Nine Weeks Test Week 4 Flashcards
How does a geneticist use pedigrees
To trace the inheritance of traits in humans
What is a pedigree
A chart that tracks which members of a family have a particular trait
Genetic disorders are caused by
DNA mutations or changes in chromosomes.
What would be the best way to predict the probability of a baby having cystic fibrosis
By studying the parents pedigree chart
A carrier is a person who has
One recessive and one dominant allele for a trait
What must occur for a girl to be colorblind
Each parent must have the recessive allele for colorblindness
Hemophilia is caused by
a recessive allele on the X chromosome
Down syndrome most often occurs when
Chromosomes fail to separate properly during meiosis
What genetic disorder results in abnormally shaped blood cells
Sickle cell disease
A DNA molecule is shaped like a
Spiral staircase
During DNA replication, adenine always pairs with
Thymine
Each ring of the DNA ladder is made of
A pair of nitrogen bases
A change in one or a few nucleotides that occur at a single point in a DNA sequence is known as a
Point mutation
A mutation that can change every amino acid following the point of mutation is known as
Frameshift
What r the different types of frame shift mutations
Insertion and deletion
What is the first thing U do when u look at a pedigree chart
Look for alike parents with different kids
What is the probability of producing a tall pea plant from a genetic cross between two hybrid tall pea plant
Three in four or 75%
If a homozygous black Guinea pig is crossed with a homozygous white Guinea pig, what is the probability that an offspring will have black fur.
Black is dominant
100%
A purebred chicken with white feathers is crossed with a purebred chicken with black feathers. Each of their offspring has both black and white feathers. Why does this happen
Both alleles for feather color are dominant
When sex cells combined to produce offspring, each six so will contribute
Half the number of chromosomes in body cells
Why are sex-linked traits more common in males than in females
A recessive allele on the X chromosome will always produce trait in a male
What must occur for a girl to be colorblind
Each parent must have a recessive allele for color blindness
Factors that control traits are called
Genes
Scientists call an organism that has two different alleles for a trait a…
Hybrid
What does the notation TT mean to geneticists
Two dominant alleles
What does the notation Tt mean to geneticists
One dominant allele and one recessive allele
What is probability
A number that describes how likely it is that an event will occur
What does a punnet square show
All possible outcomes of a genetic cross
And organisms physical appearance is it
Phenotype
The different forms of a gene are called
Alleles
An organisms genotype is it’s
Genetic makeup
An organism that has two identical alleles for a trait is
Homozygous
Chromosomes are made up of
Many genes joined together
As in the case of unlike magnetic poles, unlike electric charges
Attract each other
What causes charges to move in a circuit
Voltage
If an electric water heater uses 40kW of power and runs for eight hours what is the total amount of energy used
320 kilowatt-hours
An electric current will always flow
The path of less resistance
