B16: Inheritance

Question 1

Inheritance

Answer 1

Inheritance is the transmission of genetic information from generation to generation

Question 2

Chromosome

Answer 2

Chromosomes are made of DNA which contains genetic information in the form of genes

Question 3

Allele

Answer 3

An alternative form (version) of a gene

Question 3

Gene

Answer 3

A length of DNA that codes for a protein

Question 4

Characteristics of Chromosomes

Answer 4

1) Arranged in pairs
2) 46 chromosomes in every nucleus of a human body
3) 23 from father and 23 from mother

Question 5

Example of Genes

Answer 5

Brown eyed protein, curly hair protein, brown skin protein

Question 6

Example of Allele

Answer 6

Blue eyed allele or Brown eyed allele

Question 7

Haploid nucleus

Answer 7

A nucleus containing a single set of chromosomes. Eg: gametes: sperm and egg)/ n=23

Question 8

Diploid nucleus

Answer 8

A nucleus containing two sets of chromosomes; arranged in pairs. Eg: In all body cells/ 2n=46

Question 9

Sex chromosomes

Answer 9

The 23rd pair of chromosomes; determine the gender of the individual

Question 10

Males sex chromosomes

Answer 10

XY

Question 11

Females sex chromosomes

Answer 11

XX

Question 12

Mitosis

Answer 12

Mitosis is a nuclear division of the nucleus giving rise to genetically identical cells.

Question 13

Roles of Mitosis

Answer 13

-Growth
-Repair of damaged tissues
-Replacement of cells
-Asexual reproduction

Question 14

Meiosis

Answer 14

Reduction division in which the chromosome number is halved from diploid to haploid resulting in genetically different cells

Question 15

Roles of Meiosis

Answer 15

-Reduction: Diploid to haploid
-Genetic Variation
-To make gametes

Question 16

Genotype

Answer 16

The genetic make up of an organism and in term of the alleles present in symbols

Question 17

Phenotype

Answer 17

The observable feature of an organism. Eg : brown eyes

Question 18

Homozygous

Answer 18

Having two identical alleles of a particular gene. Homo means same

Question 19

Pure bred

Answer 19

Identical homozygous individuals that breed together

Question 20

Heterozygous

Answer 20

Having two different alleles of a particular gene. Hetero means different

Question 21

Not pure bred

Answer 21

Heterozygous individuals will not be pure bred

Question 22

Dominant allele

Answer 22

An allele that is expressed if it is present in the genotype. The allele which is seen in the individual

Question 23

Recessive allele

Answer 23

An allele that is only expressed when there is no dominant allele of the gene present in the genotype. The allele that cannot be seen in the individual but might be seen in their future generation.

Question 24

Pedigree charts

Answer 24

A chart that shows the pattern of inheritance in a family tree.

Question 25

Punnett square

Answer 25

A diagram that predicts the genotypes of offspring from a breeding experiment or cross.