bio final chapter 5
mitosis
2 diploid offspring cells
meiosis
4 haploid offspring cells
interphase
A cell preparing to undergo meiosis duplicates its chromosomes during
Centromere
A duplicated chromosome remains tightly paired with its partner at a region called the
Down Syndrome
A nondisjunction results in a person with an extra copy of chromosome 21 results in this
gene
A segment of DNA on a chromosome that codes for a specific trait
Pleiotropy
A single gene having multiple effects on an individuals phenotype
Autosomes
Any chromosome that is not a sex chromosome
sister chromatids
As mitosis begins, __________ are linked together at the centromere.q
Cytokinesis
At the end of the mitotic (M) phase, the cytoplasm divides in a process called _________________.
sister chromatids
Before a cell divides, it copies all of its chromosomes. While the two copies of a chromosome are attached they are called
DNA
Chromosomes contain most of the cell's blank which acts as the molecule of heredity.
Chromatin
DNA and protein together form a complex called
prophase 1
During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur?
nondisjunction
Error in meiosis in which homologous chromosomes fail to separate.
linked genes
Genes located on the same chromosome that tend to be inherited together in genetic crosses.
incomplete dominance
If a woman with curly hair and a man with straight hair have a child with wavy hair, the gene for this characteristic of hair shows __
dominant
If an organism has two non-identical versions of a gene, the one that is expressed in the organism is called the this allele.
recessive
If an organism has two non-identical versions of a gene, the one that is not expressed in the organism is called the this allele.
g and k
Imagine that five hypothetical genes are arranged on a chromosome in the following order: G--H--I--J--K. Which two genes are most likely to have a crossover occur between them?
independent assortment
Independent segregation of genes during the formation of gametes
4 haploid cells
Meiosis starts with a single diploid cell and produces
Law of Segregation
Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete
alleles
Most human genes come in alternate versions called
crossing over
Process in which homologous chromosomes exchange portions of their chromatids during meiosis.
independent assortment
Random orientation of homologous pairs of chromosomes during meiosis I result in alternative arrangements that contribute to genetic variation in offspring. This is called
chromosomes
The DNA of every eukaryotic cell is stored in one or more blank located in the nucleus
cytokinesis
The cell divides into two offspring cells, each with a complete set of chromosomes from the parent cell.
prophase
The centrosomes move away from each other and the nuclear envelope breaks up during which phase of mitosis?
telophase
The chromosomes arrive at the poles and nuclear envelopes form during which phase of mitosis?
metaphase
The chromosomes line up in the center of the cell during which phase of mitosis?
interphase
The cytoplasm doubles, increasing the overall size and volume of the cell. Chromosomes are duplicated in preparation for cell division.
mitosis
The duplicated chromosomes separate and are distributed to two offspring nuclei.
phenotype
The physical traits of an organism are called its
Genetics
The scientific study of heredity
anaphase
The sister chromatids separate and begin moving toward opposite poles of the cell during which phase of mitosis?
dihybrid cross
What do we call a genetic cross that follows two separate characters, such as pea seed color and pea seed shape?
Chromosomes must be duplicated
What must happen before a cell can begin mitosis?
sexual reproduction
What process involving cell division results in daughter cells that are NOT identical to the parent cell?
cell theory
a fundamental concept of biology states all life is cellular and all cells arise from preexisting cells
therapeutic cloning
cloning where stem cells are harvested from the cloned embryo
reproductive cloning
cloning where the embryo must be transplanted into a surrogate
genotype
genetic makeup of an organism
clones
identical genetic copies, can be done through the process of nuclear transplanting
prophase 1
in meiosis homologous chromosomes stick together in pairs.
random fertilization
source of genetic variation caused by the unlimited number of possible sperm & egg combinations
polygenic inheritance
the combined effect of two or more genes on a single character
independent assortment
the law that states that genes separate independently of one another in meiosis
heredity
the transmission of traits from one generation to the next
character
this is an inherited feature that varies from individual to individual.
trait
this is one particular variation of a character.