3b (Inheritance)

Question 1

Genome

Answer 1

Entire DNA of an organism

Question 2

Gene

Answer 2

Section of a molecule of DNA that codes for a specific protein

Question 3

Nucleus of a cell contains…

Answer 3

Chromosomes on which genes are located

Question 4

Alleles

Answer 4

Any two or more alternative forms of a gene

Question 5

Genotype

Answer 5

The genetic makeup of an organism in terms of the alleles present e.g. Tt or GG

Question 6

Phenotype

Answer 6

The physical or other feature of an organism due to its genotype and it’s environment. e.g. a tall plant or green seed

Question 7

Homozygous

Answer 7

Having two identical alleles of a particular gene, e.g. TT or tt

Question 8

Heterozygous

Answer 8

Having two different alleles of a particular gene, e.g. Tt, Gg

Question 9

Dominant

Answer 9

An allele that is expressed (shows istlef) if it is present e.g. T or G

Question 10

Recessive

Answer 10

An allele that is expressed only if there is no dominant allele present e.g. t, g

Question 11

Allele

Answer 11

An allele is a version of a gene. One gene could have many alleles

Question 12

male pair of chromosomes

Answer 12

XY

Question 13

female pair of chromosomes

Answer 13

XX

Question 14

Mitosis is for…

Answer 14

growth, repair, cloning and asexual reproduction

Question 15

Mitosis (explanation)

Answer 15

• Chromosomes (genes) in dipliod cells clone / replicate
• They line up inside the cell
• They separate and the cell starts to divide
• Two identical daughter cells are made

Question 16

Meiosis is used to produce…

Answer 16

Sex cells (gametes)

Question 17

Meiosis (explanation)

Answer 17

• Chromosomes (genes) duplicate
• They pair up along the centre of the cell
• Maternal and paternal chromosomes pairs are swapped
• 2 divisions take place to make 4 haploid daughter cells

Question 18

Meiosis causes…

Answer 18

Genetic variation

Question 19

Enviromental variation such as:

Answer 19

climate, diets, accidents, culture, lifestyle

Question 20

Genetic variation

Answer 20

Genes variation is due to the environment as for example if a tall parent has a child and he has potential to grow high and he doesn’t eat, he isn’t going to grow

Question 21

Numer of chromosomes in diploid

Answer 21

46

Question 22

Numer of chromosomes in haploid

Answer 22

23

Question 23

Mutation

Answer 23

Rare and random change in DNA sequence coding for new alleles for gene

Question 24

Darwin’s theory

Answer 24

• Individuals in a Species show a range of variation caused by differences in genes
• Individuals with characteristics better adapted to the environment have a higher chance of survival, allowing thme to reproduce
• These genes are passed onto their offspring, showing evolution of species via natural selection

Question 25

Antibiotic resistance

Answer 25

• With the increase in antibiotic use, Bacteria will undergo rare and random mutations to show variation amongst bacterial population
• Bacteria that develops antibiotic-resistant gene will survive, increasing chances of survival
• This Bacteria will reproduce via binary fission to pass on this antibiotic-resistant gene to offspring that will inherit the same resistance
• Overtime, population of antibiotic-resistant Bacteria will increase, therefore making it more difficult to combat Bacterial growth