Variation and classification 7D Variation and classification 7D Variation and classification Variation Classification

7D Variation and classification

How many different types of living things are there on Earth? 7D Variation – What is a species? How many different types of living things are there on Earth? Scientists have identified almost 2 million different types of living things. Many more are yet to be discovered and scientists estimate there could be up to 30 million different types of living things! Each different type of living thing is called a species. Do members of the same species look exactly the same?

A species is a group of living things with similar features. 7D Variation – Similar but different A species is a group of living things with similar features. Members of the same species can breed together to produce fertile offspring. All dogs are members of the same species but they don't all look the same. TEACHER’S NOTES Typical answers… SIMILARITIES: covered with hair, two eyes, a nose, two ears, four limbs, tail, eat meat DIFFERENCES: colour of coat, size, long or short hair, long or short ears, long or short tail, personality

Name 5 ways in which these dogs are similar. 7D Variation – Similar but different TEACHER’S NOTES Typical answers… SIMILARITIES: covered with hair, two eyes, a nose, two ears, four limbs, tail, eat meat DIFFERENCES: colour of coat, size, long or short hair, long or short ears, long or short tail, personality Name 5 ways in which these dogs are similar. Name 5 ways in which these dogs are different.

Differences between members of the same species are called variation. 7D Variation – What is variation? Differences between members of the same species are called variation.

Give 5 examples of variation between humans. 7D Variation – What is variation? Give 5 examples of variation between humans. What do you think causes variation?

This type of variation is passed on in genes from parent to offspring. 7D Variation – Causes of variation Variation is caused by environmental or inherited factors. Which type of variation is described by each definition? A  This type of variation is passed on in genes from parent to offspring. B  This type of variation is influenced by living conditions and surroundings. inherited environmental

Blood group is another example of inherited variation. 7D Variation – Inherited factors Inherited variation is caused by the genes passed on from parent to offspring. In humans, inherited characteristics include the colour of your eyes and hair. Blood group is another example of inherited variation. Your blood group will never change. How many inherited characteristics can you think of?

Environmental variation is caused by differences in 7D Variation – Environmental factors Environmental variation is caused by differences in living conditions and surroundings. Climate and food supply are environmental factors that influence all living things. How might these factors cause variation?

Your country and culture can cause environmental variation. 7D Variation – Environmental factors For humans, environmental factors can influence the way you look, speak and how you do things. Your country and culture can cause environmental variation. A Buddhist monk shaves off all his hair because it is part of his culture. A Sikh grows his hair long because it part of his culture. Name another way in which their environment may have influenced these people.

by environmental factors? 7D Variation – Inherited factors Some inherited characteristics can be affected by environmental factors. Some musicians are born with natural talent for music, but they have to practise to to play really well. Can you think of other inherited characteristics that might be affected by environmental factors?

Decide which characteristics are inherited, environmental or both? 7D Variation – Inherited, environmental or both? Decide which characteristics are inherited, environmental or both? inherited environmental both blood group wears glasses tongue rolling freckles speaks Italian dyed pink hair natural eye colour height Welsh accent

Are plants also affected by environmental conditions? 7D Variation – Variation in plants Are plants also affected by environmental conditions? Sunflowers were grown in a warm environment under different conditions of soil, water and sunlight. Experiment Fertile soil Water Sunlight Results 1 2 3 4

What are the best conditions for growth of the sunflowers? 7D Variation – Variation in plants Experiment Fertile soil Water Sunlight Results 1 2 3 4 What are the best conditions for growth of the sunflowers? How might sunflower growth be affected if grown in a cooler environment? How could you test your prediction?

7D Variation – True or false? 4. Variation caused by environmental factors can be passed from parent to offspring. 3. Variation only occurs in animals. FALSE! Variation occurs in all living things, including plants. 2. Only living things that are members of the same species can breed together to produce fertile offspring. TRUE! Some species can be interbred. A mule is a cross between a horse and a donkey, but it cannot produce fertile offspring. 2. Only living things that are members of the same species can breed together to produce fertile offspring. 4. Variation caused by environmental factors can be passed from parent to offspring. FALSE! Only inherited characteristics are passed from parent to offspring. 3. Variation only occurs in animals. 5. Identical twins are more alike than most but even they are not exactly the same. TRUE! Identical twins inherit the same features but they have different fingerprints. 1. Members of the same species all look exactly the same. 1. Members of the same species all look exactly the same. FALSE! Members of the same species have similar features but do not look exactly the same. 6. The ability to roll your tongue is an inherited characteristic. TRUE! Have you inherited this type of variation? 5. Identical twins are more alike than most but even they are not exactly the same. 6. The ability to roll your tongue is an inherited characteristic. Click on the box to start the quiz

7D Variation and classification

Living things can be grouped based on the 7D Classification – Sorting living things Living things can be grouped based on the similarities and differences between them. For example, all cats are similar to other cats, but very different from caterpillars.

