Photosynthesis (Module 1.4.2)

Photosynthesis (Module 1.4.2)

use light to manufacture their own food. “self-feeders using light”

photoautotrophs

“other feeders” Other organisms, such as animals, fungi, and most other bacteria must rely on the sugars produced by photosynthetic organisms for their energy need.

heterotrophs

group of bacteria synthesize sugars, not by using sunlight’s energy, but by extracting energy from inorganic chemical compounds.

chemoautotrophs

is a multi-step process that requires sunlight, carbon dioxide (which is low in energy), and water as substrates. it releases oxygen and produces glyceraldehyde-3-phosphate (GA3P), simple carbohydrate molecules (which are high in energy) that can subsequently be converted into glucose, sucrose, or any of dozens of other sugar molecules.

Photosynthesis

process of photosynthesis occurs in a middle layer.

mesophyll

The gas exchange of carbon dioxide and oxygen occurs through small, regulated openings. also play roles in the regulation of gas exchange and water balance

stomata

In all autotrophic eukaryotes, photosynthesis takes place inside an organelle.

chloroplast

For plants, chloroplastcontaining cells exist in the:

mesophyll.

Within the chloroplast are stacked, disc-shaped structures called:

thylakoids

a stack of thylakoids is called a:

granum

the liquid-filled space surrounding the granum/

stroma

energy from sunlight is absorbed by chlorophyll and that energy is converted into stored chemical energy.

light-dependent reactions

the chemical energy harvested during the light-dependent reactions drive the assembly of sugar molecules from carbon dioxide. they require the products of the light-dependent reactions to function.

light-independent reactions

longer the wavelength = less energy is carried

EnergyShort, tight waves = carry the most energy

can only “see” (absorb) 700 nm to 400 nm light.

plant/retinal pigments

function as photosynthetic pigments that are very efficient molecules for the disposal of excess energy

carotenoids

The overall function is to convert solar energy into chemical energy in the form of NADPH and ATP.

light-dependent reactions

which passes energy from sunlight to the reaction center; it consists of multiple antenna proteins that contain a mixture of 300–400 chlorophyll a and b molecules as well as other pigments like carotenoids.

lightharvesting complex

In plants, carbon dioxide (CO2) enters the leaves through stomata, where it diffuses over short distances through intercellular spaces until it reaches the mesophyll cells. Once in the mesophyll cells, CO2 diffuses into the stroma of the chloroplast—the site of light-independent reactions of photosynthesis.

Calvin cycle

The light-independent reactions of the Calvin cycle can be organized into three basic stages:

fixation, reduction, and regeneration

the first step in the breakdown of glucose to extract energy for cellular metabolism. The process does not use oxygen and is therefore anaerobic.

Glycolysis

cytoplasm of both prokaryotic and eukaryotic cells. begins with the six carbon ring-shaped structure of a single glucose molecule and ends with two molecules of a three-carbon sugar called pyruvate.

Glycolysis

Processes that use an organic molecule to regenerate NAD+ from NADH are collectively referred to as

fermentation