Genetics And Inhertitance Flashcards
Describe the structure of DNA
contains all info needed to make an organism
Holds instructions for growth and development for every living thing
Each gene comtaims instructions for a characteristic
It is made up of 2 strands
Strands joined togther by DNA bases
Twisted together and form double-helix shape
Where is DNA found in cell
DNA is found in the nuclues of cell
Define the the term gene:
Genes are small sections of a chromosome that hold the genetic code for particular characteristic
What is meant by an allele
An allele is a pair of genes that relate to a characteristic, that can be different or the same. You inhert one gene from one parent and one from the other.
A PAIR OF GENES ARE CALLED AN ALLELE
What is the defenition Variation within a species may be due to genetics or environment factors
The pressence of deifferences betweennliving things of the same species is variation
Describe the differences between dominant and recessive alleles
Dominant allele- only need 1 copy of the allele for the characteristic tobe expressed in the organism (BB)
Recessive allele- need 2 copies of the allele for the characteristic to be expressed in the organism (bb)
Distiguish between homozygous and hetrozygous alleles
Homozygous alleles are the same for the characteristic (BB or bb)
Hetrozygous alleles are both different for the characteristic (Bb)
What do genotype and phenotype mean?
Genotype- alleles that an organism has for a particular characteristic
Phenotype- the visible characteristic of an organism
What is a genetically inherited disorder and how inherited
Genetically inherited disorders are conditions passed from parents to their offspring in their genes
What is meant by selective breeding?
Selective breeding is choosingthe animal or plant that raise their characteristics
What are the stages of selective breeding?
1)Decide characteristic(s) of species is most important
2) Select parents that show high levels of the characteristic
3) breed individuals
4) select best offspring and breed again
5)repeat for generations
What are disadvantages of selective breeding
Disadvantages:
Reduces number of genes from species
Reduces variation within species
What is meant by genetic engeneering?
Scientists now alter an organisms genes to produce an organism with desired characteristics
What does GMO stand for?
Genetically Modified Organsim
Describe the process of genetically engineering an organsim
1) Take genes from another organism that show characteristic.
2) Put into plant or animal cells at very early stage of development
3) As organism develops, display the characteristics of foreign genes.
Advangtages and disadvatages of genetic engineering
Advantage- Guaranteed to make a change, many changes positive, creating more and healthier foods
Disadvantage- Some changes negative and unexpected. Many plants more tolerant to drought might also make plant become less tolerant to direct sunlight
Describe what is meant by a clone
A clone is an organism genetically identical to its parent. Means that it has same genes as its parent therefore look identical. Can happen naturally or artifically.
Process of cloning
1)Obtain mother cells, let mulitiply, stop when have enough
2) Take egg cell from another one, remove nucleus
3) Put both together and join electrically
4) Wait till embryo formed, place into animal and wait.
Advantages and disadvanges of cloning
Advantages- plants produce quickly and is cheap, plants are genetically identical so have desired characteristics
Disadvantages- Reduces genes available, increase chance of disease, change plant environment, destroy species
