1 / 14

Understanding Photosynthesis: Energy Acquisition and the Role of Chlorophyll

This introduction to photosynthesis explores how autotrophs and heterotrophs acquire energy, focusing on the unique role of chlorophyll in plants. Discover how light energy, in the form of electromagnetic radiation and photons, drives the process of photosynthesis. Learn about the characteristics of different pigments, including chlorophyll a and b, and carotenoids, as well as the importance of absorption and action spectra. This guide elucidates the underlying mechanisms of light absorption and energy transformation vital for sustaining life on Earth.

sani
Télécharger la présentation

Understanding Photosynthesis: Energy Acquisition and the Role of Chlorophyll

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Photosynthesis AP Biology Mrs. Hansell

  2. Ways to Acquire Energy • Autotroph- self-feeders- make own food • Plants, some bacteria • Photoautotroph- organisms that use light as a source of energy to make food • Heterotroph- unable to make own food, consume others • Animals

  3. Parts of a Leaf

  4. Chloroplast

  5. The Nature of Sunlight • Form of energy known as electromagnetic energy • Travels in waves • Wavelength- distance between crests in the waves • Electromagneticspectrum- entire range of radiation

  6. Electromagnetic Spectrum

  7. Visible Light • Segment most important to life – detected as various colors by the human eye • Photons- energy particles that make up light • Shorter the wavelength- more energy in photon • Violet light has more energy than red light

  8. Photosynthetic Pigments • Light meets matter- reflected, transmitted, absorbed • Pigment- absorb visible light • Colors we see are wavelengths that are reflected • Plants appear green- reflect green light absorbs violet-blue and red • Spectrophotometer- instrument that measures the ability of a pigment to absorb various wavelengths of light

  9. Spectrophotometer

  10. Photosynthetic Pigments • AbsorptionSpectrum- a graph plotting a pigments light absorption versus wavelength

  11. Absorption Spectra of Chloroplast • Chlorophylla absorbs violet-blue and red light—best for photosynthesis • Blue-Green is reflected—less effective • Actionspectrum- profiles the effectiveness of different wavelengths

  12. Accessory Pigments • Broaden spectrum of colors absorbed • Chlorophyllb- reflects yellow-green • Carotenoids- hydrocarbons various shades of yellow and orange (absorb violet and blue-green light) • Photoprotection- dissipate excessive light energy that could damage chlorophyll or interact with O2

  13. Excitation of Chlorophyll • What happens when chlorophyll and other pigments absorb light? • Molecule absorbs photon of light—electron in molecule excited to orbital with more potential energy • Groundstate- electron in normal orbital • Excitedstate- absorb photon—gain energy

  14. Excitation of Chlorophyll • Ground state to excited state does not last long • Excess energy released as heat when electron goes from excited back to ground state • Makes top of automobiles hot on sunny day—white cars cooler—reflect all visible light • Some pigments emit light and heat as electron falls to ground state--Fluoresce

More Related