NS4: PLANTS AND ANIMALS

 

UNIT 4: Plants and animals

4.1.- Plant classification

Ø  Classification by their stems

·      Grasses.- The stem is thin, soft, and flexible. They don´t have branches.

·      Bushes.- They have a thick and hard stem and low branches.

·      Trees.- They have a trunk, high branches and they are deciduous or evergreen.

Ø  Classification by how they reproduce.        

·      Flowering plants.- They reproduce by seeds.

v Angiosperms..- They reproduce by developing seeds inside the fruit. Examples: roses and rice.

v Gymnosperms.- They reproduce by developing seeds inside cones. Example: pine trees.

·      Non-flowering plants.- They reproduce by spores. Example: mosses and ferns

   4.2.-Reproduction of angiosperms

Ø  Parts of an angiosperm: stigma, stamen, pollen, petal, sepal, ovary, ovule. 

Ø  Pollination

·      Animal pollination.- An animal transfer the pollen from flower to flower.

·      Wind pollination.- The wind blows the pollen from flower to flower.

Ø  Life cycle o fan angiosperm( drawing page 63)

                        1.- Pollen goes into the stigma down to the ovary.

                        2.- A seed develops inside the ovary.

                        3.- The ovary then grows into a fruit with seeds. The petals fall off.

                        4.- The fruit falls, opens, and releases the seeds.

                        5.- The seeds can germinate and new plants grow.

                        6.- The new plant produces flowers.

4. 3.-Plant nutrition and respiration

Ø  Plant nutrition.- Plants make their own food through photosynthesis.

Ø  Plant respiration.- During the day, plants absorb carbon dioxide and expel oxygen. During the night, plants absorb oxygen from the air and expel carbon dioxide.

4.4.-Mammals

-       Mammals are vertebrates. Because they have a backbone.

-       Most mammals have hair or fur.

Ø  Nutrition.- Mammals can be carnivores, herbivores, and omnivores because they have different types of teeth.

Ø  Reproduction.- Most mammals are viviparous which means they are born from their mum´s womb and drink their mum´s milk.

Ø  Respiration.- Mammals breathe with their lungs. Marine mammals such as whales and dolphins breathe through a blowhole.

4.5.-Birds and reptiles

-       Birds are vertebrates. They have wings, beaks, and feathers.

Ø  Birds

·      Nutrition.- They can be carnivores, herbivores and omnivores.

·      Reproduction.- Birds are oviparous which means they are born from eggs.

·      Respiration.- Birds breathe with lungs.

Ø  Reptiles 

-       Reptiles are vertebrates. They have four legs and scales. Some of them have Shell-like turtles.

·      Nutrition.- They are carnivores and omnivores.

·      Reproduction.- They are oviparous.

·      Respiration.- They breathe with lungs.

 4.6.-Amphibians and fish

Ø  Amphibians.- They are vertebrates. They live in fresh Waters or on land near the rivers. They have four legs.

·      Nutrition.- They are carnivores.

·      Reproduction.- They are oviparous. They make adults through the metamorphosis.

·      Respiration.- They offspring breath with gills. Adults breathe with their lungs and with their moist skin.

Ø  Fish.- They are vertebrates. They have scales to protect their bodies. They have a tail and fins.

·      Nutrition.- They are carnivores, herbivores and omnivores.

·      Reproduction.- They are oviparous and lay a lot of eggs at the same time.

·      Respiration.- They breathe with gills. Gills absorb oxygen from the water.

4.7.-Invertebrates

-       Most animals on Earth are invertebrates which means they don´t have a backbone. There are six groups: Arthropods, Molluscs, Echinoderms, Annelids, Cnidarians, and Sponges.

Ø  Arthropods.- Insects, Crustaceans, Arachnids, and Myriapods.

Ø  Molluscs.- Cephalopods, Bivalves, and Gastropods.

Ø  Echinoderms.- Starfish, Sea cucumbers, and Sea urchins.

Ø  Annelids, cnidarians, and sponges. They are the smallest groups.