Unit 2.3 DNA and Inheritance

Describe the structure of DNA

• DNA is found in the nucleus part of the cell

• DNA is made from two long chain of alternating sugar and phosphate structure, connected by bases. The two long chain of alternating sugar and phosphate structure forms a double helix shape.

Describe the pairing rules in DNA

A pairs with T

C pairs with G

Name the 4 bases in DNA

A = Adenine

T = Thymine

C = Cytosine

G = Guanine

How does the sequence of DNA affect the protein made in protein synthesis

DNA is a triplet code where 3 bases code for one amino acid and the order of amino acid determines the protein being produced

What is genetic profiling

A method of comparing DNA by cutting it into fragments and comparing the fragments with each other

Give 3 uses of genetic profiling

• Paternity testing

• Forensic identification

• Classification

Give 2 benefit of genetic profiling

• helps to catch criminals

• Used to identify the presence of disease causing genes

Ethical issues surrounding genetic profiling

Could be used against people by insurance companies based on a person’s predisposition to a certain disease

What is a gene

A section of DNA that codes for a protein

What are alleles

Different forms of genes

What is a chromosome

A linear DNA molecules that are tightly coiled around proteins. Chromosomes contains genes

What is a dominant alleles

The allele that show it self to and hide the recessive allele

What is a recessive allele

The allele that are hidden by the dominant alleles

What does homozygous mean

When an organism has two copies of the same allele

What does heterozygous mean

When an organism has two different version of the same gene (one dominant, one recessive)

What is genotype

The genes present for a trait

What is phenotype

The visible characteristics

What is selfing

When gametes from the same parent fuse

What is genetic engineering

A way of altering the genome of an organism

Two advantage and disadvantage of genetically modified crops

Advantages

• Better crop yield and less will die of diseases

• Food will last longer and taste better

Disadvantages

• The new genes can easily spread to other plants

• Unknown long term effect cause on health