Chemistry of Life (157 – 163) 6.3 Cell Processes Active and Passive Transport,
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Transcript of Chemistry of Life (157 – 163) 6.3 Cell Processes Active and Passive Transport,
Chemistry of Life (157 – 163)6.3
Cell ProcessesActive and Passive
Transport, Osmosis, Diffusion,
Exocytosis, and Endocytosis
pp. 155 – 156; 195 -2006.2, 8.1Hickox: Baker High School Biology
Objective 2.0: Describe cell processes necessary for achieving homeostasis, including active and passive transport, osmosis, diffusion, exocytosis, and endocytosis• Identifying functions of carbohydrates, lipids, proteins, and nucleic acids in cellular activities• Comparing the reaction of plant and animal cells in isotonic, hypotonic, and hypertonic solutions• Explaining how surface area, cell size, temperature, light, and pH affect cellular activities• Applying the concept of fluid pressure to biological systems
Examples: blood pressure, turgor pressure, bends, strokes
Core concept: Most cell functions involve chemical reactions. Food molecules taken into cells react to provide the chemical constituents needed to synthesize other molecules. There are four main biochemicals: Carbohydrates, Proteins, Lipids and Nucleic acids. Cells use carbohydrates to provide energy. Cells use proteins for cellular construction and repair, cellular chemical activities, and as a back-up energy source if carbohydrates are not available. Both breakdown and synthesis are made possible by a large set of protein catalysts, called enzymes. Cells use lipids for cell membrane construction. Cells use nucleic acids to store genetic information for protein synthesis.
Most cell functions involve chemical reactions. Food molecules taken into cells react to provide the chemical constituents needed to synthesize other molecules. There are four main biochemicals: Carbohydrates, Proteins, Lipids and Nucleic acids. Cells use carbohydrates to provide energy. Cells use proteins for cellular construction and repair, cellular chemical activities, and as a back-up energy source if carbohydrates are not available. Both breakdown and synthesis are made possible by a large set of protein catalysts, called enzymes. Cells use lipids for cell membrane construction. Cells use nucleic acids to store genetic information for protein synthesis.
Vocabulary• Carbohydrate• Nucleic Acid• Lipids• Proteins• Enzyme
Core concep: Cell membranes are selectively permeable. This gives them the ability to maintain cell homeostasis by regulating what enters and leaves the cell. The direction of water movement across the cell membrane depends on the relative concentrations of free water molecules in the cytoplasm and in the fluid outside the cell. Different kinds of cells have evolved different ways of dealing with hypertonic, hypotonic, and isotonic solutions. The cells of plants have rigid cell walls that keep the cells from expanding too much. Animal cells can avoid swelling by moving dissolved particles from the cytoplasm.
Cell membranes are selectively permeable. This gives them the ability to maintain cell homeostasis by regulating what enters and leaves the cell. The direction of water movement across the cell membrane depends on the relative concentrations of free water molecules in the cytoplasm and in the fluid outside the cell. Different kinds of cells have evolved different ways of dealing with hypertonic, hypotonic, and isotonic solutions. The cells of plants have rigid cell walls that keep the cells from expanding too much. Animal cells can avoid swelling by moving dissolved particles from the cytoplasm.
Vocabulary• Passive transport• Active transport• Endocytosis• Isotonic• Exocytosis• Diffusion• Hypotonic• Hypertonic• Homeostasis• Osmosis
Core Concept: Small cells function more efficiently than large cells. Small cells can exchange substances more readily than large cells because small objects have a higher surface-area-to-volume ratio than larger objects. Most cells function best within a narrow range of light, temperature and pH. At very low temperatures, reaction rates are too slow. Extremes of light, temperature and pH can irreversibly change the structure of most protein molecules. Vocabulary: pH, surface area, volume
Turgor pressure is the main pressure of the cell contents against the cell wall in plant cells and bacteria cells, determined by the water content. Blood pressure refers to the force exerted by circulating blood on the walls of blood vessels. High blood pressure can cause stroke.Breathing gas under pressure can present a myriad of possible medical problems. One of these is decompression sickness or "the bends," caused by breathing nitrogen or other gases under pressure, which are not metabolized by the body.
Vocabulary• Bends• Stroke Hickox: Baker High School Biology
Simple to Complex Life’s Levels of Organization
Our journey begins here, atoms like Hydrogen (H) and Oxygen (O)
1. Atoms come together to make up molecules like water, H2O.2. Molecules make up organelles.3. A group of organelles make up cells.
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4. Chemical Reactions
CO2 + H2O C6 H12 O6 + 02
REACTANTS
PRODUCT(S)
CHEMICAL EQUILIBRIUM
Sun
Acids and Bases5. Acids are substances that forms in water and
release hydrogen ions (H+).6. Bases are substances that either take up
hydrogen ions (H+) or release hydroxide ions (OH-).
