Lec 13 slide 4

How are electrons used to pump protons across the membrane

Essentially as electrons are transferred from high energy compounds to low energy compounds, ENERGY IS RELEASED.

Electron pumping protons simplified

• Electrons move through a series of proteins (the electron transport chain)

• as they move from high energy to low energy, they RELEASE energy

• That released energy is used by protein complexes to actively pump H+ (protons) across the membrane.

What happens with the energy that was released when electrons were used to pump protons across the membrane

That energy is then used to pump protons AGAINST its gradient.

How are electrons used to pump protons across the membrane and generate ATP in the MITOCHONDRIA

Carbohydrates and oxygen is used to make carbon dioxide and water. NEED OXYGEN TO SURVIIVE

How are electrons used to pump protons across the membrane and generate ATP in the CHLOROPLAST

Carbon dioxide and water is used to make carbohydrates and oxygen.

What happens in the mitochondria though

food is used as a source of energy to create NADH

• make ATP by breaking down food

What is NADH

a high energy compound that donates electrons to the first proton pump complex which releases energy to pump protons.

What happens after energy is released with NADH

This complex then passes the electron to the next pump complex realesing more energy to pump more protons

what happens in the third pump complex with NADH

the electrons would be passed again to it realsing energy again to pump more protons eventually is passed to oxygen as the TERMINAL ELECTRON ACCEPTOR to make water

The proton gradient is used to make _____

ATP

What happens in the chloroplast though

uses light as the energy source to excite an electron in something called a PHOTOSYSTEM

• store energy in glucose

What does the photosystem do in chloroplast

passes this excited electron to a proton pump complex which releases energy to pump protons

What happens with released energy in chloroplast

then passed to a different photosystem and again excited by light

what is the excited electrons in chloroplast used to make

NADH

what is NADH and the ATP generated from proton gradient used for

to fix carbon dioxide into carbohydrate compounds.