Biochemistry Part I questions Help Please

[drfun]

BioChem

Each of the following polymers is correctly paired with an activated precursor of the polymer EXCEPT one. Which one is the exception?

A. Sucrose – Dextran
B. Glucose-Glycogen
C. Sucrose-Mutan
D. UDP-glucose-Glycogen
E. Sucrpse-Levan

Which of the following spans the cell membrane and anchors cells to the extracellular matrix?

A. Keratin
B. Integrin
C. Collagen
D. Chondroitin
E. Hyaluronate

Which of the following best describes the function of allopurinol?

A. promotes conversion of uric acid to DNA
B. allosterically interferes with gluathione reductase
C. promotes excretion of uric acid
D. competitively inhibits xanthine oxidase

Which of the following characterizes the generator potential of a receptor?

A. an all-or-none response
B. propogated in a non-decremental manner
C. universally present in all nerve tissues
D. graded according to the strength of the stimulus

DNA that is complimentary to mRNA can be made using which of the following?

A. a plasmid
B. DNA ligase
C. A retrovirus
D. RNA polymerase
E. Reverse transcriptase

A urine sample of pH 5.7 has a hydrogen-ion concentration of approx?

A. 2 x 10(-4) M
B. 2 x 10(-5) M
C. 2 x 10(-6) M

For which is the first group of the following pairs more likely to be localized on the surface of a globular protein than the second group of the pair?

A. –CONH2 -COO-
B. –CH3 CH(CH3)2
C. CH2OH -NH4
D. –CH3 -CH2OH
E. –CH2Sh -COO-

Choose the pair that correctly identifies where –CO2 is produced and O2 is consumed:

Produced Consumed
A. Ribosomes ATP synthesis
B. The Krebs Cycle cytochrome oxidase
C. ATP synthase The Krebs Cycle
D. Cytochrome oxidase The Krebs Cycle
E. Cytochrome oxidase ATP synthase

One strand of DNA double helix is 20 percent A, 30% T, and 40% C. What is the percentage of C on the other strand?

A. 10%
B. 20
C. 50
D. 80
E. 90

Which of the following tissues uses Ketone bodies as a major fuel in the resting state?

A. Brain
B. Liver
C. Muscle
D. Adipose
E. Red Blood Cells

Which of the following best describes GTP-binding (G-proteins)?

A. They are important components of steroid hormone signal transduction
B. They catalyze the reaction that produces diacylglyerol
C. They are lightly bound to adenylate cyclase
D. They usually inactivate protein kinase C
E. They are left inactivating

Which of the following serves as the principle relay station in the brain?

A. thalamus
B. cerebellum
C. basal ganglia
D. sensory cortex
E. substantia nigra

What is the net charge on glutamic acid at a pH of 1?

A. +2
B. +1
C. 0
D. –1
E. –2


Skeletal muscle blood flow is autoregulated by?

A. epinephrine
B. axon reflexes
C. acetylcholine
D. spinal reflexes
E. local metabolites

Complimentary DNA (cDNA) libraries include:

A. all the DNA in the genome
B. only genes with palidromic sequences
C. only the genes that were transcribed into mRNA
D. single stranded DNA synthesized by reverse transcription

Which of the following occurs when venous blood reaches the lungs?

A. movement of chloride ions from erythrocyte to plasma
B. movement of bicarbonate ions from erythrocyte to plasma
C. movement of hydrogen ions from hemoglobin to plasma
D. movement of bicarbonate ions from plasma to the erythrocyte

Glucose is reabsorbed by:

A. facilitated diffusion in the proximal segment only
B. primary active transport in the proximal tubule only
C. co-transport with amino acids in the prox. Tubule only
D. secondary active transport in the prox. Tubule only

In which of the following conditions is oxygen partial pressure low in arterial blood:

A. anemia
B. polyvythemia
C. pulmonary AV shunt
D. hypovolemia due to hemorrhage

Which of the following explains why the digestive action of salivary amylase continues for some time after swallowing:

A. Gastric HCl increases digestive action of amylase
B. Gastric mucin lubricates the bolus and assists amylase activity
C. The amylase inside the bolus is protected from the inactivating action of gastric HCl
D. Water absorption by the stomach concentrates amylase and makes its action more effective
E. Contractions of the stomach distribute amylase more evenly throughout the bolus

---

Members don't see this ad.

 

[rtvj]

here r some of the answers




Which of the following best describes the function of allopurinol?

A. promotes conversion of uric acid to DNA
B. allosterically interferes with gluathione reductase
C. promotes excretion of uric acid
D. competitively inhibits xanthine oxidase

Which of the following characterizes the generator potential of a receptor?

A. an all-or-none response
B. propogated in a non-decremental manner
C. universally present in all nerve tissues
D. graded according to the strength of the stimulus

DNA that is complimentary to mRNA can be made using which of the following?

