Chapter 3: Protein Synthesis

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[Lavi]

Hello,

Q7 from the chapter review- Why is RNA considered non-genetic material?

7) In the experiment described in the passage, which of the following materials in the germ plasm would likely be most functional in inducing germ cell function?

A) Nuclear DNA.
B) Mitochondria.
C) RNA and protein molecules.
D) Microtubules.

Your Answer: B
Correct Answer: C

Explanation: P3, S5
The passage states that non-genetic material in the germ plasm is responsible for germ cell formation. This rules out nuclear DNA as an option. Mitochondria (energy) and microtubules (structural) are unlikely answers as they have very limited roles to actively change their outside environment. RNA and protein molecules can actively change the environment around them by aiding in the production of proteins, through functioning as enzymes (catalysing reactions), as structural proteins, etc. Thus they are the most likely to induce germ cell function.

Thank you

[goldstanda3269]

Hello,

Q7 from the chapter review- Why is RNA considered non-genetic material?

"Gene/genetic material" is more likely to be referring to DNA.

http://www.dictionary.com/browse/genetics

"Every living thing contains the genetic material that makes up DNA molecules."

[FranaB]

Hi,
I've found an error in the questions:

20) The experiments provide the most support for which of the following statements?

A) Aβ formation is triggered by Bax expression.
B) Overexpression of Bcl-2 leads to apoptosis.
C) Bax expression is induced by Aβ formation.
D) E2 increases mitochondrial Bcl-2 expression.

Result: Your answer is wrong.
Your choice: D Correct choice: C

Explanation: From Figure 3, we see that E2 alone increases relative Bcl-2 expression in the mitochondria by 1.5-fold, meaning answer choice D is correct.

Answer choice A is incorrect, as there is no indication in the passage or experimental results that Aβ is triggered by Bax expression. Answer choice B is incorrect for two reasons: firstly, the passage says that Bcl-2 is an anti-apoptotic protein, and secondly, if E2 induces Bcl-2 expression (Figure 3), we can conclude that this also results in a decrease in the incidence of apoptosis in cells exposed to Aβ (Figure 2). Answer choice C is incorrect as well, because Figure 4 shows that Bax is expressed even in cells that have not been exposed to Aβ.



I chose answer D, and the explanation states "answer choice D is correct", yet it is saying that the correct choice is C?

[goldstanda3269]

I chose answer D, and the explanation states "answer choice D is correct", yet it is saying that the correct choice is C?

You are correct. The explanation pointed to D, the answer you chose, but there was a programming error which has now been corrected. Thank you for bringing it to our attention.

[AlexGM]

Hi, is it just me, or the descriptive passage for page 4 of this chapter's questions contradicts itself?

Paragraph 2 seems to make the point that "more ATK2" -> "more GLI1":
[quote]Gli1 is downstream of the AKT signaling pathway, a signal transduction pathway that promotes cell growth and survival in response to extracellular signals. Stimulation by a variety of growth factors can trigger the pathway, leading to the activation of AKT. The overexpression of AKT's many isoforms, including AKT2, have been linked to the progression of several cancers such as neuroblastoma.[/quote]

However, if I understand figure 1 correctly, experiment 1 seems to show the exact opposite. And experiment 2 contradicts it outright.

[goldstanda3269]

Hi, is it just me, or the descriptive passage for page 4 of this chapter's questions contradicts itself?
...

However, if I understand figure 1 correctly, experiment 1 seems to show the exact opposite. And experiment 2 contradicts it outright.

Exactly!

Your conclusion is correct and is expressed in question 14.

Believe it or not, decades ago with the rise of a lot of blood testing, the medical community linked low sodium with high blood pressure and prescribed salt to those patients. People died until the data showed that the issue was more complicated. Paragraph 2 describes the link with AKT and cancer. The experiments try to clarify whether one of the forms of AKT (perhaps it is AKT1?) is the one responsible for neuroblastoma.

[penguin7]

If strain Q has 2 mutations in the synthesis pathway, would it not accumulate citrulline as well?

[goldstanda3269]

If strain Q has 2 mutations in the synthesis pathway, would it not accumulate citrulline as well?

Assuming this is about Chapter 3, Question 7:

Citrulline cannot accumulate in the strain Q double mutation because there cannot be any production of citrulline due to the argF mutation. In order to accumulate, the substance must be produced with no chance of the next step in the production working.

[goldstanda3269]

If strain Q has 2 mutations in the synthesis pathway, would it not accumulate citrulline as well?

Assuming this is about Chapter 3, Question 7:

Citrulline cannot accumulate in the strain Q (double mutation) because there cannot be any production of citrulline due to the argF mutation. In order to accumulate, the substance must be produced with no chance of the next step in the production working.