April 20, 2014

Homework Help: Biology

Posted by Jessie on Thursday, December 6, 2012 at 6:12pm.

For questions 1 and 2 use the table in Figure 12-3 to help you answer the question.

Nitrogenous Bases

Figure 12-3
1. The table in Figure 12-3 shows the results of measuring the percentages of the four bases in the DNA of several different organisms. Some of the values are missing from the table. Based on Chargafffs rule, the percentages of guanine bases in chicken DNA should be around _____.

(1 point)28.8%

2. Based on Chargafffs rule, the percentage of cytosine in the DNA of the bacterium S. lutea in Figure 12-3 should be around _____. (1 point)26.6%

3. What structural problem prevents adenine from pairing with guanine? (1 point)The bases are both short.
They lack phosphate groups.
They lack the deoxyribose group.
The bases are both long.

4. Rosalind Franklin contributed to the understanding of DNA by _____ (1 point)producing images of DNA molecules using X-rays.
figuring out that DNA strands form a double helix.
conducting experiments that showed which nucleotides are complementary.
finding that DNA was nucleic acid made up of a long chain of individual nucleotides.

5. What is true about the base pairs A-T and G-C? (1 point)They occupy different widths, which allows the DNA molecule to form a helix.
They occupy the same width, which allows the helical radius to remain constant.
They are always present in the same ratios across all species.
They are stabilized by covalent bonds between the bases.

6. Which of the following discoveries provided a critical clue to Watson and Crick in solving the structure of DNA? (1 point)the Hershey-Chase experiment
Griffithfs transformation experiment
Chargafffs base ratios

Miescherfs isolation of DNA

7. A DNA strand with the sequence A-T-T-G-C-T would be complementary to which of the following? (1 point)T-A-T-G-G-A

8. DNA from one species differs from the DNA of another species in its _____. (1 point)base ratios
phosphate groups
all of the above

9. Which of the following shows the correct sequence of events? (1 point)Chargafffs base ratio analysis ¨ Miescherfs isolation of DNA ¨ Franklinfs X-ray diffraction studies
Griffithfs transformation experiment ¨ Chargafffs base ratio analysis ¨ Watson and Crickfs model of DNA
Franklinfs X-ray diffraction studies ¨ Hershey-Chase experiment ¨ Averyfs transformation experiment
Miescherfs isolation of DNA ¨ Franklinfs X-ray diffraction studies ¨ Griffithfs transformation experiment

Answer this Question

First Name:
School Subject:

Related Questions

Math - Use the following table to answer questions. x y 1 7 3 ? ? 11 7 13 ? ? ...
biology yr 12 - please help i have 2 biology questions. identify examples of ...
Mathematics - I have three questions... Okay think of a 1-9 multiplication table...
PLeASE Help - Can someone please take a look at my biology questions I have ...
math plz help - Task 2: Use the table to complete each part. a. Copy the table. ...
AP BIOLOGY - I have a quiz on genetics on friday in AP Biology and I would like ...
biology - please can you answer the following questions in as much dephth as ...
Biology - when might you use the "poor-quality website" in an academic ...
statistic - Quiz has 6 questions. Each question has five possible answers, only ...
Stats - Richard has just been given a 4-question multiple-choice quiz in his ...