A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
A type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.
A mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
Define cell cycle
The cell cycle is the series of events that take place in a cell leading to its division and duplication (replication) that produces two daughter cells.
The disease caused by an uncontrolled division of abnormal cells in a part of the body.
(Of a cell or nucleus) containing two complete sets of chromosomes, one from each parent.
(Of a cell or nucleus) having a single set of unpaired chromosomes.
The first stage of cell division, before metaphase, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears. The first prophase of meiosis includes the reduction division.
The second stage of cell division, between prophase and anaphase, during which the chromosomes become attached to the spindle fibers.
The stage of meiotic or mitotic cell division in which the chromosomes move away from one another to opposite poles of the spindle.
The final stage of cell division, between anaphase and interphase, in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed.
Explain the differences between mitosis and meiosis.
While mitosis goes through one cell cycle (PMAT) and produces two daughter cells, meiosis goes through two cell cycles (PMAT I and PMAT II) and produces four daughter cells.
What is a gamete and how is it produced?
A gamete is a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
It is produced when the haploid sperm and egg cells combine during fertilization. The production of gametes is the first step of sexual reproduction.
What happens during each phase of the cell cycle?
Interphase: DNA is duplicated
Prophase (set up): Everything is setting up for cell division, the chromosomes are becoming visible and the other materials are getting ready.
Metaphase (line up): The chromosomes line up in the middle of the cell and they fully attach themselves to long strings called spindle fibers.
Anaphase (move up): The spindle fibers contract and pull the chromosomes up and down at the same time, ripping the chromosomes into two equal pieces.
Telophase (split up): A new nuclear membrane is forming around the chromosomes in each end of the cell. The cell membrane is beginning to pinch in the middle of the cell.
Cytokinesis: The cell membrane pinches the cell into two new daughter cells.
What are the types of tumors?
Benign tumor: is not dangerous like malignant tumors; does not invade nearby tissue or spread to other parts of the body.
Malignant tumor: are cancerous and are made up of cells that that grow out of control.
What is metastasis?
The development of secondary malignant growths at a distance from a primary site of cancer.
List two ways that meiosis increases genetic variability?
- During prophase of meiosis I, the double-chromatid homologous pairs of chromosomes cross over with each other and exchange chromosome segments. This recombination allows genetic diversity by allowing genes from each parent to mix.
- Shuffling the genetic deck (when each daughter cell receives only one chromosome of each homologous pair, reducing the diploid number to haploid) in this way, the gametes resulting from meiosis II have new combinations of maternal and paternal chromosomes, increasing genetic diversity.
What is one evolutionary advantage of sexual reproduction?
What is one evolutionary disadvantage of sexual reproduction?
Inheritance of genetic illnesses, genetic diseases, etc.
Describe Mendel’s principle of the segregation of alleles.
It states that allele pairs separate or segregate during gamete formation, and randomly unite at fertilization. Four main concepts related to this principle are…
- A gene can exist in more than one form
- Organisms inherit two alleles for each trait
- When sex cells are produced, allele pairs separate leaving each cell with a single allele for each trait.
- When the two alleles of a pair are different, one is dominant and other is recessive.
Describe Mendel’s principle of independent assortment.
It states that when two or more characteristics are inherited, individual hereditary factors assort independently during gamete production, giving different traits an equal opportunity of occurring together.
In what ways does the behavior of chromosomes explain Mendel’s discoveries?
Chromosomes form on their own, without instructions from the genetic control system. In addition, chromosomes behave the way they do in order to figure out whether dominant or recessive traits would show up in the offspring.