Mitosis Meiosis Mendelian Genetics

Mitosis Meiosis Mendelian Genetics
Biology project
Made by Lulwah.G

Introduction
• What is mitosis?
Mitosis the second main stage of the cell cycle during which the cell
replicated DNA divides into to genetically identical diploid daughter cells
are produced.
• Miosis
Miosis is 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.

Mitosis
• The stages of mitosis:
• Prophase: The first and longest stage
• Metaphase : The second stage of mitosis
• Anaphase: The third stage of mitosis
• Telophase :the final stage of mitosis

Stages of mitosis
Interphase :
• Cell grows and caries out normal cell processes
• DNA replicates
Prophase :
• Cell chromatin tightens into chromosomes (condenses).
• Nucleus disappears
Metaphase :
• Shortest stage
• Chromosomes attach to spindle apparatus and align along
the equator of the cell.
Anaphase:
• Microtubules shortens moving the chromosomes to opposite
poles.
Telophase :
• Nucleuses reapers
• Chromosomes recondense

Meiosis
MEIOSIS 1
Interphase:
• Chromosomes replicate
• Chromatin condenses
Prophase 1:
• Pairing of omogous chromosomes occurs each chromosome concicts of two
chromatids
• The neuclear envolpe breaks down
• Spindles form
Metaphase 1:
• Homologous chromosomes line up at the equater
• Chromosome centromers attach to spindle fibers.
Anaphase 1:
• Homologous chromosomes separate and move to opposite poles of the cell.
Telophase 1:
• The spindles break down chromosomes uncoil and form two nuclei,
• The cell divides.
MEIOSIS 11
Prophase 11:
• Chrommosomes condense.
• Spindles from in each new cell.
• Spindle fibers attach to chromosomes
Metaphase 11;
• Centromeres of chromosomes line up
randomly at the equator of each cell.
Anaphase 11:
• Centomeres split
• Sister chromatids seprate and move to
opposite poles
Telephase 11:
• Four nuclie from around chromosomes
• Spindles break down
• Cells divide

Mitosis and meiosis
Miosis
One division occus during mitosis
DNA replication occurring interphase
Synapsis of homolgous chromosomes
does not ocurr
Two identical cells are formed per cell
cycle
The daughter cells are genetically
identical
Mitosis occurs only in body cells
Mitosis in involved in growth repair .
Meiosis
Two sets of divisions occur durning
meiosis
DNA replication occurs once before
meiosis
Synapsis of homologous
chromosomes occurs during prophase
1
Four haploid cells (n) are formed per
cell cycle
The daughter cells are not genetically
identical because of crossing over.
Meiosis occurs only in reproductive
cells
Meiosis is involved in the production
of gamets and proving grnrtic
variactation in organisms.

Mendelian Genetics
• Genetics : Science of heredity
• Generation, F1 and F2 generations
• F1 and F2 are two offspring generations and each
of the generations of offspring provided new
evidence in respect to inheritance and natural
variation that occurs within different organisms. F1
generation is produced by the breeding of two
parental (P) organisms whilst F2 generation is
produced by the interbreeding of two F1
generation offsprings .

Mendelian Genetics
Genes in pairs
• Allele : alternative form that a single gene may have for a
particular trait.
• Dominant : Mendels name for a specific trait that
appeared in the F1 generation
• Recessive : Mendels name for a specific trait hidden or
masked in F1 generation.
Dominance
• Homozygous : having two identical alleles
of a particular gene or genes
• Heterozygous: having two different alleles
of a particular gene or genes
Genotype and Phenotype
• Genotype: A genotype is an organism’s
complete set of heritable genes, or
genes that can be passed down from
parents to offspring
• Phenotype: genetics for the composite
observable characteristics or traits of an
organism.

SUMMARY

THANK YOU
MADE BY: LULWAH.G