Cell Division and Mitosis

9/24/2020

Cell Division and Mitosis

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How Cells Divide

Cells divide to produce more identical cells with the same genes, this is how tissues grow and regenerate, this process is called mitosis.

Mitosis

A type of cell division that results in two cells, each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.

Book Vocabulary Words:
pg 147

Gene

A sequence of DNA that contains the information to make at least one protein

Gene Expression

The process of using DNA instructions to make proteins.

Genotype

Genetic makeup of an organism

Phenotype

The physical qualities of an organism including observable or not observable traits

Alleles

Alternative versions of the same gene that have different nucleotide sequences.

Zooming into DNA

Tissue

An organized group of different cell types that work together to carry out a particular function. Different types of cells make different tissues.

There are Many Cell Types:

Bone Cells
Blood Cells
Muscle Cells
Fat Cells
Skin Cells
Nerve Cells
Endothelial Cells

Stem Cells

Immature cells that can divide and differentiate into specialized cell types

Brain stem cells can become neural cells
Heart stem cells can become cardiac muscle
Bone marrow stem cells can become red blood cells

https://www.medacess.com/about-stem-cells/bone-marrow-derived-stem-cell.html

Cells are constantly replicating

Cell Division

The process by which a cell reproduces itself; it is normal and essential for growth and healing of tissues

Sister Chromatid

One or more identical DNA molecules that make up a duplicated chromosome following DNA replication

Centromere

The specialized region of a chromosome where the sister chromatids are joined

Cytokinesis

The physical division of a cell into two daughter cells

https://www.genome.gov/genetics-glossary/Chromatid

https://letstalkscience.ca/educational-resources/backgrounders/what-mitosis

Stages of mitosis

Interphase:

Each chromosome replicates in interphase
Resulting in two sister chromatids connected at the centromere.
Chromosomes are loosely gathered in the nucleus

Prophase:

Replicated chromosomes begin to coil up
The nuclear membrane begins to disassemble
Protein fibers of the mitotic spindle begin to form

Prometaphase:

chromosomes condense (shorten) so they are easier to separate
spindle fibers attach to chromosomes on both sides at the centromere region

Metaphase

spindle fibers from opposite ends of the cell pull on chromosomes
chromosomes are aligned along the middle of the cell

Anaphase

spindle fiber shorten and pull sister chromatids to opposite ends of the cell

Telophase

an identical set of chromosomes reaches each pole
spindle fiber dissemble
nuclear membrane forms around each set of chromosomes forming the daughter cell nuclei

Interphase

two identical daughter cells are formed, each with the same number of chromosomes as the parent cell

https://socratic.org/questions/what-are-the-order-of-the-phases-in-mitosis

Meiosis

https://socratic.org/questions/589fd775b72cff178533a701

Cell Division , electron microscopy, we will look at min 6:06 to 8:55

Meiosis

Meiosis: A specialized type of cell division that generates unique haploid gametes. Generates sex cells.

Gamete: specialized reproductive cells that carry one copy of each chromosome, sperm are male gametes, egg are female gametes

Haploid: having only one copy of every chromosome

Exchange of genetic material, new gene combinations are formed on chromatids (recombination), all four haploid daughter cells will be genetically distinct (sister chromatids are no longer identical).

https://ib.bioninja.com.au/standard-level/topic-3-genetics/33-meiosis/crossing-over.html

motor proteins

Stem Cells

Adult Stem Cells (Somatic Stem Cells)

Stems cells located in tissues that help maintain and regenerate those tissues

Multipotent

A cell with the ability to differentiate into a limited number of cell types in the body.

Embryonic Stem Cells

Stem cells that make up an early embryo which can differentiate into nearly every cell type in the body

Pluripotent

A cell with the ability to differentiate into nearly any cell in the body.