Download Mitosis PPT

Do Now: Match the following cellular organelles to their function.
Cell Membrane
Nucleus
Mitochondria
Chloroplasts
Ribosomes
Cytoplasm
Endoplasmic Reticulum
Vacuole
1. Controls movement in and out of the cells,
5. Carries materials throughout the cell & aids in making
provides support & protection, maintains
proteins ____________________________________.
homeostasis__________.
6. Controls all cell activities & contains the DNA of the cell____.
2. Creates proteins ___________________
7. Stores food, water, and wastes. _____________________
3. Supports and protects all the cell organelles; jelly-
like substance ____________.
8. Uses energy from the sun to make plant food & site of
photosynthesis ______________________.
4. Site of cellular respiration, breaks down glucose
molecules to release energy ___________________
Mitosis
What is it? Why is it important?
Let’s review...
responsible for regulating what comes in and out of the cell, provides
★ Cell Membrane- protection & support, maintains homeostasis
controls all cell activities & contains DNA material for the cell
★ Nucleus-
site of cellular respiration, breaks down glucose to release energy
★ Mitochondria-jelly-like substance that supports & protects all the cell’s organelles
★ Cytoplasm-
Let’s review...
★ Ribosomes-
create proteins
★ Endoplasmic Reticulum-
aids in making proteins, carries materials throughout the
cell
site of photosynthesis; uses sunlight to create food
stores food, water, and waste
★ Chloroplast-
★ Vacuole-
Let’s review...
★ Lysosome-
uses enzymes to break things down in the cell
★ Golgi Apparatus-
combines and packages smaller materials into more complex
molecules; either sends them throughout the cell or stores them
Mitosis
What is it?
process where a single cell divides into two IDENTICAL daughter cells
What is the main goal of mitosis?
cell growth & to replace old, worn out cells
Why is mitosis so important?
replaces non-sex cells needed for growth and development
grow body parts, develop, repair damaged tissues, replace dead cells
and change at a cellular level as they mature.
Why do we need more cells?
all species came from a single cell
cell division allows cells to grow and multiply, so we can grow and
develop
zygote- fusion of a sperm cell and an egg cell (2 haploid cells)
starts as a single cell, then rapidly divides causing growth
Binary Fission
unicellular organism divides into 2 identical daughter cells
form of asexual reproduction
duplicates DNA
plasma membrane is drawn inwards & deposits new cell wall material
divides into two daughter cells
each cell receives a copy of the DNA
primary reproduction method in prokaryotes
does not require genetic contributions from two parents
IDENTICAL!
QUIZ!
● What happens to the size of bacteria after
binary fission?
● What must occur before binary fission?
● What benefit(s) do bacteria derive from binary fission
(as opposed to sexual reproduction)?
Eukaryotic Cell Cycle
cell cycle- sequence of growth, replication, and division that produces new cells
eukaryotes have 22 sets of autosomes (non-sex chromosomes) and 1 set of
sex chromosomes → 23 sets all together
designated with X (female) & Y (male)
a person’s cells have 46 chromosomes all together
diploid- carry two sets of chromosomes
designated as 2n ---- scientists use “n” to represent a set of chromosomes
haploid- carry one set of chromosomes
Nucleus
nucleus must first divide before the rest of the cell can
the genetic material must be copied, checked for errors and mutations, and then
packaged into chromosomes
cell cycle usually lasts 24 hours
Stages of Mitosis
Interphase
G1 phase (first gap)... 11 hours
S phase (synthesis of DNA)... 8 hours
G2 phase (mitosis and cytokinesis...4 hours
M Phase-Mitosis….1 hour
prophase
metaphase
Interphase
G1 Phase
cell growth occurs
increase in cell size
duplicates organelles
S Phase
DNA synthesis
chromosomes are replicated, joined together to form a sister chromatid
occurs in nucleus
Prophase
early prophase- chromosomes condense
late prophase- nuclear envelope begins to dissolve & centriole pairs move apart
centriole-small, cylindrical organelle near the nucleus; involved in the development of spindle
fibers used in cell division (pairs=centrosome)
spindle fibers- attach to chromosomes and pull them apart
Metaphase
pairs of sister chromatids line in a single row along the metaphase plate
spindle fibers attach to the Kinetochore or centromere (on chromosomes)
Anaphase
connections between the pairs of sister chromatids are broken
sister chromatids separate and individual chromosomes move towards the
poles
Telophase
chromosomes decondense
nuclear envelope reforms
Cytokinesis
formation of cleavage furrow- constricts like a drawstring to separate the cells
cytoplasm divides
in plant cells...a cell plate forms that leads to a cell wall
Mitosis produces identical offspring (2n… 2n)
Remeber...
I Picked Many Apples
Today..Cool!
QUIZ! Name the stage of mitosis