BIOL 1201 Study Guide - Quiz Guide: Exergonic Reaction, Cellular Respiration, Kinetic Energy
Energy Flow in Cells 9/18/2015 5:26:00 PM
What is energy?
The capacity to do work
Kinetic energy that is stored as potential energy in cells phones and other
devices.
o Kinetic energy=energy of movement=½(mv)^2
▪ Light
▪ Heat
▪ Electricity
o Potential energy=stored battery
▪ Chemical energy
Batteries
▪ Positional
Laws of thermodynamics
1st law: Conservation of Energy: amount of energy in a system remains
constant
2nd Law: when converted from one form to another, useful energy decreases
o Entropy (a measure of disorder) increases
o Low entropy to high entropy
▪ Low disorder to high disorder
Energy flow on Earth
Energy input from the sun
o Photoautotrophs (plants, other producers)
o Heterotrophs (consumers, decomposers)
The suns energy output is mainly heat
Energy flow in chemical reactions
Chemical reactions: the making and breaking of chemical bonds.
Reactants: starting materials (substrates)
Products: results of the reaction
Exergonic reactions: releases energy
A+B (high energy)→C+D (low energy)
o Energy is released some as heat and others into useful
energy.
o During cellular respiration glucose (CH2OH) and O2
decomposes and creates H2O and CO2 (respiration)
Endergonic reactions: give off energy
find more resources at oneclass.com
find more resources at oneclass.com
o C+D (Low energy)→A+B (high energy)
o Water and CO2→ glucose and O2 (photosynthesis)
Exergonic Reactions
o A Burning glucose (sugar): an exergonic reaction
How is cellular energy carried between coupled reactions?
Phosphorylation-adding a phosphate
ATP is charged 3 phosphates--high energy content
ADP uncharged 2 phosphates—low energy content
o
Phosphorylation & Synthesis
Synthesis of ATP: readily available energy
Breakdown of ATP: Releasing Energy for work
Coupled reactions within living cells
Glucose -- exergonic (glucose breakdown)-- →CO2 +H2O+Heat
ATP synthesis (endergonic)
ADP breakdown (exergonic)
ATP is broken down to ADP
And then used during protein synthesis to form protein from amino acids
GTP—Guanine Tri Phosphate
Electron Carriers
Reaction that gives off energy creates higher charged electrons
These electrons can have different types of charges
Nucleotides can accept electron forming NADH
How do Cells control their Metabolic Reactions
Metabolism: sum of all the chemical reactions in cells
o Exergonic + Endergonic= Metabolism
Metabolic Pathway: series of reaction linked in a sequence
o Metabolic Pathways
▪ Initial substrates—Pathway 1
▪ …Check through the Power Points again. Look at the
images from this chapter.
How is metabolism controlled?
Enzymes regulate chemical reactions
Cells couple reactions
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Kinetic energy that is stored as potential energy in cells phones and other devices: kinetic energy=energy of movement= (mv)^2, light, heat, electricity, potential energy=stored battery, chemical energy. 1st law: conservation of energy: amount of energy in a system remains constant. 2nd law: when converted from one form to another, useful energy decreases: entropy (a measure of disorder) increases, low entropy to high entropy, low disorder to high disorder. Energy input from the sun: photoautotrophs (plants, other producers, heterotrophs (consumers, decomposers) Chemical reactions: the making and breaking of chemical bonds. A+b (high energy) c+d (low energy: energy is released some as heat and others into useful energy, during cellular respiration glucose (ch2oh) and o2 decomposes and creates h2o and co2 (respiration) Endergonic reactions: give off energy: c+d (low energy) a+b (high energy, water and co2 glucose and o2 (photosynthesis) Exergonic reactions: a burning glucose (sugar): an exergonic reaction. And then used during protein synthesis to form protein from amino acids.
