dna and inheritance Flashcards
(23 cards)
what does DNA contain and what does it determine
coded information and characteristics
What form the backbone of DNA strands?
Alternating sugar and phosphate molecules
what shape does a DNA molecule with two strands coiled together make?
double helix
what are the complimentary base pairs?
adenine and thymine
cytosine and guanine
What are the complementary base pairs joined together by?
weak hydrogen bonds
What is a gene?
A small section of DNA found on a chromosome
What decides the order of the amino acids in a protein?
a sequence of 3 bases in the gene which is called a triplet
what are the properties and functions of each protein determined by?
The particular amino acids and the order their present in
what are the exceptions to unique DNA?
identical twins and clones
what is the process of genetic profiling
cutting the DNA extracted from blood/semen into short pieces which are then separated into bands
How can genetic profiles be compared?
to see how similar the pattern of bonding in different DNA samples are
3 uses of comparing genetic profiles
paternity testing to see if a man is the father of a particular child
Species classification
Forensic science were DNA is taken from a crime scene and is compared to a DNA sample from a suspect
why would doctors use genetic profiles
to diagnose the presence of certain genes which may be associated with a particular disease
ethical issues of dna profiling
some people think that store genetic profiles is an invasion of privacy and worry if insurance companies gained acesss they may refuse to insure people based on it
which chromosome pairs control the characteristics and which control the sex?
22 pair
23rd pair
What’s chromosomes do males and females have?
XY
XX
what happens to the chromosomes when making sperm
the X and Y chromosomes are drawn apart in the first division so it’s a 50/50 percent change each sperm gets a X or Y chromosome
what is single gene inheritance
when characteristic are controlled by 1 gene
what are alleles
different types of the same gene eg green or blue eyes
how many alleles do we have in each gene and where
2 versions and 1 on each characteristic
homozygous and heterozygous meaning
if an organism has two same alleles for a particular gene, it’s homozygous for that trait
if two alleles are different for that particular gene it’s heterozygous
if 2 alleles are different then which characteristic is show
the dominant one if it’s in a heterozygous as it overrules the recessive
for the recessive to be shown it has to be in homozygous pair where both alleles are recessive
what is a genotype and phenotype
the combination of alleles you have eg Bb
You’re alleles work at a
molecular level to determine which physical characteristics you have
