Genetics MYP 5

Question 1

DNA full form

Answer 1

Deoxyribonucleic Acid

Question 2

Sugar of DNA

Answer 2

Deoxyribose

Question 3

Phosphate of DNA

Answer 3

Phosphate

Question 4

Nitrogenous Bases of DNA

Answer 4

A&T
G&C

A- Adenine
T- Thymine
G- Guanine
C- Cytosine

Question 5

Which nitrogenous base of DNA is stonger

Answer 5

G&C

Question 6

Why are genes important

Answer 6

Genes specify the sequences of amino acids, which are the building blocks of proteins.
This is important as Hormones and Enzymes both are proteins.

Question 7

Who discovered DNA originally?

Answer 7

Rosin Franklin

Question 8

How many alleles does each trait have?

Answer 8

Two (one from each parent)
The dominant one is expressed. A recessive gene will only be expressed if it is with another recessive gene.

Question 9

Homozygous

Answer 9

Both alleles are either dominant or recessive

Question 10

Hetrozygous

Answer 10

One allele is dominant and the other is recessive

Question 11

Protein Synthesis

Answer 11

Information comes out of nucleus and goes to ribosomes so proteins can be made

Question 12

Homologous chromosomes

Answer 12

Set of genes received from the father and set of genes received from the mother in the same place

Question 13

Genome/ Genotype

Answer 13

All of an organism’s genetic material

Question 14

Phenotype

Answer 14

What you look from the outside

Question 15

Haploid

Answer 15

Half the number of chromosomes in a place
In humans eggs and sperm are haploid

Question 16

Law of Segregation

Answer 16

During production of gametes, two copies of each hereditary factor segregate so that offspring acquire one factor from each parent

Question 17

Why must cells divide?

Answer 17

a) To form gametes
b) So we grow
c) To replace damaged cells

Question 18

When cells divide for growth and repair what is it called?

Answer 18

Mitosis (takes place in somatic cells)

Question 19

Somatic Cells

Answer 19

Any cell in the body except reproductive cells

Question 20

For reproductive purposes when cells divide what is it called?

Answer 20

Meiosis (takes place in reproductive cells and organs)

Question 21

Why is transcription and translation needed?

Answer 21

Because DNA is very large and cannot leave the nucleus of the cell, so in order to use a gene, it is necessary to make a copy of it which can be read by the ribosomes outside the nucleus.

Question 22

What is the copy of a particular gene from DNA known as?

Answer 22

mRNA

Messenger RNA

Question 23

Differences between mRNA and DNA

Answer 23

1) Much shorter than DNA as it only has one gene
2) Only a single strand long
3) Instead of the base Thymine, it has Uracil

Question 24

RNA Polymerase

Answer 24

Enzyme which binds to the DNA where the gene which needs to be copied starts.

Then, it moves along the gene and read the base one by one to make an mRNA strand

Question 25

mRNA bases will

Answer 25

always be complimentary to DNA

If there is an A, it will be Uracil
If there is a T, it will be A
If there is a G, it will be C
If there is a C, it will be G

Question 26

Codon/ Triplet and what does it do?

Answer 26

A group of 3 bases which codes for a specific amino acid
Can be DNA or mRNA

Question 27

Translation

Answer 27

The ribosome and mRNA strand bind together by adding one amino acid at a time

As the ribosomes move along the mRNA, the tRNA goes away and leaves the amino acids behind, and when the process it completed the ribosomes move away so the left behind amino acids can form a protein.

Question 28

How are amino acids brought to the ribosomes?

Answer 28

by tRNA

Transfer RNA

Question 29

tRNA

Answer 29

Carry the amino acids on the top and the anti-codon on the bottom.

The anti-codon is complimentary to the codon which codes for the amino acid on the top

They carry the correct amino acids in the correct order so the ribosomes chain them together

Question 30

Diploid

Answer 30

The presence of two complete sets of chromosomes in an organism’s cells, with each parent contributing a chromosome to each pair.

