DNA and Inheritance

Created by

Ela Jones

Cards (49)

What is DNA
Is a double stranded polymer of nucleotides that form a double helix
What does DNA do?
Protein so it codes and makes protein
What does each strand of DNA consist of?
Alternating sugars and phosphate molecules
What are the 4 bases
A - adenine
T - Thymine
C - Cytosine
G - Guanine
What base pairs with what base
C pairs with G
T pairs with A
What is a gene
A section of DNA that codes for a protein
Triplets
A sequence of three bases in a gene forms a triplet. Each triplet codes for an amino acid. Order of amino acids determine the structure and function of the protein formed
What is genetic profiling?
Is a method of comparing DNA
Method of Genetic Profiling
Sample of cells collected
DNA extracted from cells
DNA sample cut into fragments using enzymes
Fragments separated into bands, creating a genetic profile
What can genetic profiling be used for?
Paternity Testing
Forensics
Classification
Detecting Genes
What a gene?
A length of DNA that codes for the production of a particular protein
What a Allele?
A version of a gene
What is a Gamete?
Reproductive cells that contain a single copy of each chromosome
What is a dominant?
Describes an allele that is always expressed. Represented with a capital letter
What is a Recessive?
An allele that is only expressed in the absence of a dominant allele. Represented with a small letter
What is a Homozygous?
Having two identical alleles of a gene e.g FF
What is a Heterozygous?
Having two different alleles of a gene e.g Ff
What is a Genotype?
An organisms genetic composition describes all alleles
What is a Phenotype?
An organism observable characteristic
What is a F1 generation?
First generation in a genetic cross - the offspring produced when two organism interbreed
What is F2 generation?
Second generation in a genetic cross - the offspring produced when two organism from the F1 generation are bred together
What is a selfing?
An artificial method of self pollinating plants
Who first discovered Genetics?
Gregor Mendel (1800s)
Diagram
Diagram:
Dominant and Recessive Alleles
In the body cells, chromosomes occurs in pairs. This means that the genes on them also occur in pairs.
Example of Dominant and Recessive Alleles
For example a pair of chromosomes may each contain a gene that code for eye colour. The different forms of genes are called alleles. In a pair of alleles, one may code for blue eyes and one may code for brown eyes. Alleles are simply different forms of the same type of gene.
Dominant Alleles
In most cases one allele is dominant over the other and always hides it. The allele is hidden is called the recessive allele. Because of this recessive alleles are rarer than dominate ones.
Dominate alleles in leopard
In coat colours of leopards the spotted form is dominant to the black form. So the black form is recessive. For this reason the normal spotted form of leopard is much more common than the black for or panther
Single gene inheritance
Most characteristics of an organism are determined by multiple genes interaction, however some are determined by a single gene
What is Monohybrid Inheritance?
What is the inheritance of a single gene
What do you use a pundit square?
Can be used to illustrate the single gene inheritance
Examples of Pundit Squares
Examples
Examples of Pundit Square
Questions
Sex determine in humans
Sex chromosomes are one of the 23 pairs of chromosomes that determine sex
What are male chromosomes
X and Y
What are female chromosomes
X and X
Sex determine
Diagram
What is genetic modification?
The process of taking a gene from one organism and inserting it into another
What characteristics might scientists introduce to crops when they genetically modify them?
Resistance to pest
Resistance to herbicide
Resistance to draught
Contain more nutrients
Ripen early
State the most common use of genetic modification
Farm animals, crops and bacteria