most sex-linked mutations are x-linked since there are fewer alleles on the y-chromosome.

Question 6

Inheritance diseases that skip a generation are always

If a phenotype skips a generation then it must be

Answer 6

recessive

Question 7

x-linked inheritance is mostly

Answer 7

recessive (they affect males more often)

Question 8

Penetrance

Answer 8

yes or no question. What is the likelihood that the dominant phenotype will manifest. In the case of the BRCA gene mutation, the likelihood is 80% likelihood of getting breast cancer.

Question 9

expressivity

Answer 9

to what degree is a phenotype expressed or manifests

Question 10

Disulfide bonds are formed btn the Ss of cysteine (C) amino acids. The 2 cysteins drop the Hs and form a bond S-S. which STRUCTURE CHARACTERIZE THIS THESE bonds?

Answer 10

Tertiary

Question 11

The lac operon is negative inducible

Answer 11

this implies that it is only induced to metabolize lactose when it is present. Otherwise the repressor is always bound to the operator sequence to prevent transcription of lac proteins.

Question 12

The Tryp operon is negative repressible

Answer 12

It is always transcribing proteins until a certain condition causes it to repress transcription.

Question 13

Large proteins travel faster during column chromatography

Answer 13

They elute first and quickly

Question 14

Le chatlier. increasing volume(decreasing pressure) of reaction will cause a shift to

Answer 14

whichever side has the most gas molecules.

Question 15

Le chatlier. FOR POSITIVE delta H, increasing temp will cause shift to

Answer 15

products side

Question 16

le chatlier. Increasing temp when delta H is negative will

Answer 16

shift reaction towards reactants side

Question 17

Which of the keto-enol tautomeric isomers is favored at room temperature

Answer 17

The keto form

Question 18

Parathyroid Hormone

Answer 18

increases blood calcium by triggering osteoclast activity which breaks down bone to release calcium mineral into blood stream.

Question 19

Amides unlike amines are not basic

Answer 19

Yup, Yup

Question 20

Viruses are obligate intracellular parasites, which means that they must hijack host cells to replicate. The genetic material of viruses can be in the form of either single-stranded or double-stranded DNA or RNA. Single-stranded RNA viruses are further subdivided into positive-sense and negative-sense viruses. Positive-sense RNA viruses contain mRNA that can immediately be translated by the cell. In contrast, negative-sense RNA viruses contain RNA that is complementary to mRNA, meaning that mRNA must be synthesized by an enzyme known as RNA replicase that is carried in the virion.

Bacteriophages are viruses whose host cells are bacteria. Instead of entering the cell completely, they inject their genetic material into their host through a syringe-like structure known as a tail sheath. Retroviruses are a distinct class of single-stranded RNA viruses, including HIV, that use an enzyme known as reverse transcriptase to synthesize DNA from their RNA genome.

Bacteriophages have two distinct life cycles: lytic and lysogenic. During the lytic cycle, the bacteriophage essentially works to replicate at full speed, making full use of the host cell’s machinery. Eventually, the host cell is filled with virions to the point that it bursts or lyses, and a tremendous number of new virions spill out into the environment. Alternately, in the lysogenic cycle, bacteriophages can integrate themselves into the host genome, at which point they are referred to as a prophage or a provirus. In response to environmental signals, the prophage can re-emerge from the host genome and resume a lytic cycle. Non-bacteriophage viruses (e.g., those that infect humans) can exhibit a dormant stage that is similar to the lysogenic cycle. Examples of viruses with a prominent dormant stage include HIV and herpesvirus.

Answer 20

The passage states that HERVs, or human endogenous retroviruses, arose through the integration of retroviral material into the genome. It also mentions that HERVs are able to perform reverse transcription, a process that requires the enzyme reverse transcriptase. This enzyme catalyzes the production of DNA from an RNA template. Reverse transcriptase thus must have DNA polymerase activity, since it builds a new DNA strand; it is also RNA-dependent, since it reads an RNA template.