Living Things. Observing and recording. Complete the table. Use these words. carnivore mammal legs eyes fur mouth ears nose lynx

Transcription

1 Living Things 5 6 Observing and recording Complete the table. Use these words. carnivore mammal legs eyes fur mouth ears nose lynx name: vertebrate: skin co vering: sense organs: movement: eating habits: Canadian lynx

2 Reporting Discuss the reading. Where can you find lynx in America? What do the y eat? Why are these animals in danger of extinction? Think and discuss. Would the extinction of the lynx be a serious problem? Why? Do you know an ybody who works to protect nature? What do they do? What is your favorite animal? Why do you like it? The Lynx One of the most endangered animals is the lynx. This terrestrial mammal has four legs and a tail. Its fur is brown with black spots. Lynx are predators. These carnivores eat animals, such as sheep, birds and rabbits. Some of the animals they eat are useful for humans. As a result, lynx cause problems for humans. However, people use lynx fur for clothing. The lynx population in the United States is small. There are three principal causes: starvation, poaching and road deaths. First, the lynx habitat is smaller now, so finding food is more difficult. Without food, they starve. Second, people hunt lynx for their fur. Third, many lynx die in traffic accidents. There are lynx populations in Canada and Alaska, and they have been reintroduced to the state of Colorado, where they were extinct. These cats usually live in cold habitats, for example, mountain areas. The World Wildlife Organization is trying to protect the lynx. Learn about the unit Plants, animals, fungi, algae and bacteria are living things. They are all made up of cells. They are bor n, grow, reproduce and die. These processes differentiate them from nonliving things, such as rocks or wind. In this unit, we are going to learn about living things: What are the y like? What are the y made of? What types are there? Key Skills Expressing facts: there are three principal causes; they grow Defining: the process that enables ; substances that plants use Describing abilities: living things carry out life processes; sensitivity enables plants to respond 5

3 What Living Things Are Like. Principal characteristics In nature there are nonliving things and living things. Rocks, air and wind are nonliving things. People, animals and plants are living things. We can recognize living things because the y share the following characteristics: They are born. All living things come from other living things. They eat. All living things need food. The type of food ma y vary. They grow. All living things increase in size during their lifetime. Sometimes the y change in appearance. They react. Living things can perceive what is going on around them, and they react to what they perceive. They reproduce. Living things can create offspring similar to themselves. They die. At some time, all living things stop functioning and cease to live. Living things and nonliving things. Plants are living things. Rocks are nonliving things.. Life processes All living things depend on life processes to sta y alive. W e are going to focus on three basic processes: Nutrition Sensitivity Reproduction. Nutrition Nutrition is the process b y which living things ingest food substances, transform them for their utilization and eliminate waste. Food contains essential nutrients. These are substances that living things use to grow. Nutrients give living things the energ y to car ry out life processes. Nutrition. This process begins with eating. The rest of the process takes place inside the body. nonliving: not alive, lifeless Vocabulary 6

4 . Sensitivity Sensitivity is the process that enables living things to perceive what is happening around them. Sensitivity enables living things to respond to what the y perceive. Thanks to this function, all living things can find food and escape from danger. Humans, like all animals, use their sense organs to perceive what is happening around them. Then the y react: the y move, talk, etc. Sensitivity. When plants detect warmer weather, they bloom. This is an example of reaction or sensitivity. 5. Reproduction Reproduction is the process that enables living things to create offspring similar to themselves. Many animals, including humans, need a mate to reproduce. Ne w living things replace the ones that die. Summary There are living things and nonliving things in nature. Living things carry out life processes: nutrition, sensitivity and reproduction. Reproduction enables life to continue from generation to generation. Ostrich chicks are born. A C T I V I T I E S What six characteristics do all living things ha How many nonliving things can you name? ve in common? Living things Complete the following sentences: Reproduction, Nutrition or Sensitivity. a. involves ingesting food substances. b. enables living things to perceive what is happening around them. c. enables living things to create offspring. Define each life process with a dra wing or photograph. 7

