NEW
Font size
WorksheetsGenes & Chromosomes
Total questions: 15
Worksheet time: 8mins
What does the notation TT mean to a geneticist?
two dominant alleles
heterozygous alleles
at least one dominant allele
one dominant and one recessive allele
What is the probability of producing a tall pea plant from a genetic cross between two hybrid tall pea plants?
one in four
two in four
three in four
four in four
What does a Punnett square show?
all of Mendel’s discoveries about genetic crosses
only the recessive alleles in a genetic cross
only the dominant alleles in a genetic cross
all the possible outcomes of a genetic cross
Which term refers to physical characteristics that are studied in genetics?
offspring
traits
generations
hybrids
An organism’s genotype is its
stem height
feather color
genetic makeup
physical appearance
Factors that control traits are called
parents
genes
purebreds
recessives
Scientists call an organism that has two different alleles for a trait a
dominant
purebred
factor
hybrid
What does the notation Tt mean to geneticists?
two dominant alleles
one dominant and one recessive allele
homozygous alleles
two recessive alleles
What is probability?
the number of times a coin lands heads up
the actual results from a series of events
the way the results of one event affect the next event
a number that describes how likely it is that an event will occur
If a homozygous black guinea pig (BB) is crossed with a homozygous white guinea pig (bb), what is the probability that an offspring will have black fur?
25%
50%
75%
100%
An organism’s physical appearance is its
dominance
genotype
phenotype
allele
When sex cells combine to produce offspring, each sex cell will contribute
twice the number of chromosomes in body cells.
the normal number of chromosomes in body cells.
half the number of chromosomes in body cells.
one fourth the number of chromosomes in body cells.
The different forms of a gene are called
factors
alleles
masks
traits
An organism that has two identical alleles for a trait is
homozygous
heterozygous
a phenotype
tall
A heterozygous organism has
three different alleles for a trait.
two identical alleles for a trait.
only one allele for a trait.
two different alleles for a trait.