7. pH measures how acidic or basic a solution is
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pH Scale
7. A pH scale is used to indicate how acid and basic of a solution.8. Ranges from 0-14• 7 = Neutral•>7 = Base•<7 = Acid
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Hickox: Baker High School Biology
pH Matters
pH is a measure of proton (hydrogen ion or
H+) concentration .
In biology, keeping H+ levels within a narrow
range is critically important.
Low pH = lots of H+s, high pH = few H+s.
A strong acid is pH of 2
A strong base is pH of 12
Diffusion
9. Diffusion is the net movement of particles from an area of higher
concentration to an area of lower concentration.
VIDEO FROM FILE
Diffusion continues until there is no concentration gradient!
What affects the speed of Diffusion?10. concentration: main factor, higher the more11. temperature: if temp. increase greater diffusion12. pressure: increasing pressure increases diffusion
no concentration gradient!
Dynamic equilibrium
Dynamic equilibrium
Osmosis
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Osmosis
13. Isotonic Solution - Solute and Solvent (water) concentrations both inside and outside the membrane are equal.
14. Hypotonic Solution - Solution with a lower concentration of solute than the solution on the other side of the membrane.– Cells placed in a hypotonic solution will swell.• Lysis
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Osmosis
15. Hypertonic Solution - Solution with a higher concentration of solute than the solution on the other side of the membrane.– Cells placed in a hypertonic solution will shrink.• Plasmolysis
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The results of diffusion (write into notes)
When a cell is in dynamic equilibrium with its environment, materials move into and out of the cell at equal rates. As a result, there is no net change in concentration inside or outside the cell.
Material moving out of cell equals material moving into cell
16. What type of osmosis is this?(Isotonic, hypotonic, or hypertonic)Does cell shrink, expand, or stay the same?
ISOTONIC
STAYS THESAME
17. What type of osmosis is this?(Isotonic, hypotonic, or hypertonic)Does cell shrink, expand, or stay the same?
HYPOTONIC
EXPANDS
18. What type of osmosis is this?(Isotonic, hypotonic, or hypertonic)Does cell shrink, expand, or stay the same?
HYPERTONIC
SHRINKS
Diffusion in Living Systems: the way cells move substances in and out of the cell
Osmosis is the diffusion of particles through a semi- permeable membrane.
IsotonicHypotonic Hypertonic
Review Quiz:OSMOSIS
20. ___________ is the diffusion of particles through a semi- permeable membrane. 21. __________________: movement of particles across cell membranes by diffusion or osmosis. The cell uses NO energy to move these particles22. ________________: the transport of materials against the gradient and this takes energy23, _________________: the pushing out of water in a plant cell
against the cell wall24. __________________: shrinking of cell due to water moving
out (dissolved solution outside cell high) 25._____________: swelling of a cell due to water moving in
26. ____________: concentrations inside and outside cell is balanced.
VIDEO FROM FILE
OSMOSIS
PASSIVE TRANSPORT
ACTIVE TRANSPORT
TURGOR PRESSURE
HYPERTONIC
HYPOTONIC
ISOTONIC
Biomolecule: Structures vary
amino acids
lipids
Three views of glucose, a common simple sugar.
RINGS
BUNCHED CHAINS
LONG CHAINS
Molecules of Life
Start with water, add lots of small carbon-containing molecules and …….
How do you build a cell?
Use these four major classes of biological molecules:Carbohydrate, lipid, protein, nucleic acid.
CarbohydratesCarbon, Hydrogen, and Oxygen
27. Carbohydrates are used for energy and to create structures.
28. The building blocks for carbohydrates are simple sugars.
Three views of glucose, a common simple sugar.
30. Lipids are large and are made mostly of carbon and hydrogen and small amounts of oxygen.
Fat
Phospholipid
Lipids are used by cells for energy storage, insulation, and protective coatings, such as in membranes.
Phospholipids Form Double-Layered Biological Membranes
Protein p. 66
32. Proteins are the key elements of life.
33. Proteins provide structure for tissue and organs and carry out cell metabolism. Provide the body with the ability to move muscles. They are needed to transport oxygen in the bloodstream.
34. Enzymes, a type of protein that change the speed of chemicals reactions in the body.
34a. An enzyme (p. 66) is a protein that enables other molecules to undergo chemical changes to form new products. Enzymes increase the speed of reactions that would otherwise proceed too slowly.
SubstrateActive site
Strands of the Protein Keratin Create Hair
Nucleotides are Chains of Linked Amino AcidsDNA and RNA
35. The building blocks of proteins are amino acids!
36. There are two kinds of nucleic acids, DNA and RNA. Both are
involved in the storage and flow of information from gene to gene
product.
39. Nucleotides Are the Monomers That Create Polymers of DNA and RNA
The small subunits that make up nucleic acids are nucleotides.
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DNA
Mader: Biology 8th Ed.
RNA