Lecture 9 Flashcards
What is cell division?
When a single parental cell goes and becomes two daughter cells
What is mitotic cell division?
Asexual reproduction for unicellular eukaryotes
What is meiotic cell division?
Sexual reproduction with the offspring are the same as the parents genetic material
Why is cell division important?
It’s important for growth, cell replacement, healing, and reproduction
What are the two requirements for cell division?
First, the two daughter cells must receive full amount of genetic material from parents
Second parents must be big enough to divide and give cytoplasmic components to daughters
What’s the first step in binary fission ?
Circular bacterial DNA is attached to the inner membrane
What is the second step in binary fission?
DNA molecules proceeded bidirectionally around the circle
What is the third step in binary fission
Two identical DNA molecules in the cell form
What is the fourth step in binary fission?
The two cells will get bigger and elongate, resulting in them separating at the DNA attachment site
What is the fifth step in binary fission
Deformation of membrane and wall materials at the midpoint
What is the sixth step in binary fission
The selfie splits resulting in two daughter cells
Description of eukaryotes
They have large and linear genomes and DNA is in the nucleus
Description of prokaryotes
Small and circular genomes and DNA is in the cytoplasm
What happens in the M phase of the cell cycle?
Parent cells divided into two cells
What happens in the interphase of the cell cycle?
It’s the time between 2M phases and cells make many preparations
How is DNA organized in a structure
DNA is organized with his histones/protein into chromatin
What is the structure of chromosomes?
They are looped and packaged chromatin’s
What are karyotype?
The number in shape of chromosome species and example is how humans have 46 chromosomes
What does it mean for something to be haploid?
A cell with one complete set of chromosome (sperm/egg)
What does it mean for something to be diploid?
A cell with two complete sets of chromosomes
In mitosis what happens during prophase
Chromosomes, condense, and ensure mirrors move to opposite sides
In mitosis what happens during prometaphase
The nuclear membrane breaks down and microtubules of mitotic spindles attached to chromosomes
What are Centromere
Location where sister chromatids connect
What are centrosomes used for?
Used for chromosome separation
For mitosis what happens during metaphase
Chromosomes align in centre of the cell
For mitosis what happens during anaphase
Sister chromatids move to opposite sides of the cell
What happens during telophase for mitosis cell division?
The de condensation of chromosomes while nuclear envelope reforms
What happens during cytokinesis for animals?
Ring of Acton filaments form in between the two cells when the ring shrinks it divides the cell into two
What happens during cytokinesis for plants?
Division is done by making new cell wall and sell plates form once the cell wall fuses it becomes two cell cells
What are the products of meiotic cell division?
And the two rounds called Miles one and 4 daughter cells are formed with half the chromosomes of the parents
What happens in prophase one for meiosis?
First, the chromosome becomes visible and then homologous chromosomes, condense, and undergoes, synapsis, and finally two pairs of chromosomes form a bivalent then chromosome shortened/thicken and nuclear envelope breaks down
What is crossing over?
Among us chromosomes undergo DNA segment exchange, which helps hold bivalence together
What happened in prometaphase one
Spindles attached to kinetochores on chromosomes
What happens in metaphase one
Humungous pears lineup in the centre of the cell performing bivalent
What happens during Anna phase one
Homologous chromosome separate sister chromatids do not
What happens in Chailu phase one/cytokinesis
Daughter cells are ready for pro face 2
What is reduction division?
When you have the number of chromosomes and daughter cells
what happens in meiosis two
It’s the same as mitosis, but nuclei and prophase 2 has half of chromosomes, not diploid
What happens for males in cytoplasmic division?
Fair division occurs with the formation of sperm
What happens in cytoplasmic division for females?
Cytoplasm is divided unequally in both meiotic divisions
