1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
blsea [12.9K]
3 years ago
9

If 20% of a DNA sample is made up of thymine, T, what percentage of the sample is made vo

Biology
2 answers:
Ksenya-84 [330]3 years ago
6 0

Answer:

B. 30%

Explanation:

DNA has four type of nitrogenous bases in its nucleotides named as adenine, thiamine, cytosine and guanine and the abbreviations for these bases are A, T, C and G respectively. DNA is a double stranded bio molecule and the nucleotides of both the strands of DNA are joined with each other with the help of either double bonds or triple bonds which exist between the nitrogenous bases of its nucleotides. There are two type of bases, purines and pyrimidines. Adenine and guanine are purine bases while cytosine and thiamine are pyrimidine bases.

Chargaff's base pair rule says that the ratio of purine bases with respect to pyrimidine bases must be 1:1 ratio. It can be possible only if a purine base pairs with pyrimidine base of the adjacent DNA helix. So, adenine which is a purine always pairs up with thiamine which is a pyrimidine with the help of two hydrogen bonds while guanine being a purine always pairs up with cytosine which is a pyrimidine with the help of three hydrogen bonds. It simply means that a DNA molecule will have as many adenine as many there are thiamine. Also, for the same reason there will be as many cytosine as many there are guanine.

So, 20% of T means same amount of A which is 20%. Hence, A and T will together form 20% + 20% = 40% of the sample.

In the remaining 60% sample the amount of C and G is equal that means it will have 30% C and 30% G.

So, the answer is 30% C or cytosine.

Brut [27]3 years ago
3 0
B. 30% because it was in the internet and i just gave it to you
You might be interested in
The sum of all of the chemical reactions that occur in a cell collectively are called:
artcher [175]
These reactions are METABOLISM.
4 0
3 years ago
1) A specialized function shared by the many cells lining the lungs and the lumen of the gut isA) decreased oxygen demand due to
gogolik [260]

Answer:

B) increased exchange surface provided by their membranes

Explanation:

Alveoli are tiny air sacs that are responsible for exchanging oxygen (O2) and carbon dioxide (CO2) in the lungs. Alveoli have elastic fibers in order to expand and recoil depending on the volume of air breathed in. The alveolar epithelial cells (pneumocytes) may adopt a shape that serves to increase the surface area of gas exchange. On the other hand, intestinal epithelial cells have microvilli, which are microscopic projections in the plasma membrane. Microvilli serve to increase the cell's surface area, thereby facilitating the absorption of nutrients and water.

4 0
3 years ago
Read 2 more answers
Which of these describes a situation where natural selection could lead to evolution?
Gennadij [26K]

Answer:

B. Predation removes slower antelope from the herd.

Explanation:

Natural selection is defined as the differential survival and reproduction of individuals due to differences in the physical characteristics.

A predator-prey relationship results in a very fast-slow dynamical system for rapid predator evolution.

Predation removes slower antelope from the herd and hinders passage of the slow trait to offsprings. The ones who are fast reproduce and give birth to other fast animals.

5 0
3 years ago
A nucleotide is....
Julli [10]
A nucleotide is DNA
(Also RNA)

Hope that helped! :)
8 0
3 years ago
Help!!! I need the answers ASAP!
amm1812
D1, A2, B3, C4, and sicnce 5 and E are left i guess they mach up, but it dont think that water is a wast.. but the other one r right
6 0
3 years ago
Other questions:
  • What set of characteristics do living organisms such as birds, trees, and bacteria all have that distinguish them from nonliving
    10·1 answer
  • humans grow to a certain height and then do not grow any taller. do plants grow in the same way? how do plants get taller? expla
    5·1 answer
  • Ever since Allison vomited all over her boyfriend after she ate a chicken salad sandwich that had been sitting in the sun all da
    7·1 answer
  • Which statement indicates that the patient who is taking an adrenergic-blocking drug understands the importance of avoiding othe
    5·1 answer
  • How do animals store energy
    12·2 answers
  • Why temperature above 30 have different effects on immobilized enzyme and enzyme in solution​
    15·1 answer
  • How can we learn about what the buffalo are eating? What kind of data do we need?
    8·1 answer
  • Human blood type AB is a trait that is the result of what pattern of inheritance?
    9·1 answer
  • DNA ___________ is important because it ensures that when a cell divides, the two resulting cells have the same genetic code. Pl
    8·1 answer
  • During the elongation phase of translation, which site in the ribosome represents the location where a codon is being read?.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!