UNIT 3

LIVING THINGS

UNIT 3 – LIVING THINGS

1. VERTEBRATES1.1 NUTRITION

1.2 REPRODUCTION

1.3 RESPIRATION

2. INVERTEBRATES2.1 MOLLUSCS

2.2 JELLYFISH

2,3 SPONGES

2,4 ECHINODERMS

2.5 ANNELIDS

2.6 ARTHROPODS

3. PLANTS3.1 NUTRITION AND REPRODUCTION

3.2 PHOTOSYNTHESIS

1. VERTEBRATESA vertebrate is an animal that has a backbone and a skeleton. Vertebrate animals includehumans.

Human backbone Different animals’ skeletons

Vertebrates comprise five big groups: mammals, amphibians, reptiles, birds and fish.

Mammals are vertebrates that are born from their mother’s uterus.

Such as:

cat lion fox polar bear human being

dolphin whale

Amphibians are vertebrates that can live both on land and in water.

Such as:

frog salamander newt toad

Reptiles are vertebrates that have their skin covered with scales or bonyplates.

Some examples of reptiles are:

crocodile/alligator lizard tortoise snake

Birds are vertebrates that have wings and feathers.

Some birds are:

sparrow vulture swallow eagle

Fish are vertebrates that live in water and have fins and scales.

Some examples of fish would be:

cod hake shark salmon

1.1 NUTRITIONAccording to what they eat, we can diferenciate three big groups among vertebrates:

Carnivores are animals that get food from killing and eating other animals. The bigger thecarnivore, the more it has to eat.

Herbivores are animals that eat only plants. So that they usually eat parts of plants, seeds, fruitsand vegetables.

Omnivores are animals that eat both other animals and plants. So that, added to animals theyalso eat parts of plants, seeds, fruits and vegetables.

Mammals can be carnivores, herbivores and omnivores.Amphibians are carnivores.Reptiles are carnivores.Most birds are omnivores and a few are carnivores.Most fish are carnivores or omnivores.

1.2 REPRODUCTION

All mammals are born directly from their mother (the mother’s uterus) they areviviparous.

Mammals are also different to other animals because they produce milk to feed theirbabies and look after them for a long time.

The other four groups of vertebrates (amphibians, reptiles, birds and fish) reproduce by layingeggs, so that they are oviparous. Sometimes these eggs are hard, such as chicken’s eggs.

And sometimes they are soft, such as frog and fish eggs.

EXERCISES1. In teams, decide whether the following animals are vertebrates or invertebrates. If theyare vertebrates write which group they belong to (mammals, reptiles, amphibians, birds orfish) Two are given as an example.

bat, bee, beetle, butterfly, camel, cow, crocodile, dinosaur, dog, dolphin, donkey, eagle, goat,jellyfish, salmon, cod, kangaroo, lizard, mouse, frog, octopus, parrot, penguin, salamander, polarbear, rabbit, sheep, swan, tortoise, zebra.

ANIMAL VERTEBRATE INVERTEBRATE GROUP NUTRITION

batbeebeetlebutterflycamelcowcrocodiledogdolphindonkeyeaglegoatjellyfishsalmoncodkangaroo lizardmouse frogoctopusparrotpenguinsalamanderpolar bear

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Mammal

Omnivore

rabbitsheepswantortoisezebra

2. Place the following animals in the group they belong to according to how they are born.Two are given as an example.

bat, bee, beetle, butterfly, camel, cow, crocodile, dinosaur, dog, dolphin, donkey, eagle, goat,jellyfish, salmon, cod, kangaroo, lizard, mouse, frog, octopus, parrot, penguin, salamander, polarbear, rabbit, sheep, swan, tortoise, zebra.

ANIMAL VIVIPAROUS OVIPAROUS

batbeebeetlebutterflycamelcowcrocodiledinosaurdogdolphindonkeyeaglegoatjellyfishsalmoncodkangaroo lizardmouse frogoctopusparrotpenguinsalamanderpolar bearrabbitsheepswantortoisezebra

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1.3 RESPIRATIONAll animals need oxygen to live. Mammals, reptiles and birds get oxygen from the air, theybreathe with lungs.

