Genetics Flashcards
The haploid gamete of plant x has 12 chromosomes. 2 of these gametes fuse to create a zygote. How many chromosomes are in the zygote
24 chromosomes
How does meiosis introduce genetic variation
When the cell divides some of the chromosomes from the organism’s father and some from the mother go into each new cell. The mixing up of the genes creates genetic variation
Strawberry plants can reproduce asexually. Give an example of an advantage and disadvantage of this process
Reproducing asexually can produce a lot of offspring very quickly.
It Produces genetically identical organsims. If environmental conditions changed e.g. temperature increase, the whole population could be wiped out.
Which DNA bases pair up according to complementary base pairing
Adenine and Thymine
Ctyosine and Guanine
What are nucleotides made of
A sugar
A phosphate
One base
Nucleotide is part of a DNA strand
Why is it useful to use salt when extracting DNA from fruit cells
The salt helps the DNA to stick together
Explain how a gene can code for a particular protein
The order of bases in a gene determines the order of amino acids in a protein. This could change protein
Explain how a genetic variant can result in a protein with a very low level of activity
A gentetic variant could alter the sequence of amino acids coded for by a gene, which could affect the shape of a protein decreasing its activity
What is transcription?
RNA polymerase binds to a region of non-coding DNA in front of a gene
The 2 DNA strands unzip and the RNA polymerase moves along one strand of the DNA
It uses the coding DNA in the gene as a template to create mRNA. Base pairing between the DNA and mRNA ensures rhe mRNA is complementary to the gene
Once made, the mRNA molecule moves out of the nucleus and joins with a ribosome
Suggest why Mendel’s work wasn’t realised as signifcant straight away?
Scientists of the time didn’t properly understand Mendel’s findings because they didn’t know about genes, DNA and chromosomes
How can information from the human genome project be used to help prevent individuals from developing certain diseases.
Doctors could give check ups regularly to ensure early treatment to a disease a person is susceptible to due to their genes.
If doctors knew a person’s genome, they could tell the person the best diet and lifestyle to avoid likely problems
