bio 1201 gregg exam 3 Questions
and Answers 2024/2025
the units of heredity and are made up of segments of DNA
genes
how many chromosomes do humans have in the nucleus of their somatic cells?
46 chromosomes (23 pairs)
the two chromosomes in each pair are called...
homologous chromosomes/homologs
each pair of homologous chromosomes includes...
one chromosome from each parent
what does meiosis result in
4 haploid daughter cells
what does meiosis 1 do
separates homologous chromosomes
when does crossing over and synapsis occur
prophase 1
what does meiosis 2 do
separates sister chromatids
mitosis vs meiosis
Mitosis: one division forming 2 identical cells (clones); Meiosis: two divisions forming 4 genetically
different cells
meiosis 2 is similar to mitosis because...
sister chromatids separate
how do different alleles occur
through mutation
what 3 things contribute to genetic variation
crossing over, independent assortment, random fertilization
when does independent assortment occur?
metaphase I of meiosis
random fertilization
any sperm can fertilize any egg
the mating of 2 true-breeding varieties
hybridization
p generation
, true-breeding parents
f1 generation
hybrid offspring of the P generation
f2 generation
offspring of the F1 generation
alternative versions of a gene
alleles
the specific spot where a gene resides on a chromosome
locus
two alleles for a heritable character separate during gamete formation and end up in different
gametes
law of segregation
organism with two identical alleles for a character
homozygote
organism with two different alleles for a gene
heterozygote
to determine the genotype, breed the mystery individual with a homozygous recessive individual
testcross
crossing two true-breeding parents differing in two characters produces ______ in the F1
generation, heterozygous for both characters
dihybrids
a cross between F1 which can determine whether two characters are transmitted to offspring as a
package or independently is called?
a dihybrid cross
law of independent assortment
each pair of alleles segregates independently of any other pair of alleles during gamete formation
do genes located near each other on the same chromosome tend to be inherited together?
yes
occurs when phenotypes of the heterozygote and dominant homozygote are identical
complete dominance
the phenotype of F1 hybrids is somewhere between the phenotypes of the two parental varieties
incomplete dominance
two dominant alleles affect the phenotype in separate, distinguishable ways
codominance
when one gene has multiple phenotypic effects
pleiotropy
what hereditary diseases are caused by pleiotropic alleles
and Answers 2024/2025
the units of heredity and are made up of segments of DNA
genes
how many chromosomes do humans have in the nucleus of their somatic cells?
46 chromosomes (23 pairs)
the two chromosomes in each pair are called...
homologous chromosomes/homologs
each pair of homologous chromosomes includes...
one chromosome from each parent
what does meiosis result in
4 haploid daughter cells
what does meiosis 1 do
separates homologous chromosomes
when does crossing over and synapsis occur
prophase 1
what does meiosis 2 do
separates sister chromatids
mitosis vs meiosis
Mitosis: one division forming 2 identical cells (clones); Meiosis: two divisions forming 4 genetically
different cells
meiosis 2 is similar to mitosis because...
sister chromatids separate
how do different alleles occur
through mutation
what 3 things contribute to genetic variation
crossing over, independent assortment, random fertilization
when does independent assortment occur?
metaphase I of meiosis
random fertilization
any sperm can fertilize any egg
the mating of 2 true-breeding varieties
hybridization
p generation
, true-breeding parents
f1 generation
hybrid offspring of the P generation
f2 generation
offspring of the F1 generation
alternative versions of a gene
alleles
the specific spot where a gene resides on a chromosome
locus
two alleles for a heritable character separate during gamete formation and end up in different
gametes
law of segregation
organism with two identical alleles for a character
homozygote
organism with two different alleles for a gene
heterozygote
to determine the genotype, breed the mystery individual with a homozygous recessive individual
testcross
crossing two true-breeding parents differing in two characters produces ______ in the F1
generation, heterozygous for both characters
dihybrids
a cross between F1 which can determine whether two characters are transmitted to offspring as a
package or independently is called?
a dihybrid cross
law of independent assortment
each pair of alleles segregates independently of any other pair of alleles during gamete formation
do genes located near each other on the same chromosome tend to be inherited together?
yes
occurs when phenotypes of the heterozygote and dominant homozygote are identical
complete dominance
the phenotype of F1 hybrids is somewhere between the phenotypes of the two parental varieties
incomplete dominance
two dominant alleles affect the phenotype in separate, distinguishable ways
codominance
when one gene has multiple phenotypic effects
pleiotropy
what hereditary diseases are caused by pleiotropic alleles