Dog’s lungs (mammal)

Horse’s lungs (mammal)

The lizard has got only one lung (reptile) Crocodile’s lungs (reptile)

Duck’s lungs (bird) Sparrow’s lungs (bird)

Fish use gills to get oxygen from the water. Gills take the oxygen out of the water.

Amphibians have external gills when they are young and live in water and later developlungs to live on land.

larval salamander’s external gills adult frog’s lungs

EXERCISES

1. Choose the odd one out and write the reason why it does not fit in the group.The first group is given as an example.a) Tiger, spider, eagle, bee Because the others are carnivores.b) Fish, frog, bear, lizardc) Cow, tiger, butterfly, whaled) Pig, sheep, human, beare) Dolphin, snake, crocodile, fishf) Eagle, squirrel, hen, duck

2. Complete the chart.

ANIMAL GROUP RESPIRATION REPRODUCTION NUTRITION

goat

alligator

amphibian

gills

omnivore

EXERCISES ANSWERS

1. Choose the odd one out and write the reason why it does not fit in the group. Thefirst groupa) Tiger, spider, eagle, bee Because the others are carnivores.b) Fish, frog, bear, lizard The bear is viviparous, the othersoviparousc) Cow, tiger, butterfly, whale The butterfly is an invertebrate, the others verte-

bratesd) Pig, sheep, human, bear The sheep is herbivore, the others omnivorese) Dolphin, snake, crocodile, fish The dolphin is viviparous, the others oviparousf) Eagle, squirrel, hen, duck The others are birds, the squirrel is a mammal

2. Complete the chart.

ANIMAL GROUP RESPIRATION REPRODUCTION NUTRITION

goat MAMMALS LUNGS VIVPAROUS HERBIVORE

alligator REPTILE LUNGS OVIPAROUS CARNIVORE

FROG amphibian GILLS LUNGS OVIPAROUS OMNIVORE

COD FISH gills OVIPAROUS CARNIVORE

HUMAN MAMMALS LUNGS VIVPAROUSZ omnivore

2. INVERTEBRATES97% of all animals are invertebrates and they almost live everywhere. Here are the sixgroups of invertebrates:

1.1 MOLLUSCS

Molluscs have a soft muscular body, often protected by a hard shell.

Some, such as the snail or the slug, live on land.

snail slug

But most, like the mussel, clam, octopus and squid live in oceans and seas.

mussel clam octopus squid

1.2 JELLYFISHJellyfish have a soft body, called the umbrella and often long tentacles.

There is a hole under their umbrella that is both mouth and anus.

They live in seas and oceans.

1.3 SPONGESSponges have a soft body covered with little holes that they useto take in oxygen and food through them.

There are lots of known species of sponges with different shapes and colours.

They live in seas and oceans. More specifically, the stay on the seabed.

1.4 ECHINODERMSEchinoderms are protected from predators by hard skin or spikes. They are often brightly coloured.

They live in seas and oceans.

Starfish are echinoderms, they usually have five arms but can have up to forty.

1.5 ANNELIDSAnnelids have a long soft body divided into segments.

Some, like the earthworn, live on land. Others live in seas and oceans.

1.6 ARTHROPODSAlmost all animals on Earth are arthropods. The biggest group is insects.

They have a head, thorax and abdomen, jointed legs and a protective exoskeleton.

They live in water, on land, in the air and underground.

EXERCISES1. Match the half sentences

a) They are brightly coloured... 1. to take in oxygen and foodb) They have shells… 2. to frighten away predatorsc) They have little holes… 3. to capture animals to eatd) They have tentacles 4. to stop other animals eating them

2. Find the mistake and correct the sentences about invertebratesa) Most invertebrates are very bigb) There are many more vertebrates than invertebrates on the Earthc) All invertebrates have a backboned) Invertebrates only live in watere) Molluscs are the largest group of invertebrates

3. Fill in the chart giving a description for each group of invertebrates.GROUP BODY DESCRIPTION WHERE THEY

LIVEANIMAL

MOLLUSCS Soft muscular body. Somehave a shell

Seas and oceansor on land

Squid

JELLYFISH

SPONGES

ECHINODERMS

ANNELIDS

ARTHROPODS

EXERCISES ANSWERS1. Match the half sentences

a) They are brightly coloured... 1. to take in oxygen and foodb) They have shells… 2. