cell cycle

cell cycle stuff

Cell Division

The process in which cells split to reproduce, renew, repair, replace, or make new cells.

DNA

Genetic material, our genes. Deoxyribonucleic Acid.

Chromatin

Makes up chromosomes. Made of DNA and protein

Chromosomes

Thread-like structures in the nucleus that are made of chromatin

Genome

All of our genes. The complete set of genes present in a cell.

Chromatid

Half of a duplicated chromosome

Centromere

Where the two sister chromatids of a duplicated chromosome are connected

Line

Before duplication, chromosomes are in the shape of a..

X

After duplication, chromosomes are in the shape of an..

Interphase

90% of a cell's life. Growth, protein synthesis, and chromosome duplication occur in this phase of the cell cycle. Has 3 sub-phases.

G1

The first sub-phase of interphase or the "first gap." Where the cell grows

G0

A special phase that only some cells go to after G1. The stopping point for cells that do not divide like neurons and muscle cells

S

The second sub-phase of interphase. "Synthesis" where chromosomes duplicate

G2

The third sub-phase of interphase. Known as the "second gap." Where the cell grows more and prepares for division

Mitotic Phase

The other phase of the cell cycle. Where mitosis and cytokinesis occur as the 2 sub-phases.

Mitosis

The first sub-phase of the mitotic phase. Where the nucleus divides. Has 5 sub-phases.

Prophase

The first sub-phase of mitosis. Chromatin condenses

Prometaphase

The short in-between phase of Prophase and Metaphase. The nuclear envelope breaks up and microtubules begin to form a spindle around the chromosomes.

Metaphase

The second sub-phase of mitosis. Also the longest phase of mitosis. The chromosomes line up in the middle of the cell and kinetochores connect centromeres to the spindle poles.

Metaphase Plate

The middle of the cell where all of the chromosomes line up during metaphase

Kinetochore

A protein that connects the chromosomes to the mitotic spindle

Centrosome

The organelles that form the mitotic spindle during mitosis

Mitotic Spindle

A structure made of spindle fibers (which are made of microtubles and proteins). It is formed in the centrioles of the centrosomes and moves chromosomes around during mitosis

Spindle Poles

The ends of the mitotic spindle where microtubules attach.

Spindle Fibers

A key component of the mitotic spindle, which helps pull sister chromatids apart during anaphase. They are made of microtubules and proteins.

Asters

Short microtubules that extend out from the centrosomes. These help position the mitotic spindle.

Anaphase

The third sub-phase of mitosis. The shortest phase. Here, sister chromatids pull apart

Telophase

The fourth sub-phase of mitosis. Two new nuclei (daughter nuclei) and nuclear membranes begin to form

Cytokinesis

The second sub-phase of the mitotic phase. The cytoplasm of the parent cell divides to form two new daughter cells.

Cleavage Furrow

In the cytokinesis of animal cells, this structure forms to pinch off the two daughter cells

Cell Plate

In the cytokinesis of plant cells, this structure forms in between the two daughter cells to make a new cell wall. Made of vesicles filled with cellulose.

Asexual

The type of reproduction that involves a single cell (parent) that divides to make 2 new daughter cells

Binary Fission

Mitosis (asexual reproduction) that occurs only in Archaea and Bacteria (Prokaryotes)

1

How many chromosomes do bacteria have?

Origin of Replication

Site where the replication of a bacterial chromosome begins.

Sexual

The type of reproduction that involve two cells (parents, egg and sperm) joining to make a new cell that is a combination of the 2 original cells.

Zygote

A cell that is the combination of two parent cells via sexual reproduction. e.g. a fertilized egg

Cell Cycle Control System

A series of molecular signals which regulate and drive the cell cycle.

Checkpoints

Critical points in the cell cycle where the cell is dictated whether to either "go ahead" or "stop"

Kinases

Enzymes that activate or deactivate proteins of the cell cycle

Cyclins

Proteins that must be attached to CDKs (Cyclin-dependent Kinases) for the CDKs to be active

Density Dependent Inhibition

The instinct of cells to cease cell division if they are over-crowded

Anchorage Dependent

This type of cell (most cells) must be attached to something to grow

Cancer Cells

What type of cell is neither anchorage dependent nor reliant on density dependent inhibition. Cells that grow uncontrollably and are not restricted by the cell cycle

Transformation

When a normal cell becomes cancerous

Benign Tumor

A tumor which stays at the original site

Malignant Tumor

A tumor that metastasizes (moves to another tissue)

Radiation

A type of treatment for cancer which targets and damages cancer cell DNA

Chemotherapy

A type of treatment for cancer which is a concoction of toxic drugs that interfere with the cell cycle of rapidly dividing cancer cells

Surgery

A type of treatment for cancer which physically cuts out the cancer cells

Stem Cells

Unspecialized cells that can become many different cells through differentiation. In early development, they become every tissue in the body. Have the potential to grow new, healthy tissues to cure diabetes, Parkinson's, Alzheimer's, or heart disease

Genetics

The scientific study of heredity and heredity variation

Heredity

The transmission of traits from one generation to the next

Variation

How offspring differ from their parents and other siblings/relatives

Genes

Segments of DNA. These segments are passed from from parent to offspring

Gametes

Sex cells that carry genes from one generation to the next. e.g. eggs and sperm

Zygote

The product of a union of gametes to create a new cell. e.g. Fertilized egg cell

Embryo

An organism in the earliest stage of development. A zygote develops into this

Fetus

The stage at which a developing offspring does the most growing in the womb. An embryo develops into this. In humans, this stage typically occurs 9 weeks after fertilization to birth

Newborn

The classification of an offspring from birth to ~1 month

Karyotype

A visual representation of all 23 pairs of chromosomes arranged in order from 1–23 in terms of size

Homologous Pair

A pair of two duplicated chromosomes (XX). One from the maternal side and one from the paternal side

Autosomes

Non-sex chromosomes. Humans have 22 pairs

Sex Chromosomes

The type of chromosome that determines gender. Humans have 1 pair. Women have XX and men have XY

Diploid

2n cells. Have the total amount of 46 chromosomes. Are somatic cells or zygotes. Created from mitosis

Somatic Cells

Body cells

Haploid

n cells. Have 23 unduplicated chromosomes. Are gametes (sex cells: sperm, eggs). Created from meiosis

Meiosis

Cell division that reduces the number of sets of chromosomes from 2 to 1. Specifically creates gametes. Only occurs in the ovaries (females) and testes (males). Creates 4 daughter cells instead of 2 like mitosis

Meiosis I

Prophase I, Metaphase I, Anaphase I, Telophase I, Cytokinesis

Meiosis II

Prophase II, Metaphase II, Anaphase II, Telophase II, Cytokinesis

2

Meiosis I creates ___ daughter cells

4

Meiosis II creates ___ daughter cells

Homologous Chromosomes

In Anaphase I, the ____ pull apart

Sister Chromatids

In Anaphase II, the ____ pull apart

4

In meiosis in males, the 4 daughter cells become ___ sperm

1

In meiosis in females, ___ of the 4 daughter cells become egg(s)

Polar Bodies

In meiosis in females, the 3 other daughter cells that don't become an egg become...

Polar Bodies

One of the results of meiosis in females which support the egg cell

After Puberty

When do males start producing sperm (going through meiosis)?

Before Birth

When do females start producing eggs (going through meiosis)?

Identical

Cells that are created by mitosis are genetically...

Different

Cells that are created by meiosis are genetically...

Recombinant Chromosomes

Chromosomes that carry genes from each parent. The result of crossing over

Different

Cells that are created by meiosis are genetically...