CARBON CYCLE

SCOOBY DOO & THE GANG are wondering what is the carbon cycle?

 

The Carbon Cycle

All living things are made of carbon. Carbon is also a part of the ocean, air, and even rocks. Because the Earth is a dynamic place, carbon does not stay still. It is on the move!
In the atmosphere, carbon is attached to some oxygen in a gas called carbon dioxide.
Plants use carbon dioxide and sunlight to make their own food and grow. The carbon becomes part of the plant. Plants that die and are buried may turn into fossil fuels made of carbon like coal and oil over millions of years. When humans burn fossil fuels, most of the carbon quickly enters the atmosphere as carbon dioxide.
Carbon dioxide is a greenhouse gas and traps heat in the atmosphere. Without it and other greenhouse gases, Earth would be a frozen world. But humans have burned so much fuel that there is about 30% more carbon dioxide in the air today than there was about 150 years ago, and Earth is becoming a warmer place. In fact, ice cores show us that there is now more carbon dioxide in the atmosphere than there has been in the last 420,000 years.



CARBON CYCLE - VIDEO

CARBON CYCLE ACTIVITY #2

CARBON CYCLE - ACTIVITY

NITROGEN CYCLE

WHAT IS THE NITROGEN CYCLE?

AIR -  What is it? 

• Air consist of about 78% of nitrogen, 
• 21% out of oxygen, 
• less than 0,1% out of carbon dioxide, 
• with an avarage of 1% of water vapour. 

The Nitrogen Cycle

The nitrogen cycle describes how nitrogen moves between plants, animals, bacteria, the atmosphere (the air), and soil in the ground. Nitrogen is an important element to all life on Earth. 

Different Nitrogen States 

For Nitrogen to be used by different life forms on Earth, it must change into different states. Nitrogen in the atmosphere, or air, is N₂. Other important states of nitrogen include Nitrates (N0₃), Nitrites (NO₂), and Ammonium (NH₄). 

Nitrogen Cycle 

This picture shows the flow of the nitrogen cycle. The most important part of the cycle is bacteria. Bacteria help the nitrogen change between states so it can be used. When nitrogen is absorbed by the soil, different bacteria help it to change states so it can be absorbed by plants. Animals then get their nitrogen from the plants. 

Diagram of the nitrogen cycle

Processes in the Nitrogen Cycle

• Fixation - Fixation is the first step in the process of making nitrogen usable by plants. Here bacteria change nitrogen into ammonium.
• Nitrification - this is the process by which ammonium gets changed into nitrates by bacteria. Nitrates are what the plants can then absorb.
• Assimilation - This is how plants get nitrogen. They absorb nitrates from the soil into their roots. Then the nitrogen gets used in amino acids, nucleic acids, and chlorophyll.
• Ammonification - This is part of the decaying process. When a plant or animal dies, decomposers like fungi and bacteria turn the nitrogen back in ammonium so it can reenter the nitrogen cycle.
• Denitrification - Extra nitrogen in the soil gets put back out into the air. There are special bacteria that perform this task as well.

Why is nitrogen important to life? 

Plants and animals could not live without nitrogen. It is an important part of many cells and processes such as amino acids, proteins, and even our DNA. It is also needed to make chlorophyll in plants, which plants use in photosynthesis to make their food and energy. 

How have humans altered the nitrogen cycle? 

Unfortunately, human activity has altered the cycle. We do this by adding nitrogen into the soil with fertilizer as well as other activities that put more nitrous oxide gas into the atmosphere. This adds in more nitrogen than is needed by normal cycle and upsets the cycle's balance. 

Fun Facts

• Around 78% of the atmosphere is nitrogen. However, this is mostly not usable by animals and plants.
• Nitrogen is used in fertilizer to help plants grow faster.
• Nitrous oxide is a greenhouse gas. Too much of it can also cause acid rain.
• Nitrogen has no color, odor, or taste.
• It is used in many explosives.
• About 3% of your body weight is nitrogen.

http://www.ducksters.com/science/ecosystems/nitrogen_cycle.php

NITROGEN CYCLE #1

NITROGEN CYCLE #2

WATER CYCLE

Scooby & the Gang are in the library doing research on the WATER CYCLE.  
Let's see what they have learned.

