B2- Nucleic acids, ATP and Inorganic ions

Question 1

What does ATP stand for?

Answer 1

Adonine triphosphate
It is considered as an immediate energy store

Question 2

What molecules does ATP consist of

Answer 2

Adenine, Ribose and Phosphates

Question 3

What does ADP stand for?

Answer 3

Adonine diphosphate

Question 4

Why is ATP not a good long-term energy store?

Answer 4

Because of the instability of the phosphate bonds

Question 5

Roles of ATP:

Answer 5

Metabolic processes: energy for building macromolecules
Movement: energy for muscle contraction
Active transport: energy to change shape of carrier protein in plasma membrane
Secretion: energy to form lysosomes
Activation of molecules: phosphorylation of compounds make them more reactive

Question 6

Inorganic ions

Answer 6

Hydrogen ion (H⁺) - determines pH, important for enzyme activity
Iron ion (Fe²⁺) - part of haem which is a prosthetic group for haemoglobin
Phosphate ion (PO₄³⁻) - in DNA and in ATP, and as activator of molecules
Sodium ions (Na⁺) - co-transport of Glc and AA across membranes

Question 7

What is semi conservative replication

Answer 7

It is when two copies of the original DNA molecule are produced

Question 8

What is the role of DNA helicase

Answer 8

The DNA helicase breaks the hydrogen bonds between the bases. This seperates the double helix in two strands.

Question 9

What is the role of DNA polymerase

Answer 9

They attach free nucleotides to the exposed DNA strands.
They work antiparallel so synthesis can occur in both directions.

Question 10

DNA

Answer 10

Holds the genetic information of all living organisms