Mitosis
Order the cell cycle phases in the correct order starting with the part of the cycle where normal cellular metabolism occurs
G1 to S to G2 to M
If an organism has identical alleles for one trait of interest, this organism is ______
Homozygous
True or False: In meiosis, the cells produced at the end are genetically identical to the cell at the beginning?
False
The life cycle of a sexually reproducing organisms includes what
Mitosis, meiosis, and fusion of the gametes.
Beginning with a fertilized egg cell (zygote), how many cells would be present in an embryo following a series of five cell divisions?
32
The cell cycle is regulated at the molecular level by a set of proteins known as
Cyclins
All seven of the pea plant traits studied by Mendel obeyed the principle of independent assortment. What does this indicate about those traits?
All of the genes controlling the traits behaved as if they were located on different chromosomes
During meiosis, which phase does crossing over occur?
Prophase I
Describe the differences between sexual and asexual reproduction
In sexual reproduction, offspring vary genetically from their siblings and both parents
A cell in G2 of the cell division cycle contains 20 chromatids. How many centromeres are present in this cell?
20
Just prior to cytokinesis, the cells has completed which phase of the cycle?
Telophase
When crossing an organism that is homozygous recessive for a single trait with one that is heterozygous for the same trait, what is the chance of producing an offspring with the homozygous recessive phenotype?
50%
A diploid organism has 40 chromosomes, how many homologous chromosomes would be present in gamete?
20, gametes are haploid
______ does not involve the fusion of gametes and does not add genetic variability to the population.
Asexual reproduction
Somatic cells in elephants have 56 chromosomes. How many chromosomes would be carried by the gametes produced by elephants?
28
When a cell is in late anaphase of mitosis, what may be observed?
a clear area in the center of the dividing cell
Cystic fibrosis affects the lungs, the pancreas, the digestive system, and other organs, resulting in symptoms ranging from breathing difficulties to recurrent infections. What term best describes this expression of phenotypes?
Pleiotropy
The major organizational events that set up differences between mitosis and meiosis occur in the ______ phase
Prophase
If nondisjunction of chromosome A occurs in meiosis I, what is the chromosomal outcome of A in the gametes?
½ would have three copies, the other ½ would have one copy
What will be the result if a eukaryotic cell completes mitosis but does not undergo cytokinesis?
One cell with two nuclei, each identical to the nucleus of the parent cell
Which of the following does not occur during mitotic phase of the cell cycle? Replication of the DNA, condensation of the chromosomes, separation of sister chromatids, spindle formation
Replication of the DNA
In certain plants, the tall trait is dominant over the short trait. If a plant heterozygous for the tall trait is crossed with a homozygous tall plant, what is the probability that the offspring will exhibit the short trait?
0%
During ______________________ of meiosis, cross-over events can occur when genetic material is shared between homologous chromosomes
Prophase I
If nondisjunction of chromosome A occurs in meiosis II, what is the chromosomal outcome of A in the gametes?
½ would have one copy, ¼ would have three copies, and ¼ would have one copy
If a mutagen (something that induces a mutation, ie UV light) alters the DNA in a somatic cell and that cell divides prior to the mutation being fixed, one or both of the daughter cells will inherit the mutation. If this mutation occurs in a gene that for a cell cycle checkpoint control protein, what outcome might you expect as a result of this mutation
The cell may become a tumor because it can divide unchecked