-is composed of super coiled DNA molecule which is wound around on its associated protein. -contains all the genetic information of the organism -normal human being has 23 paired chromosomes or 46 chromosomes -Two Forms: Duplicated- contains duplicated DNA Unduplicated- DNA is not duplicated
Chromosome
is as a process by which a cell divides to form two identical daughter cells.
Mitosis
Only ______ or body cells undergo mitosis.
somatic cells
____ or sex cells (Ovum and sperm) undergo meiosis.
Gametes
Mitosis is divided into several stages:
Prophase , Metaphase, Anaphase, Telophase
-It is the growth phase; resting phase; -not considered as one of the stages of mitosis but a requisite for mitosis to occur -Duplication of the genetic material
Interphase stage:
-The chromosome condenses or coils, becoming short and thick. -The nucleolus disappears and the nuclear membrane disintegrates. -The centriole and spindle fibers appear.
Prophase stage:
-Chromosomes are aligned at the equatorial plate -The nuclear envelope has totally disintegrated and -The polar fibers have reached the centromeres of the chromosomes and have begun interacting with them.
Metaphase stage :
-The two sister chromatids separate at its centromere, and each is attached to a spindle fiber as it migrates towards the opposite poles.
Anapahase stage:
-This is the phase that is marked when the two new daughter nuclei and their respective nuclear envelopes start to reform -the chromosomes uncoil. In animal cells -division of cytoplasm or cytokinesis which starts as a cleavage furrow or indentation around the middle that eventually pinches in, dividing the cell in two.