IB BIOLOGY: Cellular Respiration and Gas Exchange QUIZ

Small organisms such as flatworms, protist, bacteria can exchange gases…

with their surroundings through diffusion. Larger organisms have adaptations that reflect their environments.

Why do we need a ventilation system?

Large body size requires a transport system (blood (the medium) which is enabled by the ventilation system) for gases and wastes

What must lungs provide for gas diffusion?

Moist membranes

Ventilation maintains steep O2 and CO2 concentration gradients

• Breathing in raises alveolar O2 allowing Oxygen to enter blood

• Breathing out keeps CO2 levels in alveoli low, facilitating it from blood

True of False is Breathing respiration?

FALSE

What causes Pressure change?

Volume change

What causes volume change?

Rib cage movement, diaphragm, and abdominal muscles

What causes rib cage movement?

External intercostal muscles, and internal intercostal muscles

What happens to the pressure change in INSPIRATION

Decrease in pressure (draws air inwards)

Does volume change in INSPIRATION INCREASE or DECREASE?

Increase

What rib cage movement happens during INSPIRATION?

Goes up and Outward

What happens to external intercostal muscles during INSPIRATION?

Contract

What happens to internal intercostal muscles during INSPIRATION?

They relax

What happens to the diaphragm during INSPIRATION?

It contracts, flattens, moves downward.

What happens to the abdominal muscles during INSPIRATION?

Relax

What happens to pressure change in EXPIRATION?

Increase in pressure (pushes air outwards)

What happens to volume change in EXPIRATION?

Decrease

What happens to rib cage movement in EXPIRATION?

Rib cage moves downward and inward

What happens to external intercoastal muscles during EXPIRATION?

They relax, causing rib cage to lower.

What happens to internal intercostal muscles during EXPIRATION?

They contract

What happens to the diaphragm during EXPIRATION?

Relax

What happens to the abdominal muscles during EXPIRATION?

They contract, pushing diaphragm up.

For efficiency of gas exchange

high concentration gradients must be maintained in the alveoli

When you breath IN…

There is an increase in the concentration gradient of oxygen between the alveoli and blood (diffusing into blood)

When you breathe OUT…

Removes CO2 (and unused O2) increasing the concentration gradient of CO2 between blood and alveoli so CO2 will diffuse out

Alveoli are well adapted to gas exchange…

If the alveoli were not ventilated, equilibrium would be reached and no gas could be exchanged (simple diffusion)

Alveoli INCREASE/DECREASE the surface area for…

INCREASE, gas exchange

Why are the surfaces of alveoli wet?

So gases are dissolved making diffusion easier and preventing the alveoli from collapsing.

Millions of alveoli are connected to a network of capillaries (rich blood supply membrane)

have a high concentration gradient of O2 and CO2

Both of the alveoli and capillaries are…

thin-walled structures that facilitate gas exchange, with a short diffusion path

Type I pneumocytes…

• single layer of cells form the walls of an alveolus

• extremely thin - shorten diffusion distance

• permeable - aids diffusion

Type II pneumocytes…

• secrete fluid to moisten the inner surface of the alveolus

• fluid acids diffusion of gases

• fluid contains surfactant to prevent the walls sticking together - maintains the lumen

• can divide to form Type 1 pneumocytes - repair damage

What is emphysema?

A lung disease, thats not curable but there are treatment that can help you manage the disease
Cause of Inflammation: smoking, chest infections, air pollution

What is Protease?

A lung disease, that is released by leukocytes (white blood cells) and inflamed lung tissue, and protease breaks down connective tissue (elastin) of the lungs

What does Protease result in?

• Deduction of small airways and aveoli

• formations of large air pockets and the breakdown of capillaries

Large air pockets have a much lower…

surface area to volume ratio than alveoli which cause insufficient ventilation. When combined with the reduced blood supply this in turn means inefficient gas exchange and hence low blood oxygen levels.

What are symptoms of Protease?

• Difficulty breathing

• Cough

• Loss of appetite

• Weight loss

How can you determine what stage cancer a person have?

The size of the tumor and how its evolved and spread

What is ATP?

• ATP is the energy currency of the cell

• Contains two high-energy bonds

  • bonds are unstable because the P-groups are negatively charged - easily broken by hydrolysis

What do we use ATP for?

• active transport across the cell membrane

• synthesis of macromolecules by anabolism

• movement of the whole cell by cilia or flagella action

  • movement within the cell of cell compounds such as chromosome movement in mitosis or meiosis

ATP is continually being regenerated from…

ADP and phosphate

Endergonic reaction are…

energy from oxidation of nutrients is stored in high-energy bonds, requires energy to happen

Exergonic reaction…

energy stored in high energy bond is released

The ATP cycle requires/doesn’t require energy to create/break down energy

requires energy to create and release energy

Anabolic reactions…

build up smaller molecules to larger molecules and typically require energy input.

Catabolic reactions…

Breaking down larger molecules to smaller ones

Exergonic reactions…

release energy during the process of breaking down molecules.

Cellular Respiration Equation

C6H12O6 + 6O2 + 6CO2 + 6H2O + ENERGY

During energy transpiration, respiration pathways involve the transfer of… This happens in a series of enzymatically controlled reactions…

energy from complex organic molecules (glucose) into ATP… that can require oxygen (aerobic) or not (anaerobic)

What Redox Reactions

chemical reactions where electrons are transferred from one atom to another involving oxidation and reduction processes.

