WATER CYCLE

What is the water cycle?

The water cycle is the process by which water is continuously transferred between the surface of the earth and the atmosphere.

https://www.metoffice.gov.uk/weather/learn-about/weather/how-weather-works/water-cycle

How does the water cycle work?

CHECK YOUR KNOWLEDGE:
Water cycle cloze and crossword


INTERACTIVE ACTIVITIES:
CK-12

WATER SCARCITY

MAYBE YOU DO NOT KNOW THAT WE HUMANS HAVE A SEVERE WATER SCARCITY PROBLEM.

WATCHING THIS SERIES OF VIDEOS YOU ARE GOING TO UNDERSTAND WHY.

1. When is water safe to drink?

3. Where we get our fresh water

4. Fresh water scarcity: An introduction to the problem

TO EXPLORE OTHER TOPICS ABOUT WATER EXPLORE THIS LINK:

https://blog.ed.ted.com/2017/08/08/5-ted-ed-lessons-about-water/

What is water?

YOU WILL FIND THE ANSWER TO THIS AND OTHER INTERSTING QUESTIONS CLICKING INTO THIS LINK:

https://www.bbc.co.uk/bitesize/topics/z9r4jxs/articles/zkd3rwx


DO NOT FORGET TO TEST YOUR KNOWLEDGE USING THE ATTACHED QUIZ

What are living things?

Living organisms have certain life processes in common. There are seven things that they need to do to count as being alive. The phrase MRS GREN is one way to remember them:

• Movement - all living things move, even plants
• Respiration - getting energy from food
• Sensitivity - detecting changes in the surroundings
• Growth - all living things grow
• Reproduction - making more living things of the same type
• Excretion - getting rid of waste
• Nutrition - taking in and using food
• There are two types of nutrition
• Heterotrophic nutrition: animals eat other living beings.
• Autotrophic nutrition: plants do not eat other living beings. They obtain their food from water, air and soil.

It can be easy to tell if something is living or not. A teddy bear might look like a bear, but it cannot do any of the seven things it needs to be able to do to count as being alive.

A car can move, it gets energy from petrol (like nutrition and respiration), it might have a car alarm (sensitivity), and it gets rid of waste gases through its exhaust pipe (excretion). But it cannot grow or make baby cars. So a car is not alive.

ORIGINS OF LIFE

In this in this post we're going to learn about the origin of life through a interesting series of videos and other resources.

The first and most relevant question is.... Can Science explain the origin of life?

EDPUZZLE: MYSTERIOUS ORIGINS OF LIFE ON EARTH
https://edpuzzle.com/media/5da0972a973aa641068cc593

Why People Need Plants

The purpose of this lesson is to teach students that plants provide people with food, clothing, shelter, and many other things that we use in our daily lives.




ACTIVITY 1:
List three items you use every day.
Trace each of those items back to a plant by drawing a picture.

ACIVITY 2:
Make a list of things that people get from plants. List and discuss each item.


Compare your list with this one:



Food: vegetables, fruit, meat, eggs, dairy, etc.
Oxygen: plants make this through photosynthesis
Clothing: cotton jeans, flax, and rayon fabric
Medicine: herbal teas, cancer treatment medicines developed from bark of the Yew tree, active ingredient in aspirin was developed from the bark of willow trees, etc.
Paper: from wood pulp
Furniture: lumber from trees
Cosmetics: plant dyes, plant oil fragrances, nut shell exfoliants in facial wash, etc.
Energy sources: biofuel, firewood, etc.
Shelter: lumber from trees and straw bales for homes.

ACTIVITY 3:



Distribute the following plant products to each group.

Cotton fabric
Flower
Fruit
Maple syrup
Granulated sugar packet
Perfumed vegetable soap
Vegetable
Paper
Wooden object

Discuss the origin of each product. Try to fit the using People Need Plantsworksheet, and fill out the appropriate spaces.
After groups are finished, ask one group where they placed each object.Conclusion: Humans depend on plants for survival. Variation: Instead of doing the worksheet in groups, fill it out as a class while the teacher holds up an example of each item on the list.

Air Composition And air pollutants

Unpolluted air Composition

The Earth is surrounded by a mixture of gases called the atmosphere. The main gases in the atmosphere, and their approximate percentages in dry air, are shown below.

Gases in the atmosphere

gas	percentage in dry air
nitrogen	78 per cent
oxygen	21 per cent
argon	1 per cen

The atmosphere also contains a small but important amount of carbon dioxide, approximately 0.04 per cent, and tiny amounts of a few other gases.

Activity. Draw a pie chart showing the relative amounts of the three main gases in the air.

If you need help to do that click here

Humidity

In addition to these, air also contains water vapour. The percentage of water vapour varies from one location to another, and according to weather conditions. This is why the percentages of the other gases are usually quoted for dry air.

Humidity is the amount of water vapor present in the air. Water vapor is the gaseous state of water and is invisible to the human eye.^[1] Humidity indicates the likelihood of precipitation, dew, or fog.

What is relative humidity and how does it affect how I feel outside

Earth's atmosphere composition has changed over time
The Earth’s atmosphere has changed over billions of years, but for the past 200 million years it has been much as it is today.

Story of the atmosphere

The composition of the present day atmosphere is very different from that of the early Earth. Evidence can be interpreted in different ways leading to a number of explanations as to how the atmosphere has changed. 

Volcanoes admit large amount of gas into the atmosphere

The atmosphere of the early Earth was largely made up of carbon dioxide and water vapour, probably coming from volcanoes. When the Earth cooled the water vapour condensed to form the oceans. 

Carbon dioxide dissolved in the oceans and began to form sedimentary rocks. A lot of carbon dioxide was trapped underground and eventually formed fossil fuels. 

Indirect evidence

The early atmosphere cannot be measured directly so scientists look for indirect evidence. This includes the chemical make-up of rocks, examining air bubbles in ice cores and looking at fossils. 

Some fossils suggest early organisms underwent the process of photosynthesis, using the carbon dioxide and releasing oxygen. This meant carbon dioxide levels in the atmosphere went down and oxygen levels went up.