First off, study the diagram of the WATER CYCLE/HYDROLOGIC CYCLE.  Read the facts below.  Add all blue Vocabulary Terms on 3 x 5 cards.  Click on the highlighted links below.



The Water Cycle (also known as the hydrologic cycle) is the journey water takes as it circulates from the land to the sky and back again.

The Sun's heat provides energy to evaporate water from the Earth's surface (oceans, lakes, etc.). 
Plants also lose water to the air (this is called transpiration). The water vapor eventually condenses, forming tiny droplets in clouds. When the clouds meet cool air over land, precipitation (rain, sleet, or snow) is triggered, and water returns to the land (or sea). 
Some of the precipitation soaks into the ground. Some of the underground water is trapped between rock or clay layers; this is called groundwater. But most of the water flows downhill as runoff (above ground or underground), eventually returning to the seas as slightly salty water. 

WATER CYCLE VIDEO
 
REVIEW:
 The Water Cycle
Water on Earth is always changing. Its repeating changes make a cycle. As water goes through its cycle, it can be a solid (ice), a liquid (water), or a gas (water vapor). Ice can change to become water or water vapor. Water can change to become ice or water vapor. Water vapor can change to become ice or water.

How do these changes happen? Adding or subtracting heat makes the cycle work. If heat is added to ice, it melts. If heat is added to water, it evaporates. Evaporation turns liquid water into a gas called water vapor.
If heat is taken away from water vapor, it condenses. Condensation turns water vapor into a liquid. If heat is taken away from liquid water, it freezes to become ice.
The water cycle is called the hydrologic cycle. In the hydrologic cycle, water from oceans, lakes, swamps, rivers, plants, and even you, can turn into water vapor. Water vapor condenses into millions of tiny droplets that form clouds. Clouds lose their water as rain or snow, which is called precipitation. Precipitation is either absorbed into the ground or runs off into rivers. Water that was absorbed into the ground is taken up by plants. Plants lose water from their surfaces as vapor back into the atmosphere. Water that runs off into rivers flows into ponds, lakes, or oceans where it evaporates back into the atmosphere.
The cycle continues. 

Did You Know?

• A fixed amount of water recirculates around the Earth.
• Water moves in certain directions from place-to-place (reservoir-to-reservoir) by only certain processes and pathways.
• Some processes of transfer are rapid while others are much slower.
• A conceptual "reservoir" of water is not quite the same thing as a reservoir in which water is stored.
• When land-based glacial ice melts and runs off into the sea, sea level rises.
• When land-based glacial ice forms, sea level drops.
• When floating icebergs melt into the sea, sea level doesn't change.
• Glacial ice is made up of freshwater that had previously fallen as snow.
• Evaporation of seawater requires an input of energy; condensation of clouds releases energy.

VOCABULARY TERMS

Accumulation - the process in which water pools in large bodies (like oceans, seas and lakes).

Condensation - the process in which water vapor (a gas) in the air turns into liquid water. Condensing water forms clouds in the sky. Water drops that form on the outside of a glass of icy water are condensed water. 

Evaporation - the process in which liquid water becomes water vapor (a gas). Water vaporizes from the surfaces of oceans and lakes, from the surface of the land, and from melts in snow fields.

Precipitation - the process in which water (in the form of rain, snow, sleet, or hail) falls from clouds in the sky.

Subsurface Runoff - rain, snow melt, or other water that flows in underground streams, drains, or sewers.

Surface Runoff - rain, snow melt, or other water that flows in surface streams, rivers, or canals.

Transpiration - the process in which some water within plants evaporates into the atmosphere. Water is first absorbed by the plant's roots, then later exits by evaporating through pores in the plant.

