Test 4 bio 110
In a human cell at prophase I, there are ____ tetrads
23
Mendel's principle of segregation states that:
Alleges separate from each other before forming gametes
______ are alternative forms of a gene that govern the same feature, such as eye color, and occupy corresponding positions on homologous chromosomes.
Alleles
Cytokinesis in plant cell mitosis accurs initially by the formation of a
Cell plate
What evolutionary advantage is provided by sexual reproduction?
Increased genetic diversity
The Cell cycle of a typical somatic cell consists of ________ and M phase
Interphase
Chromosomes are duplicated during ____ of the cell cycle
S phase
cytokinesis in animal cells involves contraction of a ring of _____ microfilaments
actin plus myosin
A zygote contains the _____ complement of chromosomes
diploid
The chromosome makeup of an individual organism is called a:
karyotype
sporophyte plants produce spores using:
meiosis
gametophyte plants produce gamete using
mitosis
Using standard conventions for naming alleges, which of the following pairs is correct?
tt- homozygous Tt- heterozygous TT- homozygous
A Bacterial Chromosome consists of
A circular DNA molecule many times larger than the cell
The physical location of a particular gene on a chromosome is called:
A locus
To prevent disastrous consequences, the eukaryotic cell cycle is controlled by:
A series of cell cycle checkpoints
The separation of alleges of a gene takes place during:
Anaphase I of meiosis
Which of the following represents the possible genotype resulting from a cross between an individual homozygous and one heterozygous individual:
BB and Bb
During prophase, ______ is (are) compacted into visible chromosomes.
Chromatin
If meiosis did not occur in sexually reproducing organisms, then:
Chromosome number would double in each generation
The sources of genetic variation during meiosis are:
Crossing-over and the random assortment of maternal and paternal chromosomes
The kinetochore serves which of the following functions?
Kinetochores regulate the length of the cell cycle
The M phase of the cell cycle involves two main processes:
Mitosis and cytokinesis
The term dominant means that
One allege can mask the expression of another in a hybrid
Mating a true-breeding pink rose plant with a true-breeding pink rose plant will produce:
Only plants with pink roses
Mendel verified true-breeding pea plants for certain traits before undertaking his experiments. The term true breeding refers to
Organisms that will produce identical copies of themselves upon reproduction
During which phase does crossingover occur
Prophase I
If a cell is dividing by binary fission then you know that:
The cell is prokaryotic
A cell is in metaphase if
The chromosomes are aligned at the midplane of the cell
Most human somatic cells are:
diploid
The mitosis spindle is made of:
microtubules
The formation of female gazettes is termed
oogenesis
Which of the following are produced by meiosis
polar bodies, animal eggs, animal sperm, and plant spores
During prophesy I of meiosis, homologous chromosomes lie side by side. This phenomenon is known as:
tetrad formation
nucleosomes are best described as
Eukaryotic DNA associated with histone proteins
Animal cells are stimulated to divide by mitosis by
Growth factors
During prophase I, each chiasma represents
A site of crossing-over
The ____ is responsible for the separation of the chromosomes during _____ of mitosis
Mitotic spindle; anaphase
Which of the following represents the sequence of events during mitosis
Prophesy- metaphase- anaphase- telophase
____ contain identical DNA sequences and are held together by _____ during mitosis
Sister chromatids; centromeres
Mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of
Test cross
All of the following events occur during prometaphase except:
The duplicated chromosomes become visible with the light microscope
In genetics, map units express the distance between:
Two loci on a chromosome
A ____ is best used to demonstrate the linkage of two genes.
Two- point test cross
During which of the following stages of meiosis do the sister centromeres separate
anaphase II
Duplicated centrioles move to opposite poles of a dividing ____ cell during _____ of the cell cycle
animal; prophase
The correct number of chromosomes is maintained during sexual reproduction by:
meiosis, which reduce the chromosome number by half
The physical appearance of an organism for a given trait is termed
phenotype
Homologous chromosomes undergo synopsis during:
Prophase I
If a cell is in G2
It lacks a visible nuclear membrane