Cell Differentiation & Mitosis/Meiosis Flashcards
What is cell differentiation?
Cell differentiation produces a more specialized cell from a less specialized cell.
Example:
The proces of forming an embryo.
What is a fertalized egg in an embryo called?
A zygote, and is specific to animal and plant cells.
What is the most critical stage of development in post zygote formation?
Gastrulation; occurs when individual layers begin to form.
What does differentiation determine?
Cell differentiation determines what cell type each cell will become and occurs in the developing embryo.
Stem Cells
Stem cells are the result of cells that remain undifferentiated and there are three types: totipotent, pluripotent, and multipotent cells.
Mitosis
The process of cell duplication that results in two identical daughter cells.
Chromosomes
Chromosomes are single molecules of DNA (they contain genes). Genes contain DNA. In the DNA, is the spec ified information for the cells protein synthesis (instructions of how to make chains of amino acids). Protein is vital to the body’s functioning.
What are the general stages of mitosis in order?
Interphase, Prophase, Metaphase, Anaphase, Telophase
What 3 periods make up interphase?
G1= centrioles begin replication S= DNA is replicated G2= Final preparations for mitosis are completed and centrioles are done replicating.
Further explain the process of Gastrulation:
Gastrulation is the process that occurs in the early life of the developing embryo which gives rise to germ layers from which all organs and tissue in the human body originate.
Germ Layers
During gastrulation, a hollow cluster of cells called a blastula reorganizes into two primary germ layers: an inner layer, called endoderm, and an outer layer, called ectoderm. Because humans are something called triploblastic: the two layers interact to form a third layer called the mesoderm.
Ectoderm
Forms skin, hair, and mammary glands, as well as the nervous system.
Endoderm
The endoderm produced during gastrulation will form the lining of the digestive tract, as well as that of the lungsand thyroid.
Mesoderm
The mesoderm gives rise to the central layers of the body: bone, skeletal muscle, connective tissue, kidneys and the heart
Gametes
The cells that form new organisms via sexual reproduction. During sexual reproduction, the gamete of one individual has DNA and same for the other so when they combine they have too much DNA. Therefore, in order to reduce DNA have to go through meiosis.
When does meiosis occur?
Meiosis only occurs in gametes or fertilized eggs, depending on the species.
(Germ cells go through meiosis)
How does meiosis reduce DNA
It does so by halving the number of chromosomes.
Diploid cells
Diploid cells contain two sets of chromosomes
Haploid cells
Haploid cells contain a single set of chromosomes
What is the result of meiosis?
The result of meiosis is 4 haploid cells
Homologous
Chromosomes have homologous pairs but does not mean it is identical, it means it codes for the same genes.
What is difference in the processes of Mitosis and Meiosis?
in Meiosis, PMAT occurs two times. So Prophase1, Metaphase1, Anaphase1, and Telophase1 then Prophase2, Metaphase2, Anaphase2 and Telophase2
Prophase 1 of Meiosis
Homologous chromosomes condense and link in the process-forming tetrads. This allows crossing over or recombination to occur.
Metaphase 1
Homologous chromosomes move to the metaphase plate.
Anaphase 1
Homologous chromosomes separate, but the sister chromatids stay together (Difference compared to Mitosis)
The cell’s chromosome number is reduced by half!
Telophase 1
Cytokinesis has occurred and two haploid daughter cells result.
Prophase 2
A brief stage in which spindle fibers begin to reappear (centrosomes) and centrioles move to opposite sides of the cell.
Metaphase 2
Sister chromatids align at new metaphase plate.
Anaphase 2
Sister chromatids separate.
Telophase 2
Four haploid cells result after cytokinesis.