WATER CYCLE - STUDY JAMS

WATER CYCLE - ACTIVITY  #1

WATER CYCLE - ACTIVITY #2 

WATER CYCLE - ACTIVITY #3

WATER CYCLE - QUIZ 

Controlling Plant Growth - QUIZ

Take the Quiz:    

• Draw the diagram below on notebook paper.

• No talking to a friend.  

• Turn into the box drawer when you have finished the quiz.

  1.)

  What is this picture showing?

2.)  LABEL THE DIFFERENT TROPISMS REPRESENTED BY THE PLANT.  DRAW AN ARROW POINTING TO THE TROPISM & LABEL, ALSO ADD IF THE TROPISM IS NEGATIVE OR POSITIVE TROPISM.







 

PLANTS AS MEDICINE

PLANTS: TROPISMS & HORMONES

Welcome to Tropism & Plant Hormones. 

• Click on the highlighted links for videos presenting Tropisms.  
• Read the facts below. 
• Review the slides show at the bottom of the blog. 
• Add the pink colored terms & definitions on your 3 x5 cards.
• Due:  12/11
• Quiz:  12/13

 Watch the following videos - click on the highlighted links

 TROPISM  #1

TROPISM #2

'tropism' is a growth in response to a stimulus. 

Plants grow towards sources of water and light, which they need to survive and grow.
Auxin is a plant hormone produced in the stem tips and roots, which controls the direction of growth. 

• Plant hormones are chemicals that regulate plant growth

• Plant hormones are used in weedkillers, rooting powder and to control fruit ripening.

Tropisms -The direction of plant growth

Plants need light and water for photosynthesis. They have developed responses called tropisms to help make sure they grow towards sources of light and water.

There are different types of tropisms:

• Tropism – growth in response to a stimulus
• Positive tropism – towards the stimulus
• Negative tropism – away from the stimulus
• Phototropism – growth in response to the direction of light
• Geotropism – growth in response to the direction of gravity
• Thigmotropism - the directional bending or turning response of a plant upon contact with a solid surface or object; it is basically a sense of touch in plants. For example, the tendrils of vines are thigmotropic.

VOCABULARY GAME  (CLICK LINK)

Controlling the direction of growth

Auxin is a plant hormone responsible for controlling the direction of growth of root tips and stem tips in response to different stimuli including light and gravity.

• Auxin is made at the tips of stems and roots. It's moved in solution to older parts of the stem and root where it changes the elasticity of the cells. More elastic cells absorb more water and grow longer, causing bending in the stem or root. It's thought that light and gravity can interfere with the transport of auxin causing it to be unevenly distributed.

Auxin experiment

3 groups of seeds are grown in a cardboard box.
A - when the tips are removed, no auxin is made so the stems do not grow
B – when the tips are covered, auxin moves to all parts of the stem causing all parts to grow
C - when the tips are lit from one side only auxin accumulates on the shaded side causing it to grow more than the illuminated side

Uses of plant hormones

Weedkillers

Selective weedkillers kill some plants but not others. This can be useful for getting rid of dandelions in a lawn without killing the grass, or getting rid of thistles in a field without killing the wheat plants. The selective weedkiller contains growth hormone that causes the weeds to grow too quickly. The weedkiller is absorbed in larger quantities by the weeds than the beneficial plants.

Rooting powder - Rooting powder makes stem cuttings quickly develop roots. Rooting powder contains growth hormones.

Controlling fruit ripening

Some hormones slow the ripening of fruits and others speed it up. These hormones and their inhibitors are useful for delaying ripening during transport or when fruit is displayed in shops.

Dormancy

Dormancy stops seeds germinating until conditions are ideal for growth. Hormones can be used to remove the dormancy of a seed so it can germinate at all times of year. Buds and flowers can also be naturally dormant. Hormones can also be used to make plants grow bushier, make them flower or control the growth of hedge plants.

PLANT UNIT - REVIEW ACTIVITIES

REVIEW FOR PLANT UNIT TEST
Carefully review all PLANT notes, vocabulary terms, & the following activities!!!

TEST - FRIDAY, 12/6

SOIL

 

LEAVES

 

FLOWERS

 

SEEDS

 

TREES