Lecture 6 - Cellular respiration Flashcards
Which type of cells do photosynthesis occur in?
Plant cells
Which type of cells do cellular respiration occur in?
Plants and animal cells
What are the four reasons why cells need energy?
- Mechanical work
- Making new materials
- Transport
- Maintaining order
What are two important compartments for respiration?
Matrix and inner membrane
What does this equation represent?
(Glucose + Oxygen –> Carbon dioxide + Water + ATP)
Conversion of chemical energy
T or F
The number of mitochondria is fixed in a cell
False, depends on energy
demand
What is the structure of mitochondria?
- Two membranes (inner and outer)
- Ribosomes
- Cristae
What are the three stages of cellular respiration?
Stage 1 - Glycolsis
Stage 2 - Pyruvate Oxidation & Citric Acid Cycle
Stage 3 - Oxidative Phosphorylation
Where does glycolsis occur?
In the cytosol
What does glycolsis do?
Sugar/glucose (6C) is converted into two pyruvate molecules.
6C -> 2 x 3C
This generates 2ATP and 2 NADH (high energy electrons)
Where does Pyruvate Oxidation & Citric Acid Cycle occur?
In the mitochondria matrix
What do Pyruvate Oxidation & Citric Acid Cycle do?
- 2 pyruvate molecules (2 x 3C) are
converted to 2 Acetyl CoA
molecules. - 2 Acetyl CoA molecules
enter the citric acid cycle - Output are ATP, NADH &
FADH2
Where does Oxidative Phosphorylation occur?
In the inner membrane of the mitochondrion
What are the two parts of Oxidative Phosphorylation?
- Electron transport (electrons from
NADH and FADH2) - Chemiosmosis (ATP production)
How is a proton gradient generated in Oxidative Phosphorylation?
As the electron carriers (NADP and FADH2) move, protons (H+) are pumped across the membrane into the inter-membrane space
Where is ATP synthase found?
Inner mitochondrial membrane
What powers ATP synthase?
The proton gradient across the inner membrane
What does ATP synthase do?
Converts ADP + Pi –> ATP
What does ATP power?
Cellular activity
Cellular respiration can BEST be described as:
(A) using energy released from breaking high-energy covalent bonds in organic molecules to make ATP.
(B) taking electrons from food and giving them to phosphate to make ATP.
(C) taking electrons from food and giving them to oxygen to make water, and using the energy released to make ATP.
(D) converting higher energy organic molecules to lower-energy organic molecules, and using the energy released to make ATP.
(C) taking electrons from food and giving them to oxygen to make water, and using the energy released to make ATP.
Which one of the following statements concerning the mitochondria is INCORRECT?
(A) The number of mitochondria within a cell may change to meet energy demand.
(B) The mitochondrial intermembrane space has a low pH.
(C) Electron transport and chemiosmosis occur within the mitochondrial matrix.
(D) ATP synthase is present on the inner mitochondrial membrane.
(C) Electron transport and chemiosmosis occur within the mitochondrial matrix.
It instead occurs in the inner membrane
Which one of the following statements BEST describes ATP?
(A) The molecule required to activate ATP synthase.
(B) A versatile energy transfer molecule within the cell.
(C) An electron carrier important for oxidative phosphorylation.
(D) The initial substrate in glycolysis.
(B) A versatile energy transfer molecule within the cell.
ATP stores and transfers energy for cellular processes