Question 31

Marfan syndrome

Answer 31

Direct Effect of Mutation: defective protein in connective tissue

Signs and Symptoms of the Disorder: heart and bone defects and unusually long, slender limbs and fingers

Mode of Inheritance: autosomal dominant

Question 32

Autosomal dominant

Answer 32

In this type of inheritance, only one parent needs to have an altered gene to pass it on to their child. The child has a 50% chance of inheriting the mutated gene, and a 50% chance of not inheriting it.

Question 33

Sickle cell anemia

Answer 33

Direct Effect of Mutation: Abnormal hemoglobin protein in red blood cells

Signs and Symptoms of the Disorder: Sickle-shaped red blood cells that clog tiny blood vessels, causing pain and damaging organs and joints

Mode in inheritance: Autosomal recessive

Question 34

Autosomal recessive

Answer 34

In this pattern, a child inherits one mutated gene copy from each parent, and both copies of the gene must be abnormal for the condition to develop

Question 35

Vitamin D-resistant rickets

Answer 35

Direct Effect of Mutation: Lack of a substance needed for bones to absorb minerals

Signs and symptoms of the disorder: Soft bones that easily become deformed, leading to bowed legs and other skeletal deformities

Mode of inheritance: X linked dominant

Question 36

Hemophilia A

Answer 36

Direct Effect of Mutation: Reduced activity of a protein needed for blood clotting

Signs and symptoms of the disorder: Internal and external bleeding that occurs easily and is difficult to control

Mode of inheritance: X-linked recessive

Question 37

Trisomy 21

Answer 37

Down Syndrome

Genotype: Extra copy (complete or partial) of chromosome 21 (see Figure below )

Phenotype effects: developmental delays, distinctive facial appearance, and other abnormalities

Question 38

Turner’s syndrome

Answer 38

Genotype: One X chromosome but no other sex chromosome (XO)

Phenotype effects: female with short height and infertility (inability to reproduce)

Question 39

Tripple- X syndrome

Answer 39

Genotype: Three X chromosomes (XXX)

Phenotype effects: Female with mild developmental delays and menstrual irregularities

Question 40

Klinefelter’s syndrome

Answer 40

Genotype: One Y chromosome and two or more X chromosomes (XXY, XXXY)

Phenotype effects: Male with problems in sexual development and reduced levels of the male hormone testosterone

Question 41

3 stages of cell interphase

Answer 41

First gap stage: G1–> 1st stage

S–> Synthesis (of DNA)

G2 phase

M–> Division (Mitosis / Meiosis)

Question 42

First gap stage

Answer 42

First stage of the preparatory phase of cell division.

The cell grows in size and the organelles grow in size.

Does not involve DNA replication.

Question 43

Synthesis phase

Answer 43

Second phase in interphase

The nucleus and the genetic information (DNA) will get duplicated

Centrosome also gets duplicated (organelles which helps in releasing threads used to separate sister chromatids).

Question 44

Second gap phase (G2)

Answer 44

Third step in interphase

Allows cell to grow more and makes more protein and organelles

Prepares the cell for mitosis

Question 45

PMAT

Answer 45

Prophase
Metaphase
Anaphase
Telophase

Question 46

Prophase

Answer 46

Nucleus is still there but starts disappearing

Chromosomes are visible and are condensing (they are thickening and visible)

The chromosomes are connected to the centromere and are referred to as sister chromatids

Question 47

Metaphase

Answer 47

Chromosomes line up in the middle of the cell

No nucleus membrane is present

Question 48

Anaphase

Answer 48

Chromosomes move away and move towards the poles of the cells

Spindles (fibres) that help the chromosomes move towards the end

Question 49

Telophase

Answer 49

Chromosomes are at the complete opposite ends (poles)

New nuclei are forming on each side to make new cells

Question 50

Cytokinesis

Answer 50

Final separation into two cells

The cytoplasm separates forming new cells.