M6 Subtopic 2

Question 1

DNA stands for

Answer 1

Deoxyribonucleic Acid

Question 2

molecule that carries the genetic instructions for life

Answer 2

DNA

Question 3

It is made up of nucleotides (4)

Answer 3

Adenine, Thymine, Cytosine, Guanine

Question 4

Who first discovered the Double Helix structure?

Answer 4

James Watson and Francis Crick in 1953,

Question 5

DNA is composed of two long strands that coil around each other to form a ________

Answer 5

Double Helix

Question 6

Each strand of DNA is made up of repeating units called…?

Answer 6

Nucleotides

Question 7

Each nucleotide consists of three components:

Answer 7

A phosphate group
A sugar molecule (deoxyribose)
A nitrogenous base

Question 8

The two strands of the DNA double helix are _____________, meaning the sequence of bases on one strand determines the sequence on the other

Answer 8

Complementary

Question 9

Pairing of the nucleotides?

Answer 9

Adenine - Thymine / Uracil (RNA)
Cytosine - Guanine

Question 10

describes the flow of genetic information from DNA to RNA to protein.

Answer 10

central dogma of molecular biology

Question 11

process by which a cell copies its entire genome before cell division, ensuring that each daughter cell receives an identical set of genetic instructions

Answer 11

DNA replication

Question 12

Steps of DNA replication, transcription, and translation.

Answer 12

Initiation
Elongation
Termination

Question 13

begins at specific sites on the DNA molecule called origins of replication. Enzymes like helicase unwind the DNA double helix, creating replication forks

Answer 13

Initiation (replication)

Question 14

DNA polymerase, the enzyme responsible for synthesizing new DNA strands, adds nucleotides to the exposed DNA template strands in a complementary fashion (A-T, C-G). On the leading strand, DNA is synthesized continuously, while on the lagging strand, it is synthesized in short fragments.

Answer 14

Elongation (replication)

Question 15

In elongation, on the lagging strand, it is synthesized in short fragments called?

Answer 15

Okazaki fragments

Question 16

It continues until the entire molecule has been copied. Enzymes like ligase seal the gaps between the Okazaki fragments, creating a continuous strand. The result is two identical DNA molecules, each with one old strand and one newly synthesized strand (semi-conservative replication).

Answer 16

Termination (replication)

Question 17

the process by which the information encoded in a gene’s DNA sequence is transcribed into messenger RNA (mRNA).

Answer 17

Transcription

Question 18

Where does transcription take place for eukaryotic and prokaryotic cells?

Answer 18

Nucleus (Eukaryotic)
Cytoplasm (Prokaryotic)

Question 19

RNA polymerase binds to a specific region of the DNA called the promoter, signaling the start of transcription.

Answer 19

Initiation (transcription)

Question 20

RNA polymerase unzips the DNA and adds complementary RNA nucleotides to form an mRNA strand

Answer 20

Elongation (transcription)

Question 21

Transcription ends when RNA polymerase reaches a terminator sequence, releasing the newly formed mRNA.

Answer 21

Termination (transcription)

Question 22

The process by which the genetic code carried by mRNA is decoded by ribosomes to synthesize a specific protein.

Answer 22

Translation

Question 23

Where does translation occur in both eukaryotic and prokaryotic cells?

Answer 23

Cytoplasm

Question 24

The ribosome assembles around the mRNA, and the first tRNA (transfer RNA) binds to the start codon (AUG) on the mRNA

Answer 24

Initiation (Translation)

Question 25

The ribosome moves along the mRNA, reading each codon and bringing in the corresponding tRNA with its attached amino acid. The amino acids are linked together to form a polypeptide chain

Answer 25

Elongation (Translation)

Question 26

When the ribosome reaches a stop codon (UAA, UAG, or UGA), the translation process ends, and the newly synthesized protein is released.

Answer 26

Termination (Translation)

Question 27

the process by which the instructions in a gene are used to synthesize a functional product, typically a protein.

Answer 27

Gene expression

Question 28

Eye color is determined by the amount and type of pigment present in the iris.

What is this pigment called?

Answer 28

Melanin

Question 29

Types of Mutations

Answer 29

Silent
Missense
Nonsense
Frameshift

Question 30

These mutations change a nucleotide without altering the amino acid sequence of the protein, usually having no effect on the protein’s function

Answer 30

Silent Mutation

Question 31

These mutations result in a different amino acid being incorporated into the protein, which may affect the protein’s function, depending on the importance of the altered amino acid.

Answer 31

Missense Mutation

Question 32

These mutations introduce a premature stop codon, leading to the production of a truncated, usually nonfunctional protein.

Answer 32

Nonsense Mutation

Question 33

Insertions or deletions that shift the reading frame can result in a completely different and often nonfunctional protein.

Answer 33

Frameshift Mutation