Recall basic cell physiology

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Lorena Daniel
5 years ago
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basic cell physiology This class I will assume you know the basic functions of these structures: Smooth and rough endoplasmic reticulum

1 (a) Chemical level: a molecule in the membrane that encloses a cell (b) Cellular level: a cell in the stomach lining (c) Tissue level: layers of tissue in the stomach wall (d) Organ level: the stomach (f) Organism level (e) Body system level: the digestive system Recall basic cell physiology This class I will assume you know the basic functions of these structures: Smooth and rough endoplasmic reticulum Golgi Peroxisomes Lysosomes Mitochondria Basic structure of the plasma membrane Gazing into a cell. Peroxisome Nucleus Lysosome Golgi 1

2 Cristae Glycolysis can occur with or without oxygen Yet, aerobic respiration yields more energy from glucose and occurs in the mitochondria 2

Citric acid cycle Fermentation Electron transport chain Within the mitochondria.

3 Chemical reactions for energy Electron transport chain Citric acid cycle Glycolysis Cytosol Making ATP First, glycolysis then either: Aerobic Pathway Anaerobic Pathway Citric acid cycle Fermentation Electron transport chain Within the mitochondria... Pyruvate enters mitochondria Citric Acid Cycle matrix Electron Transport Inner membrane (cristae) 3

4 Pyruvate Acetyl-CoA Citric Acid (or Krebs) Cycle CO 2 ATP CO 2 Where does weight go when someone loses weight? Electron Transport Chain High energy electrons taken from hydrogen are transferred through a series of carriers on inner membrane ATP Synthase w/in cristae 32 ATP formed 4

Free radicals from ETC A by-product of ETC is the production of

reactive and produce free radicals, which contribute to aging and

Energy Harvest Glycolysis (from one glucose) 2 ATP 2 NADH (makes 4

5 Free radicals from ETC A by-product of ETC is the production of abnormal versions of O 2 (O 2-, O 2 -- ) These molecules are highly reactive and produce free radicals, which contribute to aging and some diseases. Energy Harvest Glycolysis (from one glucose) 2 ATP 2 NADH (makes 4 ATP in ETC) Citric Acid Cycle 2 ATP plus NADH, FADH 2 for ETC Electron Transport Chain 28 ATP by oxidative phosphorylation 5

Anaerobic conditions Aerobic conditions Lactic acid myth Lactic acid

leaves muscle, enters blood and is used elsewhere for ATP production

6 Anaerobic conditions Aerobic conditions Lactic acid myth Lactic acid (really lactate) isn t the cause of muscle fatigue and soreness Lactate leaves muscle, enters blood and is used elsewhere for ATP production (using O 2 ) Lactate threshold Interval training uses periods of training above and below the L threshold. High intensity portions stimulate your body to produce enzymes that speed the use of lactate fuel (MCT1 carrier protein) 6

Plasma membrane of cells oligosaccharide groups phospholipid cholesterol EXTRACELLULAR ENVIRONMENT (cytoskeletal proteins beneath the plasma membrane) ADHESION

PROTEINS CYTOPLASM Receptor sites (ex: endocrine sites) Cell adhesion (CAM) grips neighbor cell Channels for ions, small molecules Carrier proteins Attach to

7 Plasma membrane of cells oligosaccharide groups phospholipid cholesterol EXTRACELLULAR ENVIRONMENT (cytoskeletal proteins beneath the plasma membrane) ADHESION PROTEIN open gated gated active RECEPTOR RECOGNITION channel channel channel transport PROTEIN PROTEIN protein protein protein protein (open) (closed) TRANSPORT PROTEINS CYTOPLASM Receptor sites (ex: endocrine sites) Cell adhesion (CAM) grips neighbor cell Channels for ions, small molecules Carrier proteins Attach to cytoskeleton Membrane receptors Binding to the receptor will: Open or close channels for ions (Na +, K +, Ca ++ ) Transfer a signal to 2 nd messenger to trigger events in the cell 7

8 2 nd messenger system will activate an enzyme Other cell adhesions Extracellular matrix - Biological glue. 3 protein fibers are interwoven in this matrix: collagen, elastin, fibronectin. Secreted by cells Desmosomes Rivets to anchor adjacent cells that are not touching Other cell adhesions Tight junctions Epithelium cells form tight seal at points of contact Gap junctions - Small tunnels connect cells 8

open channel proteins gated channel proteins transport

specific substance (the solute) Passive transport

conformations high solute concentration Concentration

9 open channel proteins gated channel proteins transport protein transport protein with binding site for a specific substance (the solute) Passive transport (facilitated diffusion) protein has 2 different conformations high solute concentration Concentration gradient Active Transport phosphorylation required Direction of transport 9

Membrane (permeable to water only) Side 1 Side

gradient but water moves Water and solute

Membrane (permeable to H 2 O) Side 1 Side 2

H 2 O Pure water Gradients still exist Osmosis

Side 2 Hydrostatic (fluid) pressure difference

10 Membrane (permeable to water only) Side 1 Side 2 H 2 O Solute can t move to side 1 down its gradient but water moves Water and solute concentrations now equal Side 1 Side 2 Membrane (permeable to H 2 O) Side 1 Side 2 Solute can t move to side 1 down its gradient H 2 O Pure water Gradients still exist Osmosis is balanced by hydrostatic pressure Side 1 Side 2 Hydrostatic (fluid) pressure difference Osmosis Hydrostatic pressure Isotonic Hypotonic Hypertonic 10

Cells. Unit 3 Cell Structure and Function. Cells. Plasma Membrane

Cells. Unit 3 Cell Structure and Function. Cells. Plasma Membrane Unit 3 Cell Structure and Function Cells Cell theory The cell is the basic unit of life The cells of all living things exhibit the seven characteristics of life All living things are made of cells Cells