DNA - The code of life and RNA

Question 1

Functions of the nucleus (2)

Answer 1

• Chromosomes store genetic material

- Regulates the structure and metabolism of the cell

Question 2

Nucleic acids

Answer 2

Organic molecules that control the synthesis of proteins in all living cells by storing and transferring genetic information

Question 3

Chromosomes

Answer 3

Long, thin, thread-like structures composed of DNA that is wrapped around proteins called histones

Question 4

Gene

Answer 4

A short segment of a DNA molecule that codes for a particular protein

Question 5

Discovery of DNA

Answer 5

Rosalind Franklin, stollen by James Watson and Francis Crick

Question 6

Nucleotides

Answer 6

• Sugar molecule
• Phosphate group
• Nitrogenous base
  > Adenine
  > Guanine
  > Cytosine
  > Thymine

Question 7

Non-coding DNA (4)

Answer 7

• 2% of DNA
• caries no information to produce proteins
• regulates and controls expression of genes, when on and when off
• protects against mutations

Question 8

Interphase

Answer 8

The period between two consecutive cell divisions when the call performs normal metabolic activities

Question 9

DNA replication

Answer 9

Double helix unwinds. Hydrogen bonds break. DNA unzips. Free floating nucleotides build complementary DNA strands. Original DNA rejoins and winds up.

Question 10

Types of RNA

Answer 10

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

Question 11

Protein synthesis

Answer 11

The process whereby proteins are manufactured in living cells

Question 12

Order of protein synthesis (2)

Answer 12

Transcription of DNA

Translation of RNA to proteins

Question 13

Gene

Answer 13

A group of triplet bases that code for the synthesis of a specific protein

Question 14

Transcription

Answer 14

The process where mRNA obtains the code for protein synthesis from DNA

Question 15

Process of transcription (4)

Answer 15

• two strands of DNA unzip, under guidance of RNA polymerase enzyme
• free floating RNA nucleotides in the neoplasm build complimentary mRNA strand
• mRNA move away out of pores in the nuclear membrane and DNA rejoins
• mRNA is taken to ribosomes in the cytoplasm

Question 16

Process of translation (5)

Answer 16

• mRNA strand attaches to ribosome
• tRNA in the cytoplasm pics up amino acids and brings them to ribosome
• anticodons of tRNA link to codons of mRNA, so amino acids join in right order
• amino acids form peptide bonds with each other
• tRNA go to pick up another amino acid

Question 17

Mutation

Answer 17

Any change in the genetic composition of an organism

Question 18

Mutagens

Answer 18

Physical or chemical agents that cause mutations

Question 19

Examples of mutagens (5)

Answer 19

> x-rays
> UV light
> Toxic chemicals
> Viral infections
> Extreme heat

Question 20

Types of mutations (2)

Answer 20

• Gene mutations

- Chromosome mutation

Question 21

Gene mutation (3)

Answer 21

• Change in the nucleotide sequence in the DNA of a molecule
• Messes up protein synthesis
• Can occur during replication, transcription or during meiosis

Question 22

Types of gene mutations (4)

Answer 22

• Substitution: When one nitrogenous base is replaced with another (CGG -> CAG)
• Deletion: Where one or more nitrogenous base are lost, resulting in a frame shift
• Insertion: Where one or more nitrogenous bases are added, resulting in a frame shift
• Inversion

Question 23

DNA Profiling

Answer 23

Use non-coding DNA that differs from person to person to identify something

Question 24

Uses of DNA profiling (5)

Answer 24

• Identify crime suspects
• Proof of paternity
• Determine probability or cause of genetic defects
• Tracing missing persons
• Establish compatibility for organ transplants