3b - Inheritance

Question 1

What is a gene ?

Answer 1

A section of DNA which codes for one protein

Question 2

What are the four bases

Answer 2

Adenine
cytosine
guanine
thymine 

Question 3

How many chromosomes do humans have in each nucleus?

Answer 3

46

Question 4

Order cell Chromosome gene and nucleus from smallest to largest

Answer 4

Gene, Chromosome, nucleus, cell

Question 5

How does DNA replicate?

Answer 5

• the double helix strand is split in half
• free nucleotides bond with the opposite bases
• a new DNA complimentary strand is created

Question 6

What kind of process is DNA replication?

Answer 6

Semiconservative process

Question 7

What is a protein?

Answer 7

Polymer of amino acids linked by peptide bonds

Question 8

Where is protein created?

Answer 8

Ribosomes

Question 9

What are proteins needed for?

Answer 9

• Enzymes

- cell and tissue growth + repair

Question 10

In RNA what is the sugar?

Answer 10

Ribose

Question 11

In DNA what is the sugar?

Answer 11

Deoxyribose

Question 12

Describe RNA

Answer 12

- single stranded

• small
• adenine pairs with URACIL
• sugar is ribose

Question 13

Describe transcription

Answer 13

RNA binds to DNA strand and travels along, building an mRNA molecule from the template strand

Question 14

What happens once transcription is complete

Answer 14

mRNA passes into the cytoplasm where it undergoes translation

Question 15

Describe translation

Answer 15

• mRNA is read to produce a protein chain

- transfer RNA (tRNA) carries specific individual amino acids into the ribosome

Question 16

What does each tRNA molecule have

Answer 16

Three bases which match up to corresponding bases on the mRNA

Question 17

What are mutations

Answer 17

Rare random events that change the DNA sequence

Question 18

How can mutations have a positive effect

Answer 18

By increasing the chance of successful reproduction and survival

Question 19

How can mutations have a negative effect

Answer 19

By decreasing the chance of successful reproduction and survival

Question 20

How can mutations be caused

Answer 20

• mistakes in copying DNA

- the effects of radiation

Question 21

What is the XX chromosome?

Answer 21

Female

Question 22

What is the XY chromosome?

Answer 22

Male

Question 23

What is an allele?

Answer 23

Different versions of a gene

Question 24

What is the definition of heterozygous?

Answer 24

When the 2 alleles of a gene are different

Question 25

What is the definition of homozygous?

Answer 25

When the 2 alleles of a gene are the same

Question 26

What is the definition of phenotype ?

Answer 26

The observable characteristics of an organism

Question 27

What is the definition of genotype?

Answer 27

The combination of alleles which control each characteristic

Question 28

Who is responsible for determining the sex of offspring and why?

Answer 28

The father because only he can pass on a Y chromosome

Question 29

What is mitosis ?

Answer 29

Cell devision which forms two identical cells

Question 30

What is meiosis?

Answer 30

Cell devision which forms 4 non identical haploid cells

Question 31

What are the uses of mitosis?

Answer 31

- Asexual reproduction - growth - repair

Question 32

Where does meiosis happen in Humans?

Answer 32

Reproductive organs only

Question 33

What is the definition of codominance?

Answer 33

When both alleles within a genotype are expressed in the phenotype of an individual

Question 34

What are family pedigrees used for?

Answer 34

To trace the pattern of inheritance of a characteristic through generations of a family

Question 35

What is monohybrid inheritance?

Answer 35

The inheritance of characteristics controlled by a single gene

Question 36

What is monohybrid inheritance determined by?

Answer 36

A punnet square

Question 37

Why is meiosis important?

Answer 37

- increases genetic variation of offspring

Question 38

What are the different kinds of variation within a species?

Answer 38

Genetic, environmental or both