5 The Internal Organization of Living Things. What is a cell? Living things are made up of a large number of very small units called cells. A cell is the smallest living unit that makes up a living thing. Most cells are ver y small, so we need a microscope to see them. A microscope is an instr ument that magnifies the images of small objects. It is lik e a magnifying glass, but much more pow erful. The number of cells in a living thing varies. Some living things are made up of a single cell. They are called unicellular: they can only be seen with a microscope. Other living things are made up of man y cells: the y are called multicellular. Plant cells seen under a microscope. These cells are magnified 500 times.. What are cells like? Cells are living things. This means that, like other living things, they carry out the life processes of nutrition, reproduction and sensitivity. Not all cells are alik e. Cells differ in shape, in size, and in the tasks the y carry out. For example, skin cells are different from bone cells. People use microscopes to study small things. membrane. Parts of a cell Cells ha ve three main par ts: cytoplasm nucleus Plant cell The membrane is a co vering that sur rounds the cell, and separates it from the exterior. The nucleus is the par t that controls the function of the cell. Cytoplasm is the space betw een the nucleus and the membrane. Plant cells also ha ve a hard cell wall around the membrane. This is wh y some plant stems are very hard. Animal cell nucleus cytoplasm membrane wall The parts of animal and plant cells 8

6 . How living things are organized Multicellular living things are ver y organized. In fact, levels of organization exist: Cells group together to for m tissues. Tissues are made up of similar cells that car ry out a common function. F or example, muscle tissue is made up of man y muscle cells grouped together. Tissues for m organs. Organs are made up of a group of tissues that wor k together to car ry out a common function. F or example, muscles and bones are organs. Organs for m systems. Systems are made up of a group of organs that wor k together to car ry out a common function. F or example, the skeletal system is made up of bones. When all the systems wor k together, they form an organism. An organism is a complete living thing. For a living thing to be health y, all the systems in an organism must wor k together. LEVELS cell tissue organ system muscle cell muscle tissue muscle muscle system Summary All living things are made up of cells. Cells group together to form tissues. Tissues form organs. Organs form systems. An organism is a complete living thing. Organism horse A C T I V I T I E S Levels of organization in living things. What is a cell? What life processes do cells car ry out? Order these le vels of organization from = the simplest, to 5 = the most complex. tissue organism cell organ system Describe a multicellular living thing. Star t like this: These organisms are made up of cells. Cells form tissues. 9

7 How Living Things Are Classified. Kingdoms of living things Living things are classified into large groups called kingdoms. All living things that belong to the same kingdom share some common characteristics. In other words, living things from one kingdom are different from the living things in other s. There are five kingdoms. These three are the principal ones: The animal kingdom The plant kingdom The fungi kingdom PRINCIPAL KINGDOMS Plant Animal Fungi The principal kingdoms of living things. The animal kingdom Animals share these characteristics: Animals are multicellular. They eat other living things. They can mo ve from one place to another. They have a ner vous system and sense organs. The y can react quickly to stimuli. Humans belong to the animal kingdom. Animals can move. Flock of geese. The plant kingdom Plants share these characteristics: Plants are multicellular. They use sunlight and substances from the soil and air to mak e their own food. They are anchored to the ground. Plants have no sense organs or ner vous systems, but they can react to some stimuli. For example, many plants grow toward the light. Chlorophyll is a substance. Plants use it to make their own food. Chlorophyll makes plants green. 0

8 . The fungi kingdom Fungi can be unicellular or multicellular. The cells in multicellular fungi for m long, slender threads called hyphae. Fungi are usually found underground, on pieces of wood or on decomposing food. Some fungi produce a stem, also called a fr uiting body. This is the reproductive par t of the fungus. Mold is also a fungus. It grows on bread, but it does not produce a large, reproductive par t like the mushroom. Some common characteristics of fungi are: They do not mak e their own food. The y depend on other organisms for food. They are attached to something. They cannot mo ve by themselves. 5. Other kingdoms Many living things belong to other kingdoms. Algae live in the w ater and mak e their own food lik e plants. Man y algae are for med by a single cell, but others are multicellular and can be as big as a tree. Bacteria are unicellular, and can live in different environments: w ater, soil, air or inside other living things. Some can only be seen with a microscope. The y are microorganisms. The y often feed on deca ying matter, such as dead animals or plants. 5 Summary Living things are grouped into kingdoms. There are three principal kingdoms: animal, plant and fungi. 5 mushroom hyphae Parts of a fungus. Most of a fungus is underground. The part above ground is the mushroom, the reproductive part. Bacteria (in red) on the head of a pin. Bacteria are very small living things. A C T I V I T I E S Can you name one characteristic of each kingdom: animal, plant and fungi? What kingdom do these living things belong to?: a. They depend on other organisms for food; the y are attached to the ground. b. They are made up of man y cells and can mak e their own food. c. They can mo ve and eat other living things. How are plants and algae similar? How are the y different? Which living things feed on fallen lea ves or dead animals?

9 A C T I V I T I E S UNDERSTAND. Identify the life processes: reproduction, sensitivity, nutrition. FIGURE IT OUT 5. Classify these living things: animal, plant or fungi. a. enables mushrooms to obtain nutrients and grow. b. enables birds to travel to w armer places in winter. c. enables poppies to produce other poppies. A C B D. Match the columns and write sentences. A tissue similar cells An organism a group of similar tissues A system a group of similar organs An organ various systems Example: A tissue is made up of E F. Read and write yes or no in each box. feed on dead plants or animals can make their own food can move Animals Plants Fungi APPLY 6. Match each photo with a life process: are born, move, react, eat, reproduce. A B Draw a living thing from each kingdom. C D. Label the parts of a plant cell. a. b. E d. c. Describe each process. Example: a. Living things.

10 I CAN DO IT How to Observe and Describe a Fungus Procedure To describe a living thing, first obser ve it carefully. Then talk about its size, color and shape. For example, to describe a mushroom, answer these questions:. What size is it? Measure the height of the mushroom and the width of the cap.. What color is the cap?. What shape is the cap? Flat, convex or conca ve.. What color are the gills? 5. What color is the stem? 6. What shape is the stem? Is it cylindrical or does the thickness change? 7. Does the stem have rings? Description of larger mushroom on the left. SIZE Height 0 to 0 centimeter s Width 5 to 5 centimeter s width CAP Flat: Concave: Convex: STEM Color Shape Lamellae (gills) Color Red with white spots Concave White White height ring cap gills Shape Ring Wider at the bottom Yes Amanita mushrooms Do it yourself gills Choose a mushroom and describe it. Use the photos or a real fungus: First, answer the questions. Then complete a char t like the one abo ve. Oyster mushrooms. Size: diameter -9 cm, height 5-8 cm. Blue foot mushrooms. Size: diameter 5-5 cm, height 8-0 cm.

11 Now I Know Check what you know. Complete the word map. Living things carry out life processes that include sensitivity are made up of that form that form are grouped into that include the plant kingdom that form systems. Copy and complete the sentences. Use words from the word map. Living things carry out that include, and. are made up of that form, that form. things are grouped into that include.. Answer the questions. What are three basic life processes? What are cells? What are the main par ts of a plant cell? What is an organism?. Complete the word map. Draw pictures, too. Principal kingdoms of living things are Animal kingdom for example: for example: for example:

12 Find out and write A Report on a Living Thing. Find information. Choose a plant, animal or fungus. Find information: use the Inter net, etc.. Select and organize information. Put your infor mation in order. Include these sections: a. Title. The name of the living thing b. Appearance. What is it lik e? Describe the size, shape and color. Number the par ts. c. Habitat. Where does it live? Indicate the area (USA, Latin America, ). Type of place (forest, river, coast, ). d. Type of food. How does it live? Is it food for living things? e. Usefulness for humans. Do humans use this living thing? How? f. Interesting facts. Curious or unusual infor mation you ha ve found.. Write and illustrate the report. Write two or three sentences for sections b, c, d, e and f. Include a photograph or dra wing.. Review your report carefully. Have you included all the sections? Ha ve you answ ered the questions? Check the spelling, too. Citizenship Microbes Can Be Helpful or Harmful Some microbes are helpful, but others are harmful. Microbes help us make yogurt, cheese and bread. They give a unique texture and taste to the food. Other microbes are harmful: they can make you sick. Diseases like measles and mumps are caused by microbes. Microbes cause foods to decay. If you eat moldy bread, you can have stomach problems. Microbes also cause tooth decay. How can you be safe from harmful microbes? Do you do these things? Wash your hands. Avoid contact with sick people. Clean your teeth. Store food carefully. Cheese. Milk is fermented with special types of bacteria to make cheese. 5