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
