biology: photosynthesis Flashcards
Energy storage molecule
ATP adenosine triphosphate
Three phosphates+adenine+ribose
Energy released when it loses a phosphate and becomes ADP (adenosine diphosphate) and an inorganic phosphate
Why do we need energy?
Cell growth, metabolism, reproduction, movement
Stomata
Microscopic pores in leaf
CO2 and O2 are exchanged
H2O can also leave
Chloroplasts
Organelles located in plant cells
Surrounded by two membranes
absorbs sunlight for photosynthesis
How to build up ATP?
Adenosine diphosphate+ phosphate + energy= ATP
How do organisms get energy to form ATP?
Autotrophs make their own
Heterotrophs eat other organisms
How do autotrophs make heir own food?
Through photosynthesis
Photo= using light
Synthesis= making food
Light+6H2O+6CO2=C6H12O6+6O2
WHat parts of chloroplast involved with photosynthesis?
Thylakoids, granum, stroma, pigments
Thylakoids
Photosynthetic membrane
Granum
Stack of thylakoids
Stroma
Fluid outside of thylakoids
Pigments
Light absorbing molecules
Embedded in thylakoids membrane
Absorbs every light color except the one we see
Chlorophylls a and b
Pigment that absorbs all light wavelengths except green
Located in leaves and non-woody stems
Carotenoids
Pigment that absorbs all light except orange and yellow
What three types of tissues are plants made of?
Dermal, vascular, ground
Why type of structure does vascular tissue make?
Xylem and phloem
What structure does dermal tissue make?
Outer layer of plant
What type of structure does ground tissue make?
Photosynthetic tissue
Function if xylem
Carries water, minerals and hormones
Function of phloem
Carries sugar/food
What two reactions are involved in photosynthesis
light dependent and light independent
light-dependent reaction
using sun’s energy and H2O to make chemical energy (ATP and NADPH)
NADPH: carries electrons through photosynthesis
light-independent reaction
aka Calvin Cycle
uses ATP/ NADPH from light dependent reaction and CO2 to make sugar
photosystem
cluster of chlorophyll and carotenoids
photosystem II and I
both embedded in thylakoid membrane
what occurs in both photosystem II and I
- light is absorbed directly by pigments
increases the electron energy level - “excited”; electrons passes to Electron Transport Chain
embedded in thylakoid membrane
Where do the electrons end up?
Electrons+NADP+ =NADPH
NADPH goes to Calvin Cycle
How do electrons get replaced in Photosystem II
from Photosystem II electrons
replaced by splitting H2O into H+, O2, an electron
O2 is oxygen we breath
how do electrons get replaced in photosystem I
electrons from Photosystem II (ETC)
Where does the Calvin cycle occur?
Stroma
What happens to the protons?
H+ (protons) constantly pumped into thylakoid space from water splitting
Creates H+ gradient so thylakoid space is more positively charged
H+ travels down concentration gradient through ATP synthase to get outside thylakoid space and into stroma
generates ATP
ATP travels to Calvin Cycle
this process is called chemiosmosis
What does the Calvin cycle make and from what?
Makes sugar from CO2
What things effect photosynthesis?
Light, water, temperature
