IV LIVING THINGS Earth a living planet. Our planet is a perfect distance from the Sun to be warm. Our planet has enough mass to hold gaseous of atmosphere. Our planet has a magnetic field that protects us from dangerous radiations. We are lucky; life is possible on our planet. A1: In the following video look for ideas that you haven’t read on the previous paragraph. What else do living things need? http://www.youtube.com/watch?v=1zCQ7QM3CZU All of us have an intuitive idea about what is alive and what is inanimate or lifeless, but sometimes we have wrong ideas about what is alive. A2. Watch the following picture and choose which of them represent living things. A3. Now you should think about your reasons to decide what things are alive or inanimate.
Transcript
IV LIVING THINGS Earth a living planet. Our planet is a perfect distance from the Sun to be warm. Our planet has enough mass to hold gaseous of atmosphere. Our planet has a magnetic field that protects us from dangerous radiations. We are lucky; life is possible on our planet. A1: In the following video look for ideas that you haven’t read on the previous paragraph. What else do living things need? http://www.youtube.com/watch?v=1zCQ7QM3CZU All of us have an intuitive idea about what is alive and what is inanimate or lifeless, but sometimes we have wrong ideas about what is alive. A2. Watch the following picture and choose which of them represent living things.
A3. Now you should think about your reasons to decide what things are alive or inanimate.
A4: Which processes enable living things to …
• Create new living things • Adapt to their environment • Obtain the energy they need
A5: The coal that we use in a barbecue is made of carbon. Do you think coal is a living thing? A6: Out of the following substances, which are living things?
o Flower o Meat o Worm o Cow o Cloud o Leaf of a plant o Kidney
LIVING THINGS It is not easy to establish boundaries between life and nonlife, scientists are still arguing about these ideas, but there exists an agreement on three concepts based on what living things do:
• Nutrition: refers to all the processes, which enable living things to obtain energy, and matter they need to live.
• Interaction with the environment: Animals and plants are affected by their
environment. Living things depend upon their environment for their survival.
• Reproduction: refers to all the processes that enable living things to create new living things.
All living things have a similar composition; about 95% of living things are made of “O” oxygen, “C” carbon, “H” hydrogen.
Remember: A living being is made mostly of water and organic substances (made of “C” carbon, “O” oxygen and “H” hydrogen). A living being is able to do the three following functions:
• Nutrition • Interaction with the environment • Reproduction.
Every living thing is produced from another living think A7: Perhaps you have seen a dead animal in the countryside and you have probably seen maggots on its body. Where did the maggots come from? In the XVII century many scientists thought that some organisms appear by spontaneous generation. They thought that living organisms could arise spontaneously from nonliving matter. Francesco Redi (1626 – 1698) tried to test this idea with the experiment below: A8: Why do you think about flies, maggots and eggs appear in the first jar and don’t appear in the other two?
In spite of this fact, after some time, when you remove the lid from the jar the meat smells bad and it is putrefy because of microorganism. Unfortunately, Redi’s experiment did not convince everyone. Some argued that while spontaneous generation might not apply to larger organisms like maggots and flies, it might still be applicable to smaller microbes. Louis Pasteur finally answered the question definitively in the late 1800s, in his now classic experiment. Pasteur boiled the sample to kill any existing organisms, days later he removed the lid from the jar and checked for growth of any organism. Pasteur didn’t use meat he used as sample broth. http://www.pasteurbrewing.com/The-Life-and-Work-of-Louis-Pasteur/experiments/Redi-Louis-Pasteur-and-Spontaneous-Generation-for-Kids.html A9: Do you think it would be possible for a living organism to arise from nonliving things?
Some ideas to help you!! Nutrition Autotroph: focused on plants?
• How do the plants make their own food? • Photosynthesis. Sun's energy.
Chemical reaction. Heterotrophs: focused on animals. • Carnivores • Herbivores
• Omnivores
Food energy chain
Interaction with environment Animals and plants are adapted to the habitat • Cactus plants live in dry habitats. Their leaves are sharp spines • What is hibernation? • We notice the weather is getting colder in winter and we put on warmer clothes.
But how do animals and plants survive this changes
In this case, is the man adapted to the environment?
Reproduction Sexual reproduction Asexual reproduction Some organisms like bacteria reproduce using binary fission. They split in two, so one bacterium becomes two bacteria. This always leads to daughter cells, and the offspring will be identical to the parent.
