W11 L2 - Cellular Energy Generation

Flashcards to help learn about cellular energy generation

What is the primary focus of the first lecture in the series of six?

Cellular energy generation

What is the role of ATP?

A major molecule that's a carrier of cellular energy.

Name two key organelles discussed in the lecture where energy generation occurs.

Chloroplasts and mitochondria

What chapter of the textbook is recommended for reading after this lecture?

Chapter 14

Besides Chapter 14, which other chapters are good to read?

Chapters 3 and 13

What is required to maintain living cells?

Repair and generation of order at every level.

What raw materials do cells use to extract energy?

Cells extract energy from the environment when we eat food.

From what source do cells obtain energy?

Oxidation of organic molecules from food

What process do plants use to create their food (sugars)?

Photosynthesis

What is the name of the process by which food molecules are gradually broken down to produce energy?

Cellular respiration

Name two complementary processes that were mentioned.

Cellular respiration and photosynthesis.

What term describes all the chemical reactions that occur in a cell?

Metabolism

What type of pathway describes the process of energy being released by breaking down chemical bonds?

Catabolic pathways

What type of process uses available energy for the synthesis of new molecules?

Anabolism

What type of molecule catalyzes steps in metabolic processes?

Enzymes

What do cells use as unique storing molecules for energy?

Energy carriers

Which molecule is considered the major carrier of energy in the cell?

ATP (adenosine triphosphate)

Besides ATP what other molecules are considered to be Energy carriers?

NADH, NADPH, and FADH2

Where is the energy stored in an ATP molecule?

In the bond between the second and third phosphate groups

What are the three components of an ATP molecule?

A nitrogenous base (adenine), a sugar, and three phosphate groups

What is the precursor to ATP?

ADP (adenosine diphosphate)

Where do we get the input of energy for the generation of ATP?

Food (oxidative phosphorylation) or sunlight (photosynthesis)

Besides ATP, how do other carriers carry energy?

High-energy electrons

How many high energy electrons do NADH and NADPH carry?

Two high-energy electrons plus a proton

What is it called when we transfer of two high energy electrons plus a proton onto NADP?

NADPH being reduced.

When energy carrying molecules release energy to another protein or enzyme what happens?

It becomes oxidized and whatever it's giving it to becomes reduced.

What is oxidative phosphorylation?

the process in generation of ATP from food

High energy electrons drive what?

Proton pumps, which drive the transfer of protons from the side of one membrane to another so you get a proton gradient

What do both animals and plant cells do?

Drive proton pumps to transfer protons

What do plants use to perform photosynthesis?

chloroplasts

Where do high energy electrons come from?

NAD

Where do the protons come from in the production of ATP?

Water

Where do the electrons for the proton pump come from?

NADH

What enzyme allows the movement of protons back to the other side of the membrane?

ATP synthase

What are the two locations where ATP is generated in animal cells and in plant cells?

Mitochondria in animal cells and chloroplasts in plant cells.

What is the process called that couples chemical bond forming reactions with proton pump transport?

Chemiosmotic coupling

What did early eukaryotic cells engulf?

aerobic bacterium or photosynthetic bacterium

What is the main reason that these bacteria were engulfed?

they allowed aerobic respiration

What feature do mitochondria and chloroplasts share with their bacterial ancestors?

They contain their own DNA and the machinery to replicate ribosomes.

What three components do mitochondria contain?

an inner and outer membrane and an intermembrane space

What third set of membranes do chloroplasts contain?

thylakoid membranes

Which cells are mitochondria typically found in?

eukaryotic

What are the two membranes that enclose the mitochondria?

Outer membrane and inner membrane

What protein allows things to move in and out of the outer membrane?

porin

What are the folds in the inner membrane of the mitochondria called?

Cristae

What are the three main components of the mitochondria?

outer membrane, inner membrane space, matrix

What cycle occurs in the mitochondrial matrix?

Citric acid cycle (TCA cycle, Krebs cycle)

What do we refer to the mitochondria as?

Powerhouses of the cell

What two sources generate ATP in non-synthetic cells?

glucose and fatty acids

How many ATP molecules can be generated from the aerobic degradation of one glucose module?

32

List the three steps for cellular respiration.

Glycolysis, TCA or Krebs cycle, and oxidative phosphorylation

Which phase only makes two ATP molecules?

Glycolysis

Which part of the cell does glycolysis take place?

cytosol

How many molecules of ATP are invested at the start of glycolysis?

Two

Is oxygen required for Glycolysis?

No

What molecules transfer a phosphate to ADP from an organic molecule?

Substrate level phosphorylation

What is pyruvate concerted into in the mitochondrial matrix?

acetyl CoA

How many molecules of NADH does the citric acid cycle produce?

3

Where does oxidative phosphorylation take place?

inner mitochondrial membrane

What does the electron bearing carrier receive electrons from?

NADH from the citric acid cycle

What is being pumped from one side (matrix) to another into the intermembrane space?

Proton ions

During oxidative phosphorylation, energy is released from which molecule?

NADH

What happens to NADH during oxidative phosphorylation?

It is oxidized to NAD

How is energy harnessed during oxidative phosphorylation?

Through energy conversion processes in the mitochondrial membrane

Which compound becomes reduced in oxidative phosphorylation?

The compound that gains the electrons.

Oxidative phosphorylation generates how much ATP?

Majority

How many proteins are involved in oxidative phosphorylation?

over 40

Name 3 complexes that make up the enzymes that help push electrons through and pump protons into the intramembranous space.

NADH Dehydrogenase, Cytochrome C Reductase, Cytochrome C Oxidase

Which two mobile carriers move electrons between complexes?

Ubiquinone and Cytochrome C

What does the electron transport chain generate besides a PH gradient?

An electro membrane potential

Electrochemical gradient across the inter mitochondrial membrane includes pressure from what two aspects?

membrane potential and pH gradient

What generates the proton motive force and pulls the protons back?

membrane potential and pH gradient

What are the three terms should be learned?

metabolism, analyzer and catalysis

What three pumps were shown?

3 proton pumps.

What does protein motive force consist of?

Due to the membrane potential and also due to the pH gradient.

Where can we make NADH?

glycolysis and citric acid cycle