Cell metabolism, transport, & reproduction

Membrane Transport Passive Transport (No energy required) Diffusion Osmosis Facilitated diffusion IMPORTANT FOR YOUR CELLS ABOSPTION OF WATER AND GLUCOSE

DIFFUSION Diffusion is a PASSIVE process Trying to reach EQUILIBRIUM The Plasma Membrane 4/3/2019 DIFFUSION Diffusion is a PASSIVE process no energy is used to make the molecules move. Trying to reach EQUILIBRIUM Same amount of particles inside as outside G. Podgorski, Biol. 1010

Two types of diffusion Facilitated Diffusion Simple Diffusion The Plasma Membrane 4/3/2019 Two types of diffusion Facilitated Diffusion Simple Diffusion G. Podgorski, Biol. 1010

Doesn’t require energy The Plasma Membrane 4/3/2019 Simple Diffusion Doesn’t require energy Moves high to low concentration Example: Oxygen diffusing into a cell and carbon dioxide diffusing out. G. Podgorski, Biol. 1010

Facilitated diffusion The Plasma Membrane 4/3/2019 Facilitated diffusion Doesn’t require energy Uses channel proteins to move high to low concentration Examples: Glucose or amino acids moving from blood into a cell. G. Podgorski, Biol. 1010

Membrane Transport Osmosis There is an inverse relationship between the concentration of solute and the amount of water present Water will always move from high to low consentration Descriptions that are used are always relative—to the other side of the membrane

The Plasma Membrane Cell in Hypotonic Solution Less salt outside the cell than inside the cell 4/3/2019 10% NaCL 90% H2O CELL 60% NaCL 40% H2O What is the direction of water movement? G. Podgorski, Biol. 1010

The Plasma Membrane Cell in Hypertonic Solution more salt outside the cell than inside the cell 4/3/2019 20% NaCL 80% H2O ENVIRONMENT CELL 5% NaCL 95% H2O What is the direction of water movement? G. Podgorski, Biol. 1010

No NET MOVEMENT OF H2O (equal amounts entering & leaving) The Plasma Membrane 4/3/2019 Isotonic Solution Hypotonic Solution Hypertonic Solution No NET MOVEMENT OF H2O (equal amounts entering & leaving) Lower solute concentration in the solution Higher solute concentration in the solution G. Podgorski, Biol. 1010

Membrane Transport Active transport (energy required) Solute pumping (sodium-potassium pump) Bulk transport (endo/exocytosis) IMPORTANT FOR RECOVERY FROM NERVE IMPULSE AND BULK TRANSPORT WHEN PHAGOCYTES ENGULF PATHOGENS

Active Transport Requires energy or ATP The Plasma Membrane 4/3/2019 Active Transport Requires energy or ATP Moves materials from Low to High concentration EXAMPLE: Sodium/Potassium pump Pumping Na+ out & K+ in against strong concentration gradients. G. Podgorski, Biol. 1010

The Plasma Membrane Transport Proteins 4/3/2019 Some carrier proteins change shape to move materials across the cell membrane G. Podgorski, Biol. 1010

PHAGOCYTE ENGULFING AND DESTORYING PATHOGEN

Intro to Cell Division Two major phases… Interphase – cell growth and carries out metabolic processes Cell division – cell replicates itself to produce more cells for growth/repair CELL DIVISION IMPORTANT TO KNOW WHEN WE DISCUSS TISSUE REGERNATION – SOME TISSUES (CARDIAC MUSCLE, NERVE, AND SKELETAL MUSCLE) ARE LARGELY AMITOTIC AFTER THEY MATURE ALSO IMPORTANT WHEN WE DISCUSS HOW THE CELL CYCLE CAN B/M OUT OF CONTROL = CANCER

