Chapter 8 Flashcards
What is ATP and what does it stand for?
- Adenosine Triphosphate
- Compound that cells use to store and release energy.
- Is used by all types of cells as basic source of energy.
- Consists of
- Adenine (Base), Ribose (a 5-carbon sugar), & 3 phosphate
groups.
What is ADP and what does it stand for?
- Adenosine Diphosphate
- Stores energy
- Has 2 phosphate groups unlike ATP which has 3.
- If a cell has remaining energy, it stores a small amount of the energy by adding a phosphate group to ADP.
How does energy stored in ATP release?
- By breaking down the chemical bond between 2nd and 3rd phosphates.
- ATP releases and stores energy by breaking and reforming the bonds between its phosphate groups.
What is the energy in ATP used for?
- Cellular activities
- Active transport
- Protein synthesis
- Muscle contraction
Why is ATP not good for long term energy storage?
- ATP is not good at storing energy for long
- Most cells only have a small amount of ATP
- Cells regenerate ATP from ADP as needed by using the energy in food.
What is the equation for Photosynthesis?
6CO^2 + 6H^2O + light –> C^6H^12O^6 + 6O^2
How does light work?
- Energy travels to Earth in the form of light
- Different wavelengths of light are looked at as different colors
- Objects absorb every wavelength but one
- Black/Dark colored objects absorb all wavelengths of light equally
- White/Light colored objects reflect all wavelengths of like equally.
What is a Chloroplast?
Organelle in which photosynthesis occurs.
What are photopigments?
- Helps photosynthetic organisms capture energy from sunlight (light absorbing molecules)
- Chlorophyll: Main pigment in plants
- Plant pigments include: Chlorophyll a & b (absorb most colors well except green (reflects green), carotenoids (absorb light in other regions of the spectrum reflecting oranges, reds, yellows.
What happens when a chlorophyll molecule gets excited?
Energy is transferred to electrons in pigments (chlorophyll) when they absorb sunlight.
Where does photosynthesis occur?
In chloroplast
Endosymbiotic theory
Chloroplasts are structurally similar to and likely evolved from photosynthetic bacteria.
Where do plants get their green color from
From chlorophyll, the green pigment within chloroplasts.
Where does CO2 and O2 enter and leave the leaf
Stomata
Leaf anatomy/structure
Cuticle, upper epidermis, Palisade mesophyll, Vascular bundle (xylem and phloem), spongy mesophyll, lower epidermis, stoma, guard cells.
Where are chloroplasts found in the highest concentration?
The mesophyll, one cell has 30-40 chloroplasts
Thylakoid
Where light reactions occur
Thylakoid membrane
Barrier that surrounds the thylakoid; pigments such as chlorophyll are found here
Granum
A stack of thylakoids
Stroma
- Region outside the thylakoid membrane
- Where the Calvin Cycle occurs
- Cytoplasm of Chlorplasts
Oxidation
Becomes more positive when an electron is lost
Reduction
Becomes more negative when an electron is gained
NADP+
Electron and hydrogen ion (H+) acceptor molecule. (Carries the high-energy electrons from the thylakoid membrane to the stroma).
NADPH
Electron holder molecule (Holds the molecule)
What is the light reaction formula?
Light + H^2O + NADP+ + ADP –> O^2 + NADPH + ATP
What does the thylakoid of the chloroplast transform light energy into?
The chemical energy of ATP and NADPH
Chemiosmosis
The process of using proton movement (H+) to join ADP and P
ATP Synthase
An enzyme embedded in the thylakoid membrane
Photophosphorylation
The process of creating ATP using a protein gradient created by the energy gathered from sunlight
Calvin Cycle formula
CO^2 + NADPH + ATP –> C^6H^12O^6 + NADP+ + ADP
What is needed to start the Calvin Cycle
High energy electrons (e-)
Carbon Fixation
Converts CO2 into a different organic form to be used in reaction.
RuBisCo
An enzyme that catalyzes the reaction.
What factors affect photosynthesis?
Water supply, amount of sunlight, temperature, carbon dioxide.
