8th Biology - Photosynthesis

St. George's College

Subject: BIOLOGY Teacher's notes

Class: Photosynthesis

Objectives

Vocabulary

Date: June 16th

Link and Learn

Prepared by

2009 1

8th Milton A ‐ Transport across the Plant Cell Name

Oral Intervention

Coin

Chocolate

Sergio María Fernanda Alejandra Almendra Anna Paula Sandra E‐C Maia María Belén Alfredo Kinley Arianne Sandra M. Fiorella Rodrigo Giulia Jaime Stefano Bruno

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8th Milton Alpha ‐ Transport across the Plant Cell Name

Oral Intervention

Coin

Chocolate

Marcelo Antonella Paulo Alejandro Brenda Diego Gabriel Valeria Cristina Giuliana Joshua María Gracia Gonzalo N. Paolo Gonzalo R. Giorgio Nicolás María Claudia

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Let's remember previous learned concepts...

Plant Cell 4

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PHOTOSYNTHESIS • Plants need and use the same types of foods (carbohydrates, proteins and fats) as animals but, plants are able to make the food they need from chemicals in the air and the soil.

• Plants do this through Photosynthesis, by which they take carbon dioxide from the air and water from the soil, and use energy from the sunlight to convert them into food, in the form of Glucose.

• Oxygen is also produced in photosynthesis, and although some is used inside the plant for respiration, most is not needed and is given out as a Waste product.

• The sunlight is absorbed by the molecule Chlorophyll (green pigment).

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Reaction Formula Carbon dioxide + Water

6CO2 + H 6 2O

Glucose + Oxygen Sunlight Chlorophyll

6 2 C6H12O6 + O

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Stage 1: Light‐dependent Reaction • A Chloroplast has an outer membrane and an inner membrane.

• Molecules diffuse easily through the outer membrane. The inner membrane is much more selective. Both membranes allow light to pass through.

• The space inside the inner membrane is the stroma, within the stroma the thylakoid membrane is folded and flat, in disc‐like thylakoids.

• These sacs, which contain molecules that absorb light energy for photosynthesis, are arranged in stacks.

• The first stage of photosynthesis begins when light waves hit these stacks.

• There are two substages: Photosystem I and Photosystem II.

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Stage 2: Light‐independent The Dark Reaction • In the final stage of photosynthesis, ATP and NADPH are used to produce energy‐storing sugar molecules from the carbon in carbon dioxide.

• This process is called carbon fixation, the reactions that lead to that are light‐independent reactions, also referred to as dark reactions.

• There are several ways to in which carbon is fixed, the most common is the Calvin Cycle.

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Calvin Cycle Step 1: CARBON FIXATION An enzyme adds a molecule of CO2, to a five‐carbon compound.

Step 2: TRANSFERRING ENERGY Each six‐carbon compound splits into two three‐carbon compounds.

Phosphate groups from ATP and electrons from NADPH are added to the three‐carbon compounds to form higher energy three‐ carbon sugars.

Step 3: MAKING SUGAR One of the resulting three‐carbon sugars leaves the cycle and is used to make organic compounds including: glucose, sucrose, and starch; in which energy is stored for later use by the organism.

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Factors affecting Photosynthesis LIGHT INTENSITY LIGHT INTENSITY: Plants are adapted to different levels of light.

In general, photosynthesis increases as light intensity increases until all of the pigments in a chloroplast are being used.

CARBON DIOXIDE: The concentration of CO2 affects the rate of CARBON DIOXIDE photosynthesis in a way similar to light. Once a certain concentration of CO2 is present, photosynthesis cannot proceed any faster.

TEMPERATURE: Photosynthesis is most efficient in a certain range TEMPERATURE of temperatures. Like all metabolic processes, photosynthesis involves many enzyme‐assisted chemical reactions. Unfavorable temperatures may inactivate certain enzymes so that reactions cannot take place.

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K-W-L Chart What I KNOW about this topic

What I WANT to know about this topic

What I LERANED about this topic

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SURVEY If you want to contribute in improving your Biology class, click in the survey link:

Google Forms Term II ‐ 8th Biology ‐ Class 4

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Resources Used Slide Resource (Group )

Description

Origin

G1 ‐ 2 Image

John Milton

http://bit.ly/QAYb

G1 ‐ 5 Image

Prokaryotic Cell

http://tinyurl.com/o5or6z

G1 ‐ 6 Video

Inner Life of the Cell

YouTube

G1 ‐ 8 Image

Metabolic Pathway

http://bit.ly/fft0D

G1 ‐ 9 Video

Vesicle Formation

YouTube

G1 ‐ 10 Video

Endo‐ and Exocytosis

YouTube

G1 ‐ 11 Images

Lipids Proteins Carbohydrates

http://bit.ly/16WUmF http://bit.ly/191FrS http://bit.ly/HAqG5

G1 ‐ 12 Image

Cellular Inclusions

http://bit.ly/Y1TlJ

G1 ‐ 13 Animation Cell Models

http://bit.ly/Y1TlJ

G1 ‐ 14 Images

Glycogen in Liver Cells Lipids in Liver Cells

http://bit.ly/1HJtPJ http://bit.ly/1HJtPJ

G1 ‐ 15 Image

Types of Polysaccharides Unknown

G1 ‐ 16 Images

Adipose Tissue 1 Adipose Tissue 2

http://bit.ly/1MnU0 http://bit.ly/16DG2F

G1 ‐ 17 Image

Atherosclerosis

http://bit.ly/xw02P

G1 ‐ 17 Video G1 ‐ 17

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Teacher's Notes This class has been designed to cover the topics of Photosynthesis from June 15th till Friday June 19th.

For further knowledge about this topic: 1. Conduct a thorough search under the topic: Photosynthesis on the Web, books and magazines.

2. If findings are not specific, ask your teacher for suggestions.

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Objectives • Learn and understand the intricate process of Photosynthesis.

• Identify and describe the stages in the Photosynthesis process.

• Describe the formula to explain the Photosynthesis process.

Note: All, or most, of the objectives will be covered during class time, however the student must be responsible for those objectives not covered or concluded.

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Vocabulary • • • •

Leaf: Sunlight: Photosynthesis: Phloem:

Note: Most of the vocabulary words will be covered during class time, however the student must be responsible for those words not covered or concluded.

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Link and Learn You can visit the following websites to improve your understanding on the present topic: • • • •

http://science‐learning2009.wikispaces.com http://learningandscience.blogspot.com http://bit.ly/hCg8Z http://bit.ly/15vd0q

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Prepared by

Gerardo LAZARO Science Lead Teacher Email: glazaro@sanjorge.edu.pe Wiki: http://science‐learning2009.wikispaces.com Blog: http://learningandscience.blogspot.com Twitter: http://twitter.com/glazaro

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