The Cell Anatomy and Physiology

Cell Theory

The Cell Theory States: When Schleiden and Schwann proposed the cell theory in 1838, cell biology research was forever changed. The cell theory states that: When Schleiden and Schwann proposed the cell theory in 1838, cell biology research was forever changed. The cell theory states that: 1. All life forms are made from one or more cells. 2. Cells only arise from pre-existing cells. 3. The cell is the smallest form of life.

the Generic Cell

Cell Differentiation

Cytoplasmic Organelles Cytoplasm: material between plasma membrane & nucleus. Organelle: “little organ” –Carry out specific functions. –Essential for normal cell function.

Mitochondria

Ribosomes Composed mainly of protein and RNA They are the site for protein synthesis. Some are located on the outer membrane of the RER and some are free floating in the cytoplasm.

Rough Endoplasmic Reticulum The RER can best be described as a network of interconnected membranes that have ribosomes located on the The RER can best be described as a network of interconnected membranes that have ribosomes located on the

Smooth Endoplasmic Reticulum Also called SER. Contain NO Ribosomes. –Play no role in protein synthesis. Serves the following functions: –Lipid Metabolism. –Synthesis of steroid-based hormones. –Absorption, synthesis, transport of fats. –Detoxification of drugs. –Breakdown of glycogen to glucose.

Nucleus

Nucleoli –composed largely of protein and RNA

Plasma Membrane Separates intracellular fluid within from extracellular fluid outside. Fluid Mosaic Model: –Double layer (Bi-layer) of lipid molecules. –Proteins float within the bi-layer. Hydrophilic: –“Water-Loving”; charged polar head. Hydrophobic: –“Water-Fearing”; uncharged non-polar tail.

Passive Transport - requires no energy and moves with the concentration gradient Diffusion is the net movement of a substance (liquid or gas) from an area of higher concentration to one of lower concentration. The majority of the molecules move from higher to lower concentration, although there will be some that move from low to high. The overall (or net) movement is thus from high to low concentration. Eventually, if no energy is input into the system the molecules will reach a state of equilibrium where they will be distributed equally throughout the system. Diffusion is the net movement of a substance (liquid or gas) from an area of higher concentration to one of lower concentration. The majority of the molecules move from higher to lower concentration, although there will be some that move from low to high. The overall (or net) movement is thus from high to low concentration. Eventually, if no energy is input into the system the molecules will reach a state of equilibrium where they will be distributed equally throughout the system. Diffusion high concentration of dye equilibrium is reached high concentration of dye equilibrium is reached

Osmosis is the diffusion of water across a semi- permeable (or differentially permeable or selectively permeable) membrane. Osmosis is the diffusion of water across a semi- permeable (or differentially permeable or selectively permeable) membrane. In general, water moves toward the area with a higher solute concentration because it has a lower water concentration. In general, water moves toward the area with a higher solute concentration because it has a lower water concentration.

Filtration and Facilitated Diffusion Filtration is a passive transport system that depends on hydrostatic pressure. Filtration is a passive transport system that depends on hydrostatic pressure. Ex – Like a coffee filter Ex – Like a coffee filter Facilitated Diffusion Facilitated Diffusion is a passive transport system that goes with the concentration gradient but moves large molecules through the protein channels. is a passive transport system that goes with the concentration gradient but moves large molecules through the protein channels.

Great link for Passive and Active Transport Systems ology1111/animations/active1.swf ology1111/animations/active1.swf ology1111/animations/active1.swf ology1111/animations/active1.swf

Active Transport Requires the use of energy and goes against the concentration gradient Ex. Na K pump Ex. Na K pump Endocytosis Endocytosis PINOCYTOSIS – cell drinking PHAGOCYTOSIS- cell eating Exocytosis Exocytosis

Cellular Respiration Glycolysis Glycolysis Anaerobic Anaerobic Takes place in cytosol Takes place in cytosol 2 Atp 2 Atp Produces 2 pyruvates Produces 2 pyruvates Kreb’s Cycle Kreb’s Cycle Aerobic Aerobic Takes place in mitochondria Takes place in mitochondria 2 ATP, CO2,NADH,FADH2 2 ATP, CO2,NADH,FADH2 Electron Transport System Electron Transport System 32 ATP 32 ATP

Mitosis Stages Prophase Metaphase Anaphase and Telophase

Meiosis Meiosis Meiosis is divided into two parts: meiosis I and meiosis II. At the end of the meiotic process, there are four daughter cells rather than the two produced at the end of the mitotic process. Each of the resulting daughter cells has one half of the number of chromosomes as the parent cell. Meiosis Meiosis is divided into two parts: meiosis I and meiosis II. At the end of the meiotic process, there are four daughter cells rather than the two produced at the end of the mitotic process. Each of the resulting daughter cells has one half of the number of chromosomes as the parent cell.daughter cellsdaughter cells Image credit: Copyright S.L. Forsburg Used with permission. All Image credit: Copyright S.L. Forsburg Used with permission. AllForsburg

Nucleic Acids DNA – genetic code DNA – genetic code Double Stranded Double Stranded Contains base pairs Contains base pairs A-T and C-G A-T and C-G Sugar = deoxyribose Sugar = deoxyribose RNA – protein synthesis RNA – protein synthesis Single stranded Contains base pairs A-U and C-G Sugar = ribose

Replication Replication When body cells divide and DNA replicates – during Interphase When body cells divide and DNA replicates – during Interphase Transcription Transcription To make proteins - the code is read from a specific area on the DNA and copied to mRNA To make proteins - the code is read from a specific area on the DNA and copied to mRNA Translation Translation The code from mRNA is read on the ribosome and translated to the have the tRNA bring the correct amino acid for making the protein. The code from mRNA is read on the ribosome and translated to the have the tRNA bring the correct amino acid for making the protein. Replication and Protein Synthesis DNA is transcribed into mRNA which is translated into amino acids. This is