Get premium membership and access questions with answers, video lessons as well as revision papers.
First of all, those bonds are hydrogen bonds. They are not very strong, and they break as the molecules get farther from each other or at a certain temperature.
Hydrogen bonds form between a hydrogen bond donor and a hydrogen bond acceptor. If we speak for the nucleic acid bases, here are the donors and acceptors:
Between Cytosine and Guanine, there are 3 pairs of acceptor-donor. Hydrogen of NH2 functions as donor, whereas oxygen atom right across functions as acceptor. You can apply the same for the others.
Between Thymine and Adenine, only 2 hydrogen bonds can form as the distance between 2 donors and 2 acceptors allows them to. Remember that, the distance whence a hydrogen bond can form is roughly around 2–4 Angström. Even though I can’t tell at the moment that what distance is between the oxygen and hydrogen of Thymine and Adenine, it is possible to have a look by computational tools. What we know is, they are too distant to form a hydrogen bond. Hence, 2 hydrogen bonds between the two.
Note: It is Thymine, not Thyamine. It may be confused with the vitamin B1, Thiamine.
Hope that helped!
Irene Linah answered the question on January 31, 2019 at 14:59
- Explain the importance of protecting the forest ecosystem with reference to the following:(20 marks)
(a)climate change
(b)biodiversity
(c)biotechnology
(d)water conservation
(e)pollution(Solved)
Explain the importance of protecting the forest ecosystem with reference to the following:(20 marks)
(a)climate change
(b)biodiversity
(c)biotechnology
(d)water conservation
(e)pollution
Date posted: January 16, 2019. Answers (1)
- Distinguish between a weed, Noxious plant and invasive species.(Solved)
Distinguish between a weed, Noxious plant and invasive species.
Date posted: January 11, 2019. Answers (1)
- Give two importance of respiratory quotient(Solved)
Give two importance of respiratory quotient.
Date posted: January 6, 2019. Answers (1)
- Discuss the components of the nephron(Solved)
Discuss the components of the nephron.
Date posted: January 4, 2019. Answers (1)
- Name two classes of phylum arthropoda with cephalothorax(Solved)
Name two classes of phylum arthropoda with cephalothorax
Date posted: December 26, 2018. Answers (1)
- Describe the route taken by water from the soil up to the evaporating surface of a plant
(Solved)
Describe the route taken by water from the soil up to the evaporating surface of a plant
Date posted: December 6, 2018. Answers (1)
- Describe the adaptations of the nervous system to its functions(Solved)
Describe the adaptations of the nervous system to its functions
Date posted: December 6, 2018. Answers (1)
- State the economic importance of members of Monera and Fungi and for each economic importance name a suitable or appropriate organism(Solved)
State the economic importance of members of Monera and Fungi and for each economic importance name a suitable or appropriate organism
Date posted: December 6, 2018. Answers (1)
- Describe the process of mitosis(Solved)
Describe the process of mitosis
Date posted: December 4, 2018. Answers (1)
- Describe how the various supportive tissues in plants adapt them to their habitats(Solved)
Describe how the various supportive tissues in plants adapt them to their habitats
Date posted: December 4, 2018. Answers (1)
- Discuss Lamarck’s and Darwin’s theories of evolution(Solved)
Discuss Lamarck’s and Darwin’s theories of evolution
Date posted: December 4, 2018. Answers (1)
- Describe the process of secondary thickening in a woody stem
(Solved)
Describe the process of secondary thickening in a woody stem
Date posted: December 4, 2018. Answers (1)
- What is secondary growth(Solved)
What is secondary growth?
Date posted: December 4, 2018. Answers (1)
- Which organelle is most abundant in white blood cell?(Solved)
Which organelle is most abundant in white blood cell?
Date posted: November 13, 2018. Answers (1)
- Explain how altitude affects the rate of breathing(Solved)
Explain how altitude affects the rate of breathing.
Date posted: November 8, 2018. Answers (1)
- Explain how mammals regulate their body temperature and relate this to their body size(Solved)
Explain how mammals regulate their body temperature and relate this to their body size
Date posted: November 7, 2018. Answers (1)
- Name 5 characteristics of phylum platyhelminthes?(Solved)
Name 5 characteristics of phylum platyhelminthes?
Date posted: November 7, 2018. Answers (1)
- Giving specific examples; explain the forms of aneuploidy in animals.(Solved)
Giving specific examples; explain the forms of Aneuploidy in animals.
Date posted: November 5, 2018. Answers (1)
- What is the difference between glycosuria and hyperglycemia?(Solved)
What is the difference between glycosuria and hyperglycemia?
Date posted: October 31, 2018. Answers (1)
- Describe the events that take place from the time when a mature pollen grain lands on stigma until formation of fruits and seeds(Solved)
Describe the events that take place from the time when a mature pollen grain lands on stigma until formation of fruits and seeds.
Date posted: October 30, 2018. Answers (1)