Photosynthesis Unit

• The light-dependent reactions occur in the thylakoid membranes, while the Calvin cycle occurs in the stroma.
• label this diagram.

  A) outer membrane

  B) inner membrane

  C) thylakoid

  D) stroma

  
• The endosymbiotic theory is the idea that the mitochondria and chloroplasts evolved from symbiotic bacteria. What evidence is there of this theory?

  Endosymbiotic theory is supported by evidence such as the presence of DNA in mitochondria and chloroplasts, their ability to replicate independently, and their inner and outer membranes.
• where do the light dependent reactions take place?

  Thylakoid membrane.
• The light dependent reactions occur in the stroma.
• What substances are the reactants in photosynthesis?

  6 carbon dioxide, 12 water and light energy.
• Photosynthesis is an endergonic reaction because it requires energy (light energy) and it builds larger molecules.
• What is the energy source for photosynthesis?

  The sun.
• The light-independent reactions are also known as the Calvin cycle.
• Which pigment is best able to absorb the most light?

  Chlorophyll a
• Why is it necessary to have 6 carbon dioxides entering the chloroplast?

  To ensure there are enough carbons to create one glucose.
• What two places release electrons from chlorophyll by a photons of light?

  photosystem 1 and 2
• Water molecules release electrons at photosystem 2, which also produces O2 and Hydrogen ions.
• label this diagram of the flowering part of a plant.

  A) petal

  B) anther

  C) filament

  D) stamen

  E) stigma

  F) style

  G) ovary

  H) sepal

  I) pistil

  
• Often pollen matures before the stigma becomes sticky to prevent self pollination which would reduce genetic diversity.
• pollen cases containing sperm cells land on the sticky stigma. A pollen tube grows down into the ovary. Each pollen grain joins with one ovule and each seed is genetically different.
• vascular tissue adapted plants to terrestrial life allowing them to grow much bigger and develop leaves.
• Xylem pulls water up to the leaves from the roots through passive transport processes such as transpiration, adhesion and cohesion.
• cohesion is the attraction between molecules of the same type, which holds the molecules together
• adhesion is the attraction between two molecules that are chemically similar (both water and the cellulose of the xylem are non-polar).
• When light hits a material it is absorbed, reflected or transmitted. A pigment absorbs one wavelength of light and reflects all others. The colour it appears is determined by the wavelengths of light it reflects.
• light intensity = how bright it appears / lumens

  colour depends on wavelength
• The visible light spectrum is between 400 and 700 nanometers.
• wave particle duality refers to light being made of particles called photons but acting like a wave.
• a photosystem is a cluster of 200 - 300 pugment molecules embedded in the thylakoid membrane.
• photo-oxidation is the oxidation of a molecule by light (pigment molecules vibrate when they absorb light and pass the energy on the the reaction centre molecule which loses and electron).
• photosystem 1 = P700
• photosystem 2 = P680
• Label the light dependent reaction elements.

  A) photosystem 2

  B) plastiquinone

  C) NADPH

  D) ATP synthase

  E) cytochrome complex

  F) plastocyanin

  G) photosystem 1

  H) ferredoxin

  I) H2O

  J) O2

  K) light

  L) stroma

  M) thylakoid space

  N) thylakoid membrane