6.4 Leaves 1HVTTO

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 1

6.4 Leaves: the green machine

• Jacket in your locker
• Put your things on your desk

       Laptop/Book

       Notebook, pencil case

• Bag on the floor
  
• Read pages 158-162

Lessongoals

• Remember: I can list the ingredients needed for photosynthesis and the products that result from it
  
• Understand: I can explain how photosynthesis works by using the terms sunlight, water, carbon dioxide, glucose and oxygen correctly.
  
• Apply: I can use the structure of a leaf to explain how it supports photosynthesis and limits water loss.
  
• Analyse: I can analyse the effect of limiting factors on the rate of photosynthesis by giving examples of different environmental conditions.

Homework 6.3

Wheel of homework

Go to Lessonup.app and use this code

Reward

Penalty

Rewards

• +1 cm2 cheatsheet = you get to make a cheatsheet for a test. This starts being 1 by 1 cm. Everytime you earn this it gets 1 cm bigger to a max of 4 by 4 cm.
• 1/3 +0.5 = If you earn this 3 times you get to add 0,5 to one of your biology marks.
• Snitch = You can pick a classmate who also is checked for homework, you earn two V's (having 3 earns you a 1/3 +0,5)
• Too bad = You only get one V
  

penalties

• 45 min extra worktime = you need to come after school and do homework, this will last for 45 min or until the task is done
• Coloringpage = You get to pick a coloringpage, You need to color it and perform tasks that might be on it. You need to hand it in during the next lesson, If you don't you get 2 marks.
• 2/1 marks = a mark is an X, if you get 3 of these you will automaticly earn the 45 min extra worktime.
• Snitch = You can pick a classmate who also is checked for homework
• Lucky! = You don't get a penalty

Scan the chapter

Use your book and laptop/notebook

• Go to chapter 6.4 on pages 158-162
• Quickly scan the text for difficult/unknown words
• Make a list of all the words you don't know/understand, add these to your PIF
• Add descriptions and/or synonyms of these words during the lesson

Ami forgot to water his plant, but the stems are still sturdy.
If he is quick, the plant won't die.
What type of stem do the plants have?
Explain how you can tell?

What part of a root mainly takes up water?

1. All parts
2. Tap root
3. secondary root
4. Root hair

Think-Pair-Share

• Think: Work on the assignment on your own.
• The image shows a table with lot's of different foods.
• All food items on the tabel are only possible because of plants
• Describe for at least 4 different food items, how plants are needed for this food.

• Pair: Discuss and compare with your neighbour, improve your answer
• Share: Talk about given answers during plenary session.

Photosynthesis

water + carbon dioxide + sunlight -> glucose + oxygen

H₂O + CO₂ + sunlight -> C₆H₁₂O₆ + O₂

oxygen

carbon dioxide

sunlight

Plants absorb water using their roots. 

This is then tranported via the stems to green parts (mainly the leaves) of the plant where photosynthesis can happen

Carbon dioxide is a gas in the air. 

Plants can 'inhale' this into their bodies, allowing them to use it for photosynthesis

When the sun shines, plants can use the energy in it to perform photosynthesis

Oxygen is also created during photosynthesis. 

The plant releases this into the air, filling it with oxygen

The 3 words in front of the arrow are the ingredients needed for photosynthesis.

The 2 words after the arrow are the result of photosynthesis.

The arrow is important, it shows that a chemical reaction is taking place.

In science, many substances have an abbreviation. 

It's easier to use these than writing the word:

H2O = water

CO2 = carbon dioxide

C6H12O6 = glucose (but you don't need to remember this one

O2 = oxygen

glucose

Glucose (a type of sugar) is created during photosynthesis. 

It is an energy rich substance that the plant uses as its food

Photosynthesis happens in the chloroplasts of plant cells.

These chloroplasts contain chlorophyll, giving them their typical green colour.

Chlorophyll is needed to perform photosynthesis

What happens with the glucose made during photosynthesis?

Parts of a leaf

blade

lateral vein

leaf stalk

main vein

A leaf up close

a stoma is made up of 2 guard cells, which can open and close the stoma.

Water can also 'escape' through stomata!

Plants will therefore close them, to prevent losing too mucht water

Top side of the leaf.

most of the sunlight caught by a leaf is on this side.

A waxy toplayer prevents water from escaping the leaf.

These cells will contain chloroplasts, most of the photosynthesis happening in the leaf will happen in these cells

Leaves contain lots of veins, these veins tranport in 2 directions:

• Water to the cells in the leaf
• Glucose to the other parts of the plant

Bottom side of the leaf.

Will usually catch much less sunlight.

contains many stomata: allowing gasses (like CO2 and O2) to go in and out of the leaves.

Both images are shown as if watching from this direction.

As if you cut trough the black line and look at he edge that is created

Microscopic photo and drawing of cross section of a leaf

Limiting factors and optimum

Photosynthesis needs: water, sunlight, carbon dioxide, suitable temperature.

If one of these is missing, or in short supply it will limit        the amount of photosynthesis happening > it becomes a limiting factor.

Not all plants need the same amounts of these 'ingredients'.

The perfect amount of these ingredients for a plant is its optimum

to limit (something) = to hold back the process/to make the process less productive

Example:

The optimum temperature for most plants is about 25 °C.

If its too cold, plants can't grow well. 

If its too hot, plants have difficulty getting enough water.

In these 2 cases temperature becomes a limiting factor 

These words I'll add to my PIF

What you should do: 6.4

• Pages  158-162 TB
• Asgmt  32, 34, 35, 38-43, 45 pgs. 166-173 WB

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zs = Working in Silence

• No asking questions
• Silent, don't disturb anyone
  
• Stay at your  desk

What you should do: 6.4

• Pages 158-162 TB
• Asgmt 32, 34, 35, 38-43, 45 pgs. 166-173 WB

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zw = Working with whispering

• Teacher is available for questions
• Only whisper with the student next to you
• Stay at your  desk

Someone puts a leaf (still connected to a living plant) under water.
He makes sure that lots of sunlight can hit the leaf.
After a while little airbubbles have formed on the leaf.

Explain: What substance is in these bubbles and on which side of the leaf will they be?

Tidy Duty

3 people each lesson

• Desks: empty and straight
• Chairs:  underneath the desks OR end of day: on the desks
• Floor: no rubbish