DNA, RNA, Protein Synthesis and Meiosis and Mitosis

Mitosis, Meiosis Basics, SOL review, IBMYP

Gene’s Role

1. Carrying information from one generation of organism to the next

2. Must be able to use the information they produce to create trait’s of an organism

3. A mechanism of easily copying the gene, so information replicates every time a cell divides.

DNA

Consist of Nucleotides.

Nucleotides

Monomer of Nucleic Acid: Made up of phosphate groups, nitrogen bases and 5-carbon sugars

Nitrogen Bases→Nucleotides→DNA→Genes→Trait’s of an organism

Purines

Double Ring structures (nitrogen bases): Adenine and Guanine

Pyrimidines

Single ring structures (nitrogen bases): Cystonine, Thymine and Uracil

Erwin Chargaff

Created Base Pairing (Chargaff’s Rules)

Rosalind Franklin

Used x-ray diffiraction to recorded the scattering pattern of x-rays on film. Suggested that DNA was a two strand-helix structure, nitrogen bases at the centre of the molecule.

Watson and Crick

Used Rosalind’s module-built a model of the structure of DNA and how it carried information and copied. Describe DNA molecule as double helix and it consisted of two strand wound around each other

DNA replication

Enzyme, Helicase splits and unzips two complementary strand and enezyme DNA polyemarase adds new nucleotides according to Base Pairing Rules. Nucleotides sealed back together by hydrogen bonds.

Gene expression: 

The process by which DNA makes proteins.

The Genetic Code

The order in which the amino acids are joined determines the type of protein made. 

Central Dogma of Biology

DNA→ transcripts→ RNA→ translates→ Protein

Prophase

DNA condenses into chromosomes in nucleus

Metaphase

Chromosomes line up in the middle of the cell, connected to spindle fibers at the centromere

Anaphase

Chromosomes are pulled apart to opposite ends of the cell by the spindle fibers

Telophase

The new cell membrane starts to form, nucleus starts to form

Difference Between Mesosis v Mitosis

Meiosis produces gametes or reproductive cells and during mitosis one introduces genetic variation-the copies of genes swapping in a chromosome during prophase.

• The daughter cells at the end of meiosis the cells are genetically different and called haploids (n). (one copy of each chromosme

Difference between Mitosis V Meoisis

Mitosis produces stomatic or body cells through asexual reproduction, only goes through one cycle of PMAT. There is no genetic variation and forms identical cells called diploids (2n). ( two indentical copies of each chromosome

Cyclins

Family of Proteins that regulate the timing of the cell cycle.

• Internal regulators

• External regulators. (control speed of cell cycle)

Cell cycle stages

G1→S→G2→M

G1- Preps for cellular growth

S Phase- DNA replicates

G2- Preparation for mitosis

M- Mitosis

Interphase

• The longest part of the cell cycle the cell acquires nutrients, creates and uses biomolecules, and prepares for cell division

Cytokinesis

The cytoplasm divides between the two new cells