Inheritance Flashcards
What are gametes?
Sex sells (E.g. egg cell)
What does homozygous mean?
Both alleles are dominant/recessive
What does heterozygous mean?
One allele is dominant and the other is recessive
What is genotype?
Genetic material (E.g. XX or XY)
What is phenotype?
Physical appearance (E.g. Female or male)
What is the genome?
An organisms entire genetic material
Describe the stages of genetic breeding
- Breed two parents with desired characteristic
- Select offspring with that characteristic and breed them
- Continue over many generations until all offspring have the characteristic
Name some uses of genetic engineering
- Disease/drought-resistant crops
- Crops that produce a higher yield
What is DNA made from?
Four different nucleotides repeating to form a polymer
What is a nucleotide made from?
A simple sugar, phosphate group, and a base attached to the sugar
What are the four bases in DNA called?
C A T G
What codes for an amino acids?
A sequence of three bases
What does the order of bases control?
The order of amino acids that make up a protein
What are the stages of meiosis?
- Chromosomes double in the parent cell
- They pair up opposite each other with spindle fibres attached
- Sections of DNA are swapped (crossing over)
- One of each pair of chromosomes are pulled to opposite poles of the cell
- The cell divides and a new nucleus membrane forms
- New spindle fibres form
- Chromosomes line up across the equator
- Chromosomes are pulled to poles again
- Both cells divide to create 4 haploid daughter cells that are genetically different from each other
What is an allele?
A version of a gene
What is evolution?
A change in the inherited characteristics of a population over time through the process of natural selection which may result in the formation of a new species
How can you tell when a new species is formed?
If two populations of one species can no longer interbreed to produce fertile offspring
What are the dangers of inbreeding?
The breed may be prone to diseases or inherited defects
What is genetic engineering?
Modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic
What are the stages of genetic engineering?
- Enzymes are used to isolate the required gene
- Gene inserted into a vector (plasmid or virus)
- Vector transports the gene to required cells
How is genetic engineering used to produce insulin?
- Human gene for producing insulin cut out with enzymes
- Plasmid taken from bacteria and cut using enzymes to give “sticky ends”
- Gene inserted into plasmid, then into bacteria
- Bacteria multiply rapidly by binary fission
- Insulin is produced
Why is genetic engineering done at an early stage of an organism’s development?
So they develop with desired characteristics
What are the four methods of cloning?
Tissue culture
Embryo transplants
Adult cell cloning
Taking cuttings
What is tissue culture?
In sterile conditions, tissue samples are grown on agar and many plantlets are potted in soil to grow
