the story of us Flashcards
what is the genome
all the genetic material of an organism
how does RNA differ from DNA
- RNA is single stranded DNA is double
- RNA has a sugar called ribose DNA has a sugar called deoxyribose
- RNA has a U base DNA has a T base
describe the structure of DNA
- sugar phosphate backbone
- double helix
- bases C,T,A,G
- paired bases
- double stranded
describe the process of transcription
- two strands of DNA are unzipped by the enzyme helicase
- free nucleotides join to its complementary base to form mRNA
- mRNA made in the nucleus leaves via the nuclear pole
describe the process of translation
- mRNA strand travels to the ribosome and begins to pass through it
- every three mRNA bases are called codons and are read by the ribosome
- the complementary tRNA will attatch its three bases called anticodons to the mRNA
- tRNA transport amino acids to the ribosome
- amino acids begin to form peptides
- tRNA leaves leaving behind its amino acid chain which forms into a polypeptide
what is an allele
a version of a gene
what is a gene
a section of DNA that codes for a specific protien
what is homozygous dominant
BB
what is homozygous ressesive
bb
what is hetrozygous
Bb
explain why some mutations have a little effect on the phenotype of an organism
- could be recessive allele
- some triplets code for the same amino acid so no change in the protein
what is a mutation
a rare random change in the DNA
explain how mutation in a gene can affect the phenotype of an organism
- rare random change in the DNA
- change in bases in DNA
- change in the sequence of amino acids
- change in the enzyme/protien
describe the process of cloning a mammal
- egg cell is removed from the mammal
- nucleus is removed to form an enuclated cell
- body cell is removed from different sheep and nucleus is removed
- nucleus and enculeauted cell are fused together with an electric shock until mitosis starts occuring
- place embryo into the uterus of the surrogate mother
describe the process of micropropagation
- small section of plant called explant is cut from desired plant and sterilised
- placed in agar
- agar has nutrients and growth hormones
- grow and divide into small plants
- taken out and grown in soil
definition of a transgenic organism
transfer of genetic material from one species of organism to another
what can cause mutations
smoking, exposure to ionising radition
describe the process of vaccination
- weakened/dead pathogen is injected into the body
- they carry antigens
- lymphcytes produce antibodies
- memory cells are produced
- secondary immune response
- antibodies are produced quicker destroying the virus
embryonic stem cells
can turn into any cell
adult stem cells
can only turn into certain cells eg red blood cells
