China's Nine-Dashed Map: Maritime Source of Geopolitical ...
The green objects represent ________? Dashed line? Passive or Active transport?
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Transcript of The green objects represent ________? Dashed line? Passive or Active transport?
• The green objects represent ________?
• Dashed line?
• Passive or Active transport?
• Molecules in aqueous solution = solute
• Cell (or plasma) membrane
• Passive transport; Diffusion of solutes toward equilibrium
Osmosis
• Diffusion of water
– Towards equilibrium
– High concentration of water to low concentration of water
Osmoregulation = controlling water balance internally in relation to the outside environment
• Isotonic: (iso = same) cell is in a solution of equal solute concentration• Hypotonic: (hypo = below) cell is in a solution of lower solutes• Hypertonic: (hyper = above) cell is in a solution of higher solutes
• Purple objects represent ___?
• Left side passive or active?
• Right side passive or active transport?
• Transport proteins in plasma membrane
• Passive transport; high concentration to low
• Active transport; against concentration gradient– Expend energy
ATP
Energy?
• Capacity to do work
• Kinetic E– energy in motion– E.g. muscle contractions, heat, light, active
transport
• Potential E– stored energy– E.g. object at rest atop hill, food, ATP
• Energy conversion; transform from one form to another
Laws of E transformation
• 1st Law of thermodynamics– Energy conservation– E can be transferred or transformed– E cannot be created or destroyed
e.g. sunlight to starch via photosynthesis
Laws of E transformation
• 2nd Law of thermodynamics– E escape or transfer during
conversions• e.g. heat released during
muscle contractions is transferred to the environment
• Cells convert potential E to cellular E
– Organized starch or glucose molecules to ATP
– E escape leads to disorder• Entropy
= amount of disorder or chaos in a system
• How to deal with Entropy & prevent total chaos?• Energy input
– More E is required to replace the E that escapes– Plants absorb solar E (kinetic E)– Animals eat food (potential E)– chemical reactions in cells convert energy– http://www.youtube.com/watch?v=5KIhDVLbMeY
Two types of chemical reactions in regards to Energy flow
Endergonic reactions &Exergonic reactions
• Endergonic reaction
– Net input of energy
– Increasing potential E
– Building carborhydrates• making bonds• e.g. plants
photosynthesizing
• Exergonic reaction
– Chemical rxn that releases energy
– Covalent bonds of reactants have more potential E than products
– Breaking down carbohydrates
• Potential E to ATP• Breaking bonds
ATP powers cellular work
• Breaks bond via hydrolysis• Phosphorylation• Exergonic or Endergonic?• e.g. transfer of phosphate to motor protein
causes contraction (muscle cells, flagella movement)
Enzymes• Proteins that change the rate of
chemical reactionsMany act as catalysts – speed up
reactions…. How?
• Lower the activation energy= energy required to initiate a chemical
reaction
– Carbohydrates are potential E to fuel the cells– Cells convert ATP; to power a reaction– Enzymes make it easier for that reaction to
occur
Cyclist resting atop the hill is potential E… he doesn’t start speeding down the hill until the final little push to get him over the last barrier
• Enzymes are catalysts (the push)