KSU BIO 198 EXAM 5 QUESTIONS WITH
COMPLETE SOLUTIONS
, Describe the First and Second Laws of Thermodynamics and explain why they are
important to the cellular energetics. - ANSWER1st - energy cannot be created or
destroyed, only change forms.
• This is important because all living things need a constant energy source (the sun)
2nd - when transforming energy, some is lost as heat (10% between trophic levels)
Define endergonic and exergonic reactions and describe how they are linked in cellular
energetics. - ANSWEREndergonic - requires energy (hydrolysis; splitting molecules)
Exergonic - releases energy (condensation; putting molecules together)
Describe the basic structure of ATP, understand how it stores and releases cellular
energy (i.e. its role as an energy carrier), and the relationship of ATP to exergonic and
endergonic reactions. - ANSWERATP is the energy carrier of cells. It powers cell
actions. short term usable energy
Adenine, ribose (5-carbon sugar) and 3 phosphate groups
ATP loses a phosphate group (exergonic) which creates ADP
ADP gains a phosphate group (endergonic) which created ATP
Describe oxidation and reduction reactions and explain their relationship to endergonic
and exergonic reactions. - ANSWEROxidation - electrons are REMOVED from
substances when breaking molecules (endergonic)
Reduction - electrons are ADDED. molecules are synthesized. (exergonic)
Oxidation and reduction ALWAYS happen together (redox reactions)
Describe the process of diffusion and the factors that influence diffusion rates. -
ANSWERDiffusion - moving from high concentration to low concentration
- small non-polar molecules diffuse best (carbon dioxide, oxygen)
- CAN occur across membranes
Describe selective permeability and how it influences movement of materials across
plasma membranes, including what types of molecules easily pass through the
membrane and what cannot. - ANSWERSelective permeability - allows some things to
pass through, but not all. Membrane is asymmetric (inside and outside are different).
Only non-polar molecules can pass through because the plasma membrane is polar
(their charges are repelled)
Describe facilitated diffusion and active transport, the differences between them, and
when the cell might use each transport type. - ANSWERfacilitated diffusion - materials
COMPLETE SOLUTIONS
, Describe the First and Second Laws of Thermodynamics and explain why they are
important to the cellular energetics. - ANSWER1st - energy cannot be created or
destroyed, only change forms.
• This is important because all living things need a constant energy source (the sun)
2nd - when transforming energy, some is lost as heat (10% between trophic levels)
Define endergonic and exergonic reactions and describe how they are linked in cellular
energetics. - ANSWEREndergonic - requires energy (hydrolysis; splitting molecules)
Exergonic - releases energy (condensation; putting molecules together)
Describe the basic structure of ATP, understand how it stores and releases cellular
energy (i.e. its role as an energy carrier), and the relationship of ATP to exergonic and
endergonic reactions. - ANSWERATP is the energy carrier of cells. It powers cell
actions. short term usable energy
Adenine, ribose (5-carbon sugar) and 3 phosphate groups
ATP loses a phosphate group (exergonic) which creates ADP
ADP gains a phosphate group (endergonic) which created ATP
Describe oxidation and reduction reactions and explain their relationship to endergonic
and exergonic reactions. - ANSWEROxidation - electrons are REMOVED from
substances when breaking molecules (endergonic)
Reduction - electrons are ADDED. molecules are synthesized. (exergonic)
Oxidation and reduction ALWAYS happen together (redox reactions)
Describe the process of diffusion and the factors that influence diffusion rates. -
ANSWERDiffusion - moving from high concentration to low concentration
- small non-polar molecules diffuse best (carbon dioxide, oxygen)
- CAN occur across membranes
Describe selective permeability and how it influences movement of materials across
plasma membranes, including what types of molecules easily pass through the
membrane and what cannot. - ANSWERSelective permeability - allows some things to
pass through, but not all. Membrane is asymmetric (inside and outside are different).
Only non-polar molecules can pass through because the plasma membrane is polar
(their charges are repelled)
Describe facilitated diffusion and active transport, the differences between them, and
when the cell might use each transport type. - ANSWERfacilitated diffusion - materials
