Unit 3 science notes

organisms are classified by what?

the way they get their energy

Autotrophs are from where and do what?

from the sun or chemicals that make organic compounds

Heterotrophs are-

animals that must get energy from food

Most autotrophs use the process of ______

photosynthesis

autotrophs use photosynthesis to convert what

light energy from the sun into chemical energy in the form of organic compounds(glucose)

Photosynthesis can be divided into-

light dependant reactions and light independent reactions

Light dependent reactions is where

light energy is converted into chemical energy which temporarily stores ATP and NADPH

what is NADPH?

energy carrying molecule that is more stable than ATP

Light independent reactions is where

organic compounds are formed using Co2 and chemical energy stored in ATP aswell as NADPH

1st stage of photosynthesis

includes light reactions (sunlight)

Chloroplasts

absorb light

chloroplasts are surrounded by a pair of inner membranes called

thylakoids

thylakoids make

glucose

surrounding the thylakoids is a liquid called

stroma

the light from the sun is made up of

visible spectrum

what is a pigment

compound that absorbs some wavelengths and leaves the others to be reflected

Thylakoids pigments are mostly called

chlorophylls

Chlorophyll A

absorbs more red light

Chlorophyll B

absorbs more blue light

when pigments capture light they convert it into

chemical energy such as Atp and Nadph

hundreds of pigments in proteins are called

photosystem

descibe the steps of light reaction-

light makes electron excited

these electrons are taken from the primary electron acceptor to another molecule

the electron go through the electron transport chain

electrons lose energy and enter photosystem I to regain it

brings electrons closest to membrane with Nadp+ with a proton to make NADPH

how are electrons replaced

an enzyme beside photosystem II spilts water molecules into electrons, protons, and oxygen helping to replace electron that left photosystem II

How do you make ATP in light reactions?

when proteins are pushed into the thylakoid do to the movemen tof electrons, inside the thylakoid the protons become concentrated and the ATP synthesis lets the protons escape and with the energy from them ATP is formed