Maahi's Biology Connections

Nucleic Acids

Mitosis

Cyclins control the progression of the cell cycle by binding to Cyclin Dependent Kinases (CDKs)

Transcription

Synthesis of an RNA sequence from DNA template

occurs in the nucleus

Translation

Polypeptide chain released from Exit site is inactive so it begins folding

Base Pairing

Two nitrogenous bases bound to each other by hydrogen bonds

Cytosine ≡ Guanine

Adenine = Thymine (DNA)/Uracil (RNA)

Molecular Biology

Steroids

Cholesterol

Lipids

phospholipids: glycerol + 2 fatty acids + 1 phosphate group

Proteins

Responsible for most of the human body functions

Metabolism: anabolism and catabolism

Regulation in body

Homeostasis: self-regulating process cells conduct to maintain stability while adjusting to changing external conditions

Enzymes are proteins

Hydrogen Bonds

Connects nucleotides in DNA (CG/TA)

Protein Folding: stabilizes the 2°, 3° and 4° structure in proteins

Carbohydrates

Structural support to plant cells and fungi (cell wall)

Cell Biology

Ultrastructure of Cells

Ribosomes: synthesize proteins and translate mRNA

Cytoplasm

Contains enzymes to catalyze the reactions that take place

Membrane Transport

Exocytosis and Endocytosis

Help regulate the cell shape change during cell division due to CDK

Cell Membrane

cholesterol reduces membrane fluidity and permeability

made up of phospholipids (hydrophilic heads and hydrophobic tails)

Organelles

Centrioles: release spindle fibers that pull chromosomes apart

Eukaryotes

Multiple linear DNA molecules packaged with histone proteins (globular and wider than DNA forming nucleosomes)

Prokaryotes

One chromosome consisting of a circular DNA molecule made of naked DNA

May have additional plasmids to contain genes, often related to specific function

Cell Theory

Cell Division: cells are only formed through the division of other cells

Genetics

Genes

Most genes encode proteins but some don't (tRNA)

Genetic Modification

Insulin (hormone that controls blood sugar levels) can be obtained from the plasmid of E.coli

Meiosis

Chromosomes

DNA coils around histones (proteins) forming nucleosomes which supercoil into chromosomes