DNA

Griffith’s Experiment

Discovered a ‘transformation’ factor by giving mice pneumonia, differentiating between S strain (deadly) and R strain (not deadly).

Avery et al. Experiment

Demonstrated that DNA is the transformation factor, not protein.

Hershey and Chase

Provided evidence that DNA, not protein, carries genetic information.

Nucleotides

Building blocks of DNA, made of phosphate, sugar, and a nitrogenous base.

Four types of Nitrogenous Bases

Adenine, Guanine (purines), Cytosine, Thymine (pyrimidines), with A pairing with T and C pairing with G.

DNA replication

The process where enzymes separate DNA strands, allowing complementary bases to pair.

Leading strand

The strand of DNA where replication is continuous.

Lagging strand

The strand of DNA where replication is discontinuous and involves the creation of Okazaki fragments.

Cell division necessity

Cells need to divide to allow for differentiation and to address limitations in cell growth based on surface area to volume ratio.

The Cell Cycle phases

G1 (cell growth), S (DNA synthesis), G2 (preparation for division), Mitosis (division of chromosomes), Cytokinesis (division of cytoplasm).

chromatin

DNA and proteins that make up chromosomes.

Homologous chromosomes

Pairs of chromosomes that have genes for variations of the same trait.

Centromere

The region connecting two sister chromatids.

Mitosis phases

The phases are Prophase, Metaphase, Anaphase, and Telophase.

Interphase definition

The phase encompassing all of the cell cycle except mitosis and cytokinesis.

Prophase

The longest phase of mitosis where chromosomes condense and become visible.

Metaphase

Phase of mitosis where chromosomes line up at the equator of the cell.

Anaphase

Phase where sister chromatids are pulled to opposite sides of the cell after centromeres separate.

Telophase

Final phase of mitosis where chromosomes unwind and the nuclear envelope reforms.

Cytokinesis in animal cells

The process where the cell membrane moves inward, pinching the cytoplasm into two.

Cytokinesis in plant cells

Formation of a cell plate that becomes a new cell wall.