The Cell
Movement through the cell Passive transport – no energy required Diffusion – region of high concentration to low concentration Osmosis and dialysis – water through a selectively permeable membrane Filtration – water and small particles through system due to hydrostatic pressure Kidneys and urine formation
Active transport Requires energy (ATP) Ion Pumps Phagocytosis low to high concentration Ion Pumps Sodium potassium pumps Phagocytosis Larger molecules, foreign material Pinocytosis Fluids and dissolved material
Tonicity Isotonic Salt solution .9% is isotonic = to red blood cell Hypertonic – solution contains higher salt content than cell Water moves out of cell, cell shrinks = crenation Hypotonic - solution contains lower salt content than cell Water moves into cell, cell swells and lysis could occur
Nucleic Acid: DNA and RNA Double stranded Helix ATCG Deoxyribose Can not leave nucleus Dictates directions for protein synthesis RNA (mRNA, rRNA, tRNA) Single stranded Linear AUCG Ribose sugar Can leave nucleus Carries out protein synthesis
Protein synthesis, Fig 3.8 Transcription Translation DNA to mRNA – out of nucleus Translation mRNA to ribosome to make protein
Cell division Interphase Prophase Metaphase Anaphase Telophase G1 – growth S – synthesis, DNA copies itself G2 – preparation for cell division Prophase Metaphase Anaphase Telophase Cytokensis
Changes in cell growth and reproduction Hypertrophy – increase in size of cell Atrophy – decrease in size of cell Hyperplasia – increase in cell reproduction Increase of number of cell Anaplasia – production of abnormal, undifferentiated cells Can result in a tumor or neoplasm