Surrounded by a __________ membrane.

Thickened regions called ___________. A stack of thylakoids is called a _________.

_________ is a liquid surrounding the thylakoids.

Chloroplast Structure Review

double

thylakoids

granum

Stroma

Basic Leaf Structure

Why are plants green?

Electromagnetic Spectrum

Light regulates chlorophyll production, so as autumn days grow shorter, less chlorophyll is produced.

The decomposition rate of chlorophyll remains constant, so the green color starts to fade from leaves.

The change of colors

Pigments are light-absorbing compounds.

Pigments appear colored because they absorb light of certain wavelengths and reflect that of others.

Chlorophyll a is the primary pigment in green plants that absorbs red and blue/violet light and reflects green light.

Pigments by definition

Other pigments called accessory pigments are also present in the leaf.Chlorophyll BCarotenoids (orange / red)Xanthophylls (yellow / brown)

Each pigment absorbs a particular wavelength of light in the visible spectrum

These pigments are embedded in the membranes of the chloroplast in groups called photosystems.

Pigments

Structure of Chlorophyll

 A purple plant appears purple because it has high levels of anthocyanins and a fairly neutral pH. 

Red anthocyanins absorb UV light and protect the plants tissues from damage. The undersides of many rainforest floor plants are purple to reflect light absorbed by the top of the leaf…..

What about purple plants?

(because green light absorbs red and blue light) back up to increase absorption by auxillary pigments like carotenoids.

It is a method of separating the components of a mixture.  During the procedure, the mixture will be separated into its individual components, allowing the individual parts to be identified.  

Chromatography is used to separate and identify all sorts of substances in police work. Drugs ranging from narcotics to aspirin can be identified in urine and blood samples, often with the aid of chromatography.

What is paper chromatography?

Paper chromatography is a technique that involves placing a small dot or line of sample solution onto a strip of chromatography paper.

How does it work?

The paper is then placed in a jar containing a shallow layer of solvent. As the solvent rises through the paper, it meets the sample mixture which starts to travel up the paper with the solvent. 

Lab: Are there any other colors besides green in spinach leaves and red in radicchio leaves?

Spinach

Step 1: Write your own hypothesis in an “If… then” format. You should have one hypothesis for spinach and one for radicchio.

Step 2: Follow exact directions on how to collect your data for both samples according to the worksheet.

Step 3: Clean your work station.

Step 4: Be sure to have each portion of your lab report completed thoroughly. Yes.. It is due today.. And be sure to write your own!

Procedure Hints