Molecular Cell Biology: Life Begins With Cells PDF

## Molecular Cell Biology: Life Begins With Cells ### Order of Cells - Order - Evolutionary Adaptions - Regulation - Response to Homeostatistic Enviroment - Energy - Reproduction - Processing - Growth & Development ### Cells - Small membrane-bounded compartments filled with concentrated aqueous...

## Molecular Cell Biology: Life Begins With Cells ### Order of Cells - Order - Evolutionary Adaptions - Regulation - Response to Homeostatistic Enviroment - Energy - Reproduction - Processing - Growth & Development ### Cells - Small membrane-bounded compartments filled with concentrated aqueous solution of chemicals - Simplest form of life are solitary cells that reproduce by dividing in two - Higher organisms (humans) -> cellular cities where groups of cells perform specialized functions ### Cells: A "Sac" - Surrounded by the membrane with gates (proteins & lipids) - Lipids: fatty acids composed of carbon, hydrogen and carbon dioxide - Carboxylic acid - Lipids contain little amounts of oxygen in the "head" - Proteins are composed of amino acids used for structural support ### Modern Cell Theory - Cells are the structural and functional unit of all living things - Come from pre-existing cells by division - Contain DNA passed from cell to cell during division - Composed of 6 elements -> C, H, O, N,P,S - Energy flow (metabolism) of life occurs - Plasma membrane: permeable to specific molecules that a cell needs - Transport proteins in cell membrane allow selective passage of molecules - Each transport protein is specific to a certain molecule ### Major Components of A Cell - 70% H2O - most abundant molecule, inorganic ions, & carbon-containing - Nucleic acids: deoxyribonucleic (DNA) & ribonucleic acid (RNA) - Proteins - Simple & Complex Carbohydrates - Lipids & Organelles - Digest quick & spike blood sugar faster - Eg. white bread - Digest slower & release glucose into the blood stream slower - Eg. whole-grain bread ### Organelles - Orderly arrangements of molecules -> Produce energy - Eg. Mitochondrian - Animals & Chloroplasts - Plants ### Different Types of Cells - **2 Types of Cells:** - **Prokaryotic:** DNA not separated from the cytoplasm - Bacteria & archaea (single cells) - **Eukaryotes:** DNA is partitioned off in its own membrane - nucleus - Some are free living single celled & some are part of multicellular organisms. - **Similarities:** Chromosomes, DNA as genetic material, Ribosomes, Cytoplasm, Plasma Membrane, Vacuoles ### Types of Microorganisms - Bacteria - Fungi - Virus - Prions - Parasites - Protozoans ### The Evolution of the Cell - Natural selection involves 2 processes: - Random variations are passed from an individual to its descendant. - Selection in favour of genetic info helps to survive & propagate. ### From Molecules to the First Cells - Organic molecules in cells: amino acids, sugars, purines & pyrimidines to make nucleotides - DNA, RNA, Proteins are made of: H, C, N, O, S, P - Amino Acids & Nucleotides associate to form Polymers -> Polypeptides (protein), polynucleotides (DNA, RNA), polysaccharides (carb) - Polyneucleotides: direct their own synthesis - Self-replicating molecules: undergo Natural Selection - RNA can catalyze biochemical rans. - Info flows from polynucleotides to polypeptides - DNA = hereditary material - Friedrich Wohler (1800-1882) synthesis of urea - Proteins: 20 types of amino acid - Phospholipids: fundamental building blocks of ALL cell membranes - Oil-water interface -> hydrophillic head & lipophilic tail (head in water, tail in all) - Polypeptides: Proteins, Polynucleotides: DNA/RNA, Polysaccharides: Carbohydrates - Nucleus is covered by: outter & inner nuclear membranes (ONM & INM) & surrounded by cytoplasm where organelles float ### How are cells studied - Microscopes: Electron microscopes -> higer magnification, higher resolution, more detail compared to light microscopes - R.Hook: discovered new world in cells using microscopes ### Classifications of Living Things: Domains of Life - **3 Domains:** - **Bacteria:** domain & kingdom - **Eukaryota:** Kingdoms: Fungi, Plants, Animals, Protists (single-celled) - **Archea:** Domain & Kingdom