B6 - Inheritance, Variation and Evolution

Define sexual reproduction

Reproduction requiring two gametes created by meiosis, producing genetically non-identical offspring

Define asexual reproduction

Reproduction involving a single parent producing genetically identical offspring using mitosis

Define haploid

one set of chromosomes

Define diploid

two complete sets of chromosomes, one from each parent

What is mitosis used for?

Growth and repair of tissues and production of new cells as replacements

Define meiosis

A type of cell division that produces gametes with 23 chromosomes each

What can be said about meiosis genetically?

Produces genetically non-identical offspring

Are gametes haploid or diploid?

Haploid

Are somatic cells haploid or diploid?

Diploid

What two things cause genetic variation in meiosis?

Crossing over of DNA between chromosomes and independent variation of chromosomes

Define genome

The entire genetic material of an organism

Define genetic mutation

A change in base

What are the four types of genetic mutation?

Substitution,

Insertion,

Deletion,

Inversion

What is dangerous about insertion and deletion mutations that aren't done in multiples of three?

They cause a frame shift

What are the major causes of mutation?

Irradiation,

Cell division,

Carcinogens,

Age (cell division going wrong)

Define genotype

The alleles the organism has

Define phenotype

The physical appearance of an organism (expression of the alleles)

Define homozygous

Two identical alleles

Define heterozygous

Two different alleles

Define allele

Different forms of a gene

Define inherited disorder

Some part of a phenotype that malfunctions, passed down through the alleles of the parents

Is cystic fibrosis recessive or dominant?

recessive

Is polydactyly recessive or dominant?

dominant

Explain why a large amount of human insulin can be obtained by genetically engineering one bacterium.

Bacterium reproduce very quickly at optimum conditions

Describe how a bacterial cell can be genetically engineered to make human insulin

1. Insulin gene cut out of a human chromosome

2. Plasmid removed from bacterial cell by an enzyme

3. Insulin gene inserted into plasmid

4. New plasmid/insulin inserted into the bacterial cell

What organ of a pig used to be used to produce insulin?

Pancreas

Why are scientific names more useful than common names?

They are the same in every language

What is the outer casing of a DNA double helix known as?

a sugar-phosphate backbone

What codes for an amino acid?

one triplet of bases

what is a mutation?

change in DNA sequence

What are the three types of mutation?

substitution, insertion, deletion

Why is protein synthesis needed?

the specific sequence of bases have to be read by a ribosome which are outside of the nucleus and the DNA is too big to leave the nucleus

What is the name of the enzyme that binds to the template strand to create mRNA?

RNA polymerase

How do amino acids bond?

tRNA molecules bring amino acids and its anticodon binds to the complementary mRNA which detaches

Define gamete

sex cell

How many chromosomes are in each gamete?

23 chromosomes

What does asexual reproduction produce?

genetically identical offspring

How does asexual reproduction occur?

mitosis

What is plant sperm?

pollen

What type of cell is a gamete?

haploid

Name a disadvantage of sexual reproduction

time consuming, impossible for isolated populations

Are gametes haploid cells?

Yes

How many chromosomes does a human gamete have?

23

As a result of meiosis, how many cells are produced?

4 genetically non identical

Is cystic fibrosis dominant or recessive?

recessive

Is polydactyly dominant or recessive?

dominant