Biology 204 Chapter 5-6 Study Guide Quiz 2

Membrane Structure

Solved: The diffusion problem by trapping RNA inside of cell to increase concentration

Created: The osmosis crisis (RNA concentration led to high solute concentration inside of cell → water entered cell and cells lysed

Osmosis

-Movement of water from low to high solute concentration

-Total concentration of molecules that cannot pass membrane affect osmosis equally (Ex: H+, nucleotide, RNA polymer all effect it the same amt)

-Solute concentration matters

Proton Pump

Solved: Osmosis crisis (allowed for active transport of H+)

Created: Energy crisis (needs ATP)

-Ribozyme that pumps H+ ions out of cell (For every RNA added, 1 H+ is removed)

-Allows cell to equalize total solute concentration in and out of the cell

-Active transport → Needs ATP for energy

-DRAW

ATP

-Adenosine triphosphate

-Provides energy by breaking off a phosphate group: ATP → ADP + iP + Energy

-Regenerated with energy: ADP + iP + Energy → ATP

DNA World

DNA → (Transcription) → mRNA → (Translation) → Protein (enzymes)

Phospholipid Bilayer

-Fluid Mosaic Model: Includes phospholipids, embedded proteins, and carbohydrates

Protein Types:

• Channels

• Transporters

• Pumps (H+ pump)

Passive Transport

Movement of molecules from high to low concentration

-No energy required

Simple Diffusion

Passive transport directly through membrane

-High to low concentration

-Small and nonpolar

Facilitated Diffusion

Passive transport through membrane proteins

-High to low concentration

-No ATP needed

-Large (>10 atoms), charged, and/or polar

-Increases rate of diffusion

Ex: Carrier proteins (Glucose carrier) and Channel Proteins (aquaporins)

Active Transport

Movement of molecules from low to high concentration

-Requires the use of energy (ATP)

-Enhances concentration gradient

-Ex: Pumps (Proton Pump, Sodium Potassium Pump)

Pumps (Active Transport)

-Perform active transport (ATP Hydrolysis; breaking off iP to make ADP)

-Occurs because cell needs to create a gradient

Example:

Proton Pump: Removes protons (H+) to combat increased solute concentration from RNA replication. (Benefit of lysis prevention outweighs ATP usage)

Sodium/Potassium Pump: Pumps out 3 Na+ & pumps in 2 K+

Anaerobic Respiration

Solved: Energy Crisis (makes 2 ATP)

Created: Food crisis (needs glucose)

-Metabolic process that uses glucose to make ATP in the absence of oxygen

-Made up of Glycolysis + Fermentation

- Inefficient; production of energy without oxygen (only makes 2 ATP)

DRAW (Glycolysis + Fermentation + H^+ pump)

Metabolism

Chemical reaction in a cell

-Creates energy + materials needed to grow, reproduce, and survive

-Polymerization: Uses energy by hydrolyzing ATP, joining carbons

-Depolymerization: Makes energy in form of ATP, breaking down carbon molecules

Oxidation

-Losing electrons (H+) (Less H+, more O)

Oxidized: losing electrons

Reducing agent: giving another molecule electrons

-Oxidized molecule is the reducing agent

-Transfer of electrons from high to low energy state used to create energy

Redox

-Gaining electrons (H+) + lose Oxygen (More H+, less O)

Reduced: gaining electrons

Oxidizing agent: taking electrons from another molecule

-Electron transfer

-Reduced molecules have reducing power → powers chemical reactions (ex: ADP+iP → ATP)

Cofactors

Electron carriers for metabolism

Ex: NAD+ (reduced to NADH)

Glycolysis

Net Equation: Glucose + NAD+ + 2 ADP → 2 Pyruvate + 2 NADH + 2 ATP

-Depolymerization (6 carbon → 3 carbon) & makes energy

-Investment Phase: 2 ATP + Glucose → 2 G3P

-Crux Reaction: 2 G3P + 2 NAD+ + 2 iP → 1, 3 dPGA + 2 NADH

-Payoff Phase: 3 carbon molecules (don’t need name) + 4 ADP (2 ADP x 2) → 2 Pyruvate + 4 ATP

DRAW

-Solves energy crisis → creates NAD+ issue

Fermentation

Net Equation: Pyruvate + 2 NADH → Lactate/Ethanol + 2 NAD+

-Regenerates NAD+

DRAW

Anaerobic Respiration Overview

Main Point: To produce ATP/Energy → solve energy crisis

Key Components: Glycolysis + Fermentation

Carbon Molecule Input: Glucose

Carbon Molecule Output: Pyruvate

Net ATP: 2 ATP Made

Input carbon oxidized or reduced: Glucose is oxidized (loses H+)

Cofactor: NAD+ → Reduced to NADH in glycolysis & oxidized to NAD+ in fermentation

Chapter 6

Chapter 6

Sulfurogenic Photosynthesis

Net Equation: Sunlight + CO2 + H2S → C6H12O6 + Sulfur

Solved: Food Crisis

Stages:

-Light Dependent Reactions: Sun + H2S + 2 NAD+ → 2H+ + S + H+ + 2NADH

-Light Independent Reactions: Creates Glucose

DRAW

Photosystems

Chlorophyll + electron carrier

Le Chatelier’s Principle

Enough of a product in a solution can lead to the products becoming the reactants, making the reaction go in reverse

-If product of reaction builds up, reaction forced in reverse

Example: Proton pump pumps H+ into the cell and generates ATP rather than pumping H+ out and using ATP

Light Dependent Reactions

1. Sun strikes chlorophyll with energy to break H2S

2. Electrons from H2S go into chlorophyll and transfer to electron carrier

3. Electron carrier reduced 2 NAD+ to 2 NADH using this

4. Electron carrier pumps out a proton (H+)

Solves osmosis crisis like H+ pump

5. H+ pump pumps H+ inside of cell since H+ concentrates outside of cell with electron carrier (H+ pump runs in reverse and also generates ATP)

DRAW

Light Independent Reactions

Use the products of the light dependent reactions to create glucose

Major Parts:

-Reverse Krebs (makes pyruvate from CO2)

-Reverse Glycolysis (makes Glucose from Pyruvate)

Steps:

1. Reverse Krebs: CO2 + ATP + NADH → ADP + Pyruvate + NAD+

2. Reverse Glycolysis: Pyruvate (from reverse krebs) + ATP + NADH → Glucose + NAD+ + ADP

DRAW

Sulfurogenic Photosynthesis Summary

Main Point: Makes glucose (solve food crisis)

Key Components: Light dependent + Light Independent + Reverse H+ pump (makes ATP) + Reverse Krebs (Makes Pyruvate) + Reverse Glycolysis (makes glucose)

Carbon Molecule Input: CO2

Carbon Molecule Output: Glucose (C6H12O6)

ATP Net: Made by reverse H+ pump, Used by light independent reactions

Carbon molecule reduced or oxidized: CO2 is reduced

Cofactor: NAD+ reduced to NADH in light-dependent reactions, oxidized to NAD+ from NADH in light-independent reactions

Sulfurogenic Photosynthesis at Night

Uses anaerobic respiration to produce ATP