Oxidation is when…

you lose electrons, increase compounds with C-O bonds

Reduction is when…

you gain electrons, increases compounds with C-H bonds.

The mitochondrial antaomy

Outer membrane, inner membrane, cristae, matrix, Intermembrane spaceand their roles in cellular respiration.

What is the inner membrane of the mitchondria?

A second folded membrane in the middle of the mitchondria

What is the cristae of the mitochondria?

the folds or bends of the inner membrane

what is the matrix of the mitochondria?

Space inside the inner membrane

What is the intermembrane space of the mitochondria?

the space between the two membranes

Why does glycolysis occur?

In the cytoplasm of all cells on the planet

Glycolysis uses?

glucose (6 carbon), 2 ATP, and 2NAD+

Glycolysis produces?

2 pyruvate (3 carbon), 4 ATP, 2 NADH

What is NADH?

an electron receptor molecule, and transports molecules around

glycolysis reactions

• requires 2 ATP for phospholation step making glucose less stable

• glucose is split then reactions produce: pyruvate, 2 ATP, and NADH

• Each step is catalyzed into by different enzyme

• Net gain: 2 ATP and 2 NADH

Electron Shuttles:

• Compounds that store electrons from food

• Exist in both oxidized and reduced forms

• Transfer electrons and protons to other parts of the cell to continue metabolism

Two major kinds of Electron Shuttles:

Oxidated form: NAD+ and FAD

Reduced form: NADH and FADH2

Where do Link Reactions occur?

In matrix of mitochondria.

What does the Link Reaction use?

a pyruvate (3 carbon), 2 NAD+, 2 coenzymes-a

What do Link reactions produce?

2 acetyl-CoA, 2CO2, 2 NADH

Why are Link reactions not lumped with Glycolysis?

Glycolysis occurs in the cytoplasm and link reactions occurs in the mitochondrial matrix

Why don’t ANAEROBIC reactions use this reaction?

They don’t go past glycolysis and instead go through the process of FERMENTATION to recycle NAD+

During Fermentation…

• If a cell stops at glycolysis it runs out of NAD+

• Allows cells to oxidize NADH back to NAD+ in order to continue anaerobic cellular respiration

• Pyruvate is reduced into one of a variety of molecules

What fermentation process is this?

Alcohol fermentation

What fermentation process is this?

Lactic acid fermentation

What’s another name for the Krebs cycle

Citric Acid Cycle

When does the Krebs cycle occur?

In the matrix of the mitochondria, twice per glucose

What does the Krebs cycle use?

A molecule of Actyl-CoA (2 Carbon), 3 NAD+, 1 FAD and 1 ADP

What does the Kreb’s cycle produce?

2CO2, 3 NADH, 1 FADH2, 1 ATP

The Kreb's cycle per glucose: 2 ATP, 4CO2, 6 NADH, 2 FADH2

Single cycle: 2 CO2, 1 ATP, 1 FADH2, 3 NADH + H+

Two cycles: 4 CO2, 2 ATP, 2 FADH2, 6 NADH + H+

What does Glycolysis, link reactions, and the Krebs cycle produce what?

NADH and FADH2

What do carriers (glycolysis, link reactions, krebs cycle) deliver and to where?

High-energy electrons to oxidative phosphorylation

What are the two parts of oxidative phosphorylation?

Electron transport chain and chemiosmosis

What does the double membrane of the mitochondria in oxidative phosphorylation do?

Allows a proton gradient to form

In the electron transport chain how do batteries generate energy?

Completing a circuit by allowing electrons to flow through from negative ends to positive

When electron transport chains create a flow of electrons what does it do?

Generates power to move protons across the inner mitochondrial membrane.

How does the electron transport chain work?

• the reduced electron shuttles (NADH and FADH2) are oxidized at the electron transport chain

  • Complexes of proteins embedded in the cristae

• Electrons flow through the proteins in the chain due to increase of electronegativity of ETC

• Free energy released pumps protons (H+) through ETC proteins from matrix to intermembrane space

ATP synthase is called?

Chemiosmosis

ATP uses hydrogen ions to…

power “rotors” to generate energy to make ATP from ADP

Where does Oxidative phosphorylation occur?

In the inner membrane of the mitochondria during cellular respiration.

What does Oxidative Phosphorylation use?

• O2 (ETC - electron transport chain)

• 10 NADH (ETC)

• 2 FAD2 (ETC)

What does Oxidative Phosphorylation produce?

• H2O (ETC)

• 10 NAD+ (ETC)

• 2 FAD (ETC)

• > 30 ATP (Chemiosmosis)

How come >30 ATP?

ATP synthesis and oxidation of electron carriers are not directly coupled

• ~3 ATP per NADH

• ~2 ATP per FADH2

• MORE ATP than ANAEROBIC cellular respiration

What is the MAX amount of ATP?

38 ATP

How much more effective is aerobic respiration compared to anaerobic respiration (converting sugar to fuel)

19X

How much efficiency does your body have at converting chemical energy in glucose into chemical energy in ATO

40%

How efficient is a car at converting chemical energy in gasoline into mechanical energy?

15%

What is used in Glycolysis and what gets produced from it?

Glucose gets USED, ATP gets PRODUCED

What gets produced from the Krebs Cycle?

Carbon Dioxide and ATP

Oxidative Phosphorylation in the ETC what gets used and what gets produced?

Oxygen USED, Water PRODUCED

Oxidative Phosphorylation in Chemiosmosis what gets produced?

ATP