A. a plasmid
B. DNA ligase
C. A retrovirus
D. RNA polymerase
E. Reverse transcriptase


Choose the pair that correctly identifies where –CO2 is produced and O2 is consumed:

Produced Consumed
A. Ribosomes ATP synthesis
B. The Krebs Cycle cytochrome oxidase
C. ATP synthase The Krebs Cycle
D. Cytochrome oxidase The Krebs Cycle
E. Cytochrome oxidase ATP synthase



Which of the following best describes GTP-binding (G-proteins)?

A. They are important components of steroid hormone signal transduction
B. They catalyze the reaction that produces diacylglyerol
C. They are lightly bound to adenylate cyclase
D. They usually inactivate protein kinase C
E. They are left inactivating



Skeletal muscle blood flow is autoregulated by?

A. epinephrine
B. axon reflexes
C. acetylcholine
D. spinal reflexes
E. local metabolites

Complimentary DNA (cDNA) libraries include:

A. all the DNA in the genome
B. only genes with palidromic sequences
C. only the genes that were transcribed into mRNA
D. single stranded DNA synthesized by reverse transcription

Which of the following occurs when venous blood reaches the lungs?

A. movement of chloride ions from erythrocyte to plasma
B. movement of bicarbonate ions from erythrocyte to plasma
C. movement of hydrogen ions from hemoglobin to plasma
D. movement of bicarbonate ions from plasma to the erythrocyte

Glucose is reabsorbed by:

A. facilitated diffusion in the proximal segment only
B. primary active transport in the proximal tubule only
C. co-transport with amino acids in the prox. Tubule only
D. secondary active transport in the prox. Tubule only

In which of the following conditions is oxygen partial pressure low in arterial blood:

A. anemia
B. polyvythemia
C. pulmonary AV shunt
D. hypovolemia due to hemorrhage

pls correct if wrong!

rtvj

 

[rtvj]

One strand of DNA double helix is 20 percent A, 30% T, and 40% C. What is the percentage of C on the other strand?

A. 10%
B. 20
C. 50
D. 80
E. 90

 

[anjali_45]

Which of the following spans the cell membrane and anchors cells to the extracellular matrix?

A. Keratin
B. Integrin
C. Collagen
D. Chondroitin
E. Hyaluronate
choice B
Which of the following best describes the function of allopurinol?

A. promotes conversion of uric acid to DNA
B. allosterically interferes with gluathione reductase
C. promotes excretion of uric acid
D. competitively inhibits xanthine oxidase
choice D

Which of the following explains why the digestive action of salivary amylase continues for some time after swallowing:

A. Gastric HCl increases digestive action of amylase
B. Gastric mucin lubricates the bolus and assists amylase activity
C. The amylase inside the bolus is protected from the inactivating action of gastric HCl
D. Water absorption by the stomach concentrates amylase and makes its action more effective
E. Contractions of the stomach distribute amylase more evenly throughout the bolus
I think choice A becos the hcl is being secreted so as long there is stimulus there is saliva excretion hence amylase action
but i am not sure

 

[drfun]

Thanks a lot rtvj.
Are you going to take part 1 in July11?

Dr.fun

 

[drfun]

Thanks Anjali45

 

[Inshaa]

it would be highly appericiated if someone who is confident of their answer can spare some time to quote the answers,thx
1)5-fluorouracill interfers with synthesis of which of following
a) adenylate
b)guanylate
c)cytidylate
d)thymidylate


2)fingers and other extremites are particularrly susceptible to frostbite boz
a)they have less dense capillary beds than surrounding tissues
b)the body shunt nlood flow away from these areas to maintain core temperature
c0they have little adipose tissue to insulate them for heat conversation
d)the surface areas to volume ratio is lowerin neighboring tissuse facilitating heat loss

3)atropine prevents the secretion of saliva resulting from stimulation of chorda tympani boz it
a)denatures the salivary gland protiens
b)prevents the actionof acetylcholine on the secreting cells
c)prevents release of acetylcholine by parasympathetic postganglionic fibres
d(prevents release of acetylcholine by sympathetic postganglionic fibres
E)prevents release of acetylcholine in autonomic ganglia

thx

Thanks Anjali45

 

[rtvj]

some of the answers

it would be highly appericiated if someone who is confident of their answer can spare some time to quote the answers,thx
1)5-fluorouracill interfers with synthesis of which of following
a) adenylate
b)guanylate
c)cytidylate
d)thymidylate


3)atropine prevents the secretion of saliva resulting from stimulation of chorda tympani boz it
a)denatures the salivary gland protiens
b)prevents the actionof acetylcholine on the secreting cells
c)prevents release of acetylcholine by parasympathetic postganglionic fibres
d(prevents release of acetylcholine by sympathetic postganglionic fibres
E)prevents release of acetylcholine in autonomic ganglia

thx

 

[thaizemelo]

2)fingers and other extremites are particularrly susceptible to frostbite boz
a)they have less dense capillary beds than surrounding tissues
b)the body shunt nlood flow away from these areas to maintain core temperature
c0they have little adipose tissue to insulate them for heat conversation
d)the surface areas to volume ratio is lowerin neighboring tissuse facilitating heat loss


Asw; letter A