Bio Unit 7: Cell Cycles

Interphase (G1, S, G2, M)

growth and development between cell divisions

Cell division

Process by which a cell divides into two new daughter cells

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

Cytokinesis

Division of the cytoplasm during cell division

Cell Plate

In a plant cell, midline of dividing cells. Becomes the cell wall eventually.

Cleavage Furrow

The first sign of cleavage in an animal cell; a shallow groove in the cell surface near the old metaphase plate.

Centrioles and Centrosomes

Appear during cell division and help cell divide by pulling chromosomes apart

Spindle fibers

help pull apart the cell during replication and are made up of micrtubules

Parent cell

original cell before cell division

Daughter Cell

the two new cells that result from mitosis and cytokinesis

Gap 0

Cells are not dividing and are temporarily or permanately out of the cell cycle

Cell differentiation

the process by which a cell becomes specialized for a specific structure or function.

Apoptosis

process of programmed cell death

Stem Cells

unspecialized cells that retain the ability to become a wide variety of specialized cells

Cancer

any malignant growth or tumor caused by abnormal and uncontrolled cell division

Anchorage dependence

The requirement that to divide, a cell must be attached to a solid surface.

What is a chromosome?

A threadlike structure of nucleic acids and protein found in the nucleus of most living cells.

What do chromosomes carry?

Genetic information in the form of genes.

Histone Proteins

A simple protein bound to DNA, involved in the coiling of chromosomes

Chromatid

one of two identical "sister" parts of a duplicated chromosome

Chromatin

Clusters of DNA, RNA, and proteins in the nucleus of a cell

Centromere

Region of a chromosome where the two sister chromatids attach

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Complementary base

pairs

Pyrimidines

Cytosine and Thymine

Purines

Adenine and Guanine (2 rings)

What is a nucleotide?

A building block of DNA.

What are the components of a nucleotide?

A five

Antiparallel

The opposite arrangement of the sugar

3' end vs. 5' end

3'

5'

where the phosphate group is

Deoxyribose

A five

Double helix

two strands of nucleotides wound about each other; structure of DNA

Chargaff's rule

A=T and G=C

DNA replication

the process of making a copy of DNA

What is the term for the method of DNA replication where one strand is from the original molecule?

Semi

In semi

conservative DNA replication, what type of strand is paired with the original strand in the new double helix?

Origin of replication

Site where the replication of a DNA molecule begins.

Replication fork

A Y

DNA helicase

An enzyme that unwinds the DNA double helix during DNA replication

DNA polymerase

An enzyme that catalyzes the formation of the DNA molecule.

DNA ligase

enzyme that chemically links DNA fragments together

DNA nuclease

removes damaged regions of DNA

What is the leading strand in DNA replication?

The new complementary DNA strand synthesized continuously along the template strand.

In which direction is the leading strand synthesized?

Toward the replication fork in the mandatory 5' to 3' direction.

What is the lagging strand in DNA replication?

A discontinuously synthesized DNA strand.

How does the lagging strand elongate?

By means of Okazaki fragments.

In which direction are Okazaki fragments synthesized?

In a 5' to 3' direction.

What is the orientation of the lagging strand relative to the replication fork?

It elongates away from the replication fork.

Okazaki fragments

Short fragments of DNA that are a result of the synthesis of the lagging strand during DNA replication.

Parent DNA

original strand of DNA

Daughter DNA

new DNA