Nucleic Acids

Question 1

Nucleic Acids

Answer 1

• like proteins, they are also polymers
• made of repeating NUCLEOTIDE subunits
• CONTAIN THE INSTRUCTIONS FOR PROTEIN SYNTHESIS
• DNA and RNA

Question 2

Polymer

Answer 2

a mol made up of repeating subunits (monomers)
eg: Proteins are made of amino acids

Question 3

Monomer

Answer 3

repeating subunit in polymer made of simple chemical units
eg: Amino Acids (monomer)- made of- C, H, Amino group (-NH2), Carboxyl group (-COOH), R group (variable side chain)

Question 4

Monomer of DNA

Answer 4

Monomer: Nucleotide

Question 5

Monomer of: Polysaccharides

Answer 5

Monomer: Monosaccharide

Question 6

Monomer of: Lipids

Answer 6

Monomer: Glycerol + Fatty acids
Polymer: Triclyceride

Question 7

Monomer of: Protein

Answer 7

Monomer: Amino Acid
Polymer: Polypeptide Chain/ protein

Question 8

Types of RNA

Answer 8

• Messenger RNA (mRNA)
• Transfer RNA (tRNA)
• Ribosomal RNA (rRNA)

Question 9

the replication of a double stranded DNA molecule begins when the strands separate at the
hint: what bond keeps base pairs bonded

Answer 9

hydrogen bonds

Question 10

which pair of molecules, when bonded together, would most likely be found in a nucleotide of DNA?

Answer 10

Deoxyribose sugars+ Nitrogenous base (bonded at 1’ carbon)

Question 11

Polymer

Answer 11

a mol made up of repeating subunits (monomers)

Question 12

Monomer

Answer 12

repeating subunits of polymer made of simpler chemical units

Question 13

Monomer and Polymer of DNA/ RNA?

Answer 13

Nucleotide, Nucleic Acids

Question 14

Monomer of proteins?

Answer 14

Amino acids
makes- polypeptide chain/protein

Question 15

Monomer of polysaccharides?

Answer 15

Monosaccharide

Question 16

Monomer of lipids (fats)?

Answer 16

Monomer: Glycerol + Fatty acids
Polymer: Triglyceride (e.g., fats, oils)

Question 17

Types of RNA

Answer 17

mRNA (messenger RNA)

tRNA (transfer RNA)

rRNA (ribosomal RNA)

Question 18

Subunits of RNA

Answer 18

made up of nucleotides
- Phosphate group
- Ribose sugar
- Nitrogenous base: A, U, G, C

Question 19

Subunits of DNA

Answer 19

made up of nucleotides
- Phosphate group
- Deoxyribose sugar
- Nitrogenous base: A, T, G, C

Question 20

Roles of DNA and RNA

Answer 20

DNA → contains the instructions coding for synthesis of proteins
RNA → different types of RNA are involved in bringing the different components required for protein synthesis to the organelle that performs this process

Question 21

RNA ROLES

Answer 21

Ingredients- Amino acids- tRNA
Recipe- Instructions- mRNA
Chef- Organelle-ribosome- rRNA

Question 22

DNA replication is a __

Conservative Process
Semi-Conservative Process
not Conservative Process

Answer 22

Semi-Conservative Process

Each new DNA molecule has one original, old (parent) strand and one newly synthesised (daughter) strand.
parent strand= template strand
daughter strand= coding strand

Question 23

DNA backbone

Answer 23

The alternating chain of sugar and phosphate to which the nitrogen bases are attached

Question 24

Hydrogen Bonds

Answer 24

These connections are weak between the nitrogen bases that form the “rungs” of the DNA ladder.

Question 25

These connections are weak between the nitrogen bases that form the "rungs" of the DNA ladder.

Answer 25

Hydrogen Bonds

Question 26

helicase

Answer 26

An enzyme that unzips the DNA double helix during DNA replication

Question 27

DNA polymerase

Answer 27

- Adds nucleotides to the growing DNA strand in the 5' → 3' direction. - Proofread for errors to ensure accuracy. - DNA Polymerase I: Replaces RNA primers with DNA. - DNA Polymerase III: Main enzyme for strand elongation.

Question 28

primer in DNA replication?

Answer 28

- A short RNA sequence made by primase. - Provides a starting point for DNA polymerase to add nucleotides. - Later replaced by DNA Polymerase I with DNA nucleotides.

Question 29

What is the leading strand in DNA replication?

Answer 29

- Synthesized continuously in the 5' → 3' direction. -Moves toward the replication fork. -Requires only one primer. Built by DNA Polymerase III.

Question 30

replication fork

Answer 30

- Y-shaped structure where DNA unzips. - Formed by helicase breaking hydrogen bonds.

Question 31

Leading strand

Answer 31

Continuous synthesis 3' to 5' end (toward the replication fork) when a new strand is created, it goes 5' to 3'. always synthesized in the 5' → 3' direction, but the direction of the template strand (3' → 5' or 5' → 3') determines how replication occurs (continuously or in fragments).

Question 32

Lagging strand

Answer 32

Discontinuous (Okazaki fragments) 5' to 3' end (moving away from the replication fork) when a new strand is created, it goes 3' to 5'. always synthesized in the 5' → 3' direction, but the direction of the template strand (3' → 5' or 5' → 3') determines how replication occurs (continuously or in fragments).

Question 33

5' end of deoxyribose sugar

Answer 33

The part of the new DNA strand that DNA polymerase is UNABLE to build from. Can be identified by the phosphate end of the backbone.

Question 34

3' end of deoxyribose sugar

Answer 34

the end to which free floating nucleotides can be added, the sugar end of the nucleotide.

Question 35

Ligase

Answer 35

An enzyme that connects portion of DNA during replication "glue" that joins the Okazaki fragments on the lagging strand by forming phosphodiester bonds, making the strand continuous.

Question 36

Why does DNA replication occur?

Answer 36

DNA replication occurs before a cell divides so each new cell can have a complete copy of the DNA enabling growth, repair, and reproduction.

Question 37

DNA replication

Question 38

Purines

Answer 38

nitrogenous bases that include adenine (A) and guanine (G). They are double-ringed structures in DNA and RNA.

Question 39

Pyrimidines

Answer 39

nitrogenous bases that include cytosine (C), thymine (T), and uracil (U). They have a single-ring structure in DNA and RNA.

Question 40

Semi-conservative replication

Answer 40

In semi-conservative replication, each half of the original DNA strand serves as a template for a new strand. The result is two new DNA molecules, each with one old strand and one new strand.

Question 41

DNA replication steps

Answer 41

1. Unwinding: Helicase breaks hydrogen bonds between bases- unzips the double helix 2. Priming: Primase adds a short RNA primer to the template strand to start replication. 3. Elongation: leading strand, DNA polymerase adds nucleotides continuously in the 5' → 3' direction. lagging strand, DNA polymerase adds nucleotides in short fragments (Okazaki fragments) in the 5' → 3' direction. 4. Joining: DNA ligase seals the gaps between Okazaki fragments on the lagging strand to make a continuous strand. 5. Proofreading: DNA polymerase checks for errors and corrects them.