Steps of Cell Division

Steps of Cell Division

Intro to Protein Synthesis Proteins are important! They are major building materials for cells and enzymes are required for chemical reactions Your genes are blueprints for building proteins Information flows in one direction… DNA  RNA  protein PROTEIN SYNTHESIS IS IMPORTATN WHEN WE DISCUSS DISORDERS THAT RESULT FROM AN ABNORMAL PROTEIN THAT IS PRODUCED (AS A RESULT OF GENETIC MUTATION). ALSO – MUSCLE CELLS HAVE TWO NUCLEI WHICH IS HELPFUL FOR THEM SINCE THEY NEED TO PRODUCE MORE PROTEIN THAN OTHER CELLS IN THE BODY transcription translation

Protein Synthesis (Role of RNA) Transfer RNA (tRNA) Transfers appropriate amino acids to the ribosome for building the protein Ribosomal RNA (rRNA) Helps form the ribosomes where proteins are built Messenger RNA (mRNA) Carries the instructions for building a protein from the nucleus to the ribosome

Protein Synthesis (in detail) Transcription Transfer of information from DNA’s base sequence to the complimentary base sequence of mRNA Translation Base sequence of nucleic acid is translated to an amino acid sequence Amino acids are the building blocks of proteins

Intro to Cellular Respiration The process of converting simple sugars to ATP that can be used for energy RESPIRATION FORMULA IMPORTANT WHEN WE GET TO THE RESPIRATORY SYSTEM AND DISCUSS WHY WE ARE LOADING OXYGEN AND UNLOADING CARBON DIOXIDE…POSSIBLY DISCUSS THE BUFFER SYSTEM TOO HERE

Respiration: An Overview The process by which cells break down food sources such as glucose, fats, and protein and release their stored energy. Two main types Anaerobic – no oxygen required Aerobic – requiring oxygen Both forms produce energy storage molecules called ATP – adenosine triphosphate. http://www.chemistry.wustl.edu/~courses/genchem/LabTutorials/Cytochromes/images/flowchart1.jpg

Anaerobic Processes No oxygen is required for these processes. Includes glycolysis, the breakdown of glucose, and fermentation. Some bacteria and yeast are examples of anaerobes. http://www.biol.vt.edu/research/images/C._perfringens_in_mac._jpg.jpg http://www.utoronto.ca/greenblattlab/images/a/yeast%201.jpg

Cellular Physiology Fermentation Use when you are oxygen deficient Less efficient than aerobic respiration by-product is lactic acid that results a burning sensation LACTIC ACID FERMENTATION TAKES PLACE WHEN WE DON’T GET ENOUGH OXYGEN TO OUR MUSCLE CELLS – CAUSES THE BURN AND SOARNESS

Fermentation Pyruvate can be metabolized by: Alcoholic fermentation Lactic acid fermentation AF produces ethyl alcohol and CO2 – yeast can ferment apple juice to fill a balloon. LAF produces lactic acid. It can build up in muscles during strenuous exercise and cause burning and soreness.

Aerobic Processes Requires oxygen. Most organisms are aerobes. Equation for Aerobic respiration: C6H12O6 + 6O2  6CO2 + 6H2O + Energy Based on this equation – Why do we breathe? http://www.oum.ox.ac.uk/thezone/animals/life/images/excrete.gif

The Mitochondria If O2 is present following glycolysis, pyruvate is modified and enters the mitochondria. Here food is broken down completely into CO2. Energy storage molecules like NADH and ATP are produced. This is why the mitochondria is called the power house of the cell.

Oxygen picks up electrons and hydrogen ions to form water. The Role of Oxygen Energy carriers like NADH drop off electrons and as they “fall” to oxygen during metabolism energy is stored in a payload of ATP. Oxygen picks up electrons and hydrogen ions to form water. ATP Energy from electrons O2 H2O

ATP: Adenosine Triphosphate ATP is the cells energy currency. Cellular work such as metabolism, transport, and movement is powered by the breakdown of ATP. ATP Structure Ribose – a 5-carbon sugar Adenine – a N-base 3 phosphate groups

ATP / ADP Cycle ATP is constantly being used and remade in the cell. Energy is released or stored by breaking or making a phosphate bond. http://www.columbia.edu/cu/biology/courses/c2005/purves6/figure06-09.jpg

Cellular Respiration DISCUSS WHERE THESE OCCUR IN THE CELL AND WHICH STEPS NEED OXYGEN