Sorting similar living things into groups is called classification. 7D Classification – Sorting living things Sorting similar living things into groups is called classification. What two groups would you classify these living things into? horse chestnut tree wheat polar bear starfish daisies hamster butterfly

Classification starts by sorting all living things into 7D Classification – Kingdoms Classification starts by sorting all living things into 5 main groups called kingdoms. Living things animals fungi plants Prokaryotes Protoctista Most living things belong to the animal kingdom or the plant kingdom. Can different plants and animals be sorted into groups?

How many legs does it have? Is it covered in feathers? 7D Classification – Classifying animals There are lots of questions you might ask to continue classifying animals into smaller groups. Is it bigger than a dog? Where does it live? How many legs does it have? Is it covered in feathers? Does it have a backbone? TEACHER’S NOTES Does it lay eggs? How does it breathe? What other questions could you ask to classify animals? Which of these questions is the most important when classifying animals?

animals with backbones animals without backbones 7D Classification - Vertebrates and invertebrates The most important question to ask when classifying animals is: Does it have a backbone? So the animal kingdom is divided into 2 groups: animal kingdom animals with backbones animals without backbones elephant bird fish crab worm spider snail

animals with backbones animals without backbones 7D Classification - Vertebrates and invertebrates animal kingdom animals with backbones animals without backbones These two groups of animals are given special names: invertebrates vertebrates Which name describes which group of animals? Which group do humans belong to?

Vertebrates are classified into 5 groups. 7D Classification - Vertebrates Vertebrates are classified into 5 groups. Complete the table of features for each type of vertebrate. mammals birds reptiles amphibians fish body covering how it breathes where it lives how offspring are produced hairy or furry skin soft, moist skin (no scales) lungs mostly on land lay eggs (in water) lungs gills feathers tough skin with scales scales mostly on land on land on land and in water in water most young born alive lay eggs TEACHER’S NOTES Which feature is the most useful for distinguishing mammals?

7D Classification – Naming living things Classification divides each kingdom of living things into smaller and smaller groups. Animal Chordata Mammal Carnivore Canine Canis familiaris Plant Vascular Lilidae Monocotyledon Liliaceae Narcissus pseudonarcissus Kingdom Phylum Class Order Family Genus Species

Scientists give all living things a special name with two parts: 7D Classification – Naming living things Scientists give all living things a special name with two parts: the first part is the Genus name - the second part is species name Kingdom Phylum Class Order Family Genus Species Animal Chordata Mammal Carnivore Canine Canis familiaris Plant Vascular Lilidae Monocotyledon Liliaceae Narcissus pseudonarcissus The scientific name for a domestic dog is Canis familiaris. What is the scientific name for a daffodil?

Living things have different “common” names in different languages. 7D Classification – Why is classification important? Living things have different “common” names in different languages. Carassius auratus scientific name pesce rosso Italian Goldfisch German pez de colores Spanish poisson rouge French goldfish English All living things have the same scientific name in any language. How does scientific classification make it easier for international scientists to talk about living things?

1. Sorting things into groups is called… a) magnification. 7D Classification – Quiz 1. Sorting things into groups is called… a) magnification. b) fabrication. c) classification. 2. The largest type of group of living things is called a… a) kingdom. b) queendom. c) princedom. TEACHER’S NOTES Answers 1c) 2a)

3. The smallest type of group of living things is called a… 7D Classification – Quiz 3. The smallest type of group of living things is called a… a) vertebrate. b) species. c) fungus. 4. Why do scientists classify living things into groups? a) To list living things in alphabetical order. b) To see how living things are related to each other. c) To arrange living things in order of size. TEACHER’S NOTES Answers 3b) 4b)

5. Animals are divided into two main groups called… a) cats and dogs. 7D Classification – Quiz 5. Animals are divided into two main groups called… a) cats and dogs. b) fish and mammals. c) vertebrates and invertebrates. 6. What do vertebrates have in common? a) They all walk backwards. b) They all have a backpack. c) They all have a backbone.   TEACHER’S NOTES Answers 5c) 6c)

7. What is the body covering on reptiles? 7D Classification – Quiz 7. What is the body covering on reptiles? a) Soft, moist skin with no scales. b) Soft, moist skin with scales. c) Tough, hard skin with scales. 8. Dolphins live in water and give birth to live young that feed off their mother's milk. What kind of vertebrate are dolphins? a) Mammals. b) Fish. c) Amphibians.   TEACHER’S NOTES Answers 7c) 8a)

9. The scientific name for a domestic cat is… a) Tiddles. 7D Classification – Quiz 9. The scientific name for a domestic cat is… a) Tiddles. b) Moggius domesticus. c) Felis catus. 10. The first part of the scientific naming system is… a) the Genius. b) the Genus. c) the Genie. TEACHER’S NOTES Answers 9c) 10b)