In large animals how long can nerve cells get?
1 meter
What is the largest single cell?
Ostrich Egg
How large are most cells?
2 - 200 μM
Chromosomes
The carriers of genetic material; passed on from generation to generation
Chromatinm
Stands of DNA wrapped around protein structures; long, threadlike
What does chromatin do before forming chromosomes?
Coils, shorts and thickens before cell division
What phase does a cell spend most of it’s time in?
Interphase
What happens in interphase?
Cell grows in size, centrioles replicate, and DNA is duplicated.
What happens in Mitosis?
Process of nuclear division followed by division of the cytoplasm.
Cytokinesis
Division of the cytoplasm
What happens in the prophase of Mitosis?
1) Chromatin coils into visible chromosomes
2) Nuclear envelope disappears
3) Centrioles move towards poles
What happens in the metaphase of mitosis?
1) Chromosomes meet in the equator
2) Spindle fibers attach to each chromatid at the centromere
What happens in the Anaphase of Mitosis?
1) Centromeres split and sister
2) Chromatids are pulled apart to the opposite ends of the cells (poles)
What happens in the Telophase of Mitosis
1) Cytoplasm divides
2) Nuclear envelope appears
3) Chromosomes uncoil
Parts of a Chromosome
Sister Chromatids
Centromere
Sister Chromatids
2 halves, left vs. right, of a chromosome
Centromere
Where the 2 chromatids are joined
Cancer
An uncontrolled division of cells caused by failure to produce or over production of a certain enzyme.
Gene
Segment of DNA that controls the production of protein.
Unwound DNA is called
Nucleosomes
Pieces of protein that DNA will grab and take the DNA to compress tighter
Histone
Diffusion
Takes faction of a second for glucose or oxygen to get across the plasma membrane.
Centimeter of a meter
1/100
Millimeter of meter
1/1000 of a meter
Micron of a meter
1/10000 of a meter
3 reasons why cell size is limited
Diffusion - it’s random and it could takes weeks to get certain things across plasma membrane.
One nucleus - some cells have many nuclei; Giant amoeba has 1,000 nuclei because of the way their formed/ the way they move
Volume increased more quickly than the surface area
If your surface area increased by 2 what does your volume increase by?
8
What happens if a cell gets too big?
You would die.
Man has what chromosomes
XY
Women have what chromosomes
XX
2(23) 23 from mom, 23 from dad.
46 chromosomes total
Ploids are
Sets
Diploids are
2 sets
Humans are Diploids meaning?
You have 2 sets of chromosomes. 2(n) is commonly known
How many chromosomes does a dog have?
78!
Total number of chromosomes always have to be
Even numbers
2,4,6,8,10,26,98,106
Anaphase
Pulling apart of chromosomes
In bacteria DNA isnt ____
Bound by a membrane
When DNA is in the form of a chromosome it cannot
Unzip
How long does the first phase take in interphase
11 hours
How long does the 2nd phase of Interphase take
7 hours
How long does the 3rd phase in interphase take?
How long does the 4th phase in interphase take?
Mitosis simplified
Move DNA around and split into 2 cells.
Cytokinesis means
Movement of cells
Cytokinesis; do plants partake?
Nope
Rather than going through cytokinesis, what does a plant do?
It builds a wall; a plate
What is not part of the cell cycle?
Cytokinesis! Because plamnts do not partake.
Do I see chromosomes?
If you see the nucleus there aren’t chromosomes
If you see chromosomes then its in ___________ phase of Mitosis
Prophase, phase 1
If you see 2 chromosomes in the middle then it’s in ________ phase of mitosis
Metaphase (M for Middle, and metaphase)
Centrioles are located where?
On the edges/ poles
If the chromosomes are coming apart then its in __________ phase of mitosis
Anaphase
Opposite of Prophase
Telaphase
Melanoma
Deadliest skin cancer
Apoptosis
The regular shedding of shells
Can you catch cancer?
No
HeLa Cells are
The base of all cancer cells on the planet
Chemotherapy
Kills the cancer as well as you.. But not