Cell Growth & Division 10-1 and 10-2

Interphase

- between cell divisions - a period of growth that consists of G1, S, and G2 - DNA is replicated and chromosomes are always in the form of chromatin - Nuclear membrane and nucleolus present - Most of cell cycle spent here

Mitotic (M) Phase

10% of a cell's life where the DNA and cytoplasm are divided into 2 new cells.

How many cells are there in an adult?

100 trillion

Sister Chromatids

2 of the same chromosome joined together; will be pulled apart in cell division DNA is in this form only when a cell is dividing it's nucleus.

What is the size of a cell?

2-200 micrometers

What is the symbol for diploid?

2n

Mitosis - diploid # of chromosomes

46

What is interphase and name the percent of the cell's life:

90% of a cell's life where it grows and replicates DNA in preparation for cell division.

Carcinogen

A cancer-causing substance

Carcinogens

A substance that can cause cancer by damaging DNA or disrupting cell functions

Mutagen

A substance that can cause genetic (DNA) mutations.

Sexual Reproduction

An individual is created when two haploid gametes (sex cells) join together during fertilization.

What are the two proteins that help control and monitor cell division?

CDK and Cyclin

Metaphase

Chromosomes line up in the middle of the cell, each chromosome is attached to spindle by its centromere

Chromosomes

Condensed chromatin, there are 23 pairs of chromosomes one lone piece of double stranded DNA coiled into a rod DNA is in this form only when a cell is dividing it's nucleus.

What makes a cell divide?

DNA

Binary Fission

DNA is replicated, cell pinches inward, splitting cell in two, bacteria are the only organisms to reproduce this way

Before a cell will divide, it will replicate all of its _____ so that the two new ____________ cells will have its own set of ______.

DNA, daughter, DNA

Cytokinesis

Division of the cytoplasm during cell division

What are the subphases of interphase?

G1, S, G2

_________ is the division of the nucleus and its contents to two daughter cells.

Mitosis

Centromeres split and SISTER CHROMATIDS pull apart.

Mitosis Anaphase

CYTOPLASM and cell splits into TWO DAUGHTER cells. Dipoid # for cell = FOUR chromosomes

Mitosis Cytokinesis

Cell GROWS & prepares for division. DNA & organelles are DUPLICATED Substages: G1, S, G2

Mitosis Interphase

Chromosomes line up in the MIDDLE of the cell.

Mitosis Metaphase

Chromatin condenses to CHROMOSOMES Centrioles form the MITOTIC SPINDLE Nuclear membrane & nucleolus disappears

Mitosis Prophase

Chromosomes uncoil back to CHROMATIN Nuclear membrane & nucleolus reform. MITOTIC SPINDLE disappears.

Mitosis Telophase

What forms during mitosis to help pull chromosomes apart?

Mitotic spindle

What is the symbol for haploid?

N

Asexual Reproduction

New individual's are created when a parent cell makes an exact copy of itself Examples = Mitosis, Binary Fission, Budding

Gene

Piece of DNA that codes for a specific trait Composed of EXONS (coding DNA) and INTRONS (non-coding DNA)

What cells are produced in mitosis? (another name, and examples)

Somatic cells and body cells ex: skin cells, liver cells, lung cells

Chromatin

Strands of DNA wrapped around proteins. thin uncoiled DNA is in this form for about 90% of a cell's life.

What cell would you be and why?

The smallest cell - it has a greater SA:V ratio, so it can move nutrients and wastes more easily across the cell membrane.

Gap 1 Phase (G1)

a period of growth for the cell.

Mutations

can change survival or reproduction rate of species

If the cell reaches a point where it can no longer handle the amount of growth that has occurred during the cell cycle, it will go through __________.

cell division.

Gap 2 Phase (G2 Phase)

cell grows & prepares for cell division.

Animal cells have __________________________ to form the spindle. Plant cells do not have centrioles and use the ________________________ to form the spindle.

centrioles, cell membrane

Anaphase

centromeres splits and spindle fibers shorten separating sister chromatid, after separation each chromatid is now called a chromosome, chromosomes move to opposite poles, away from their copies

Cytokinesis in Animal Cell

cleavage furrow where the membrane and cytoplasm pinch in to split the cell into two, mitotic spindle is formed with the help of centrioles

What is the division of the cytoplasm and end of mitosis?

cytokinesis

In Mitosis, cells are _______ (2N) which mean they have the ___ set or ___________ the number of chromosomes.

diploid, full, double

Pathogens

disease causing agents

Prophase

first and longest phase of mitosis, nuclear membrane and nucleolus disappear, replicated DNA in the form of chromatin, coils form to chromosomes

What's the difference between growth and division?

getting bigger vs. reproduction

What is cell growth?

getting bigger, gaining mass

Why do cells divide?

growth, repair, reproduction

Why is mitosis important?

helps replace damaged cells, helps grow and develop

Centromere

holds chromosomes together

In Mitosis, cells are __________ because they have the ____ number and type of chromosomes as the original cell.

identical and same

The new cells are genetically ____________ to the parent cell. They will each have the ______ number of chromosomes as the parent cell.

identical, same

Limits To Cell Growth: The _____________ a cell becomes, the more ________ there is on a cell and on a cell's DNA. As a cell gets larger, the ratio of _________________ to _____________ will decrease.

larger, stress, surface area, volume

Fertilization

male & female gametes combine to create a diploid zygote

Limits To Cell Growth: It will take ____________ for nutrients and waste to move from the cell membrane to the interior of the cell and vice versa (think large city vs. small city - which has faster moving traffic?)

more energy

Telophase

nuclear membrane and nucleolus reappear, chromosomes become chromatin, spindle starts to disappear, two daughter cells are formed

In mitosis, the parent cell divides _________ and produces ______ daughter cells.

once and two

Mutagen example

radioactive substances and carcinogens

Synthesis Phase (S)

replication and synthesis of DNA.

Limits To Cell Growth: It is better to be a _________ cell than a ____________ cell because needed materials can be moved more ___________ and requires less ____________ (more cell membrane to move things, but less volume to have to move it through.

small, large, quickly, energy

If our cells are always dividing, why don't we have more?

some die and are damaged

When each chromosome pairs with its homologous chromosome in meiosis I they form a _________. Once tetrads form, _______________ occurs and shuffles DNA between the chromosomes.

tetrad and crossing over

Cytokinesis in Plant Cell

the cell plate forms at the center and expands to the outside of the cell and this structure forms the cell wall

Cell Cycle

the life cycle of a cell

Budding

tiny growth off the side of a parent that eventually grows to a full size, ex: yeast, hydra

example of a carcinogen

tobacco, products, some viruses, DDT

What will happen if the cell cycle isn't controlled?

tumors and cancer could develop

Sporulation

use spores to reproduce examples: fungi-mold, mildew, mushrooms plants- ferns, mosses

Pathogen Examples

viruses, bacteria, protists, fungi, animals

Cell Division

when a cell splits to create two, new identical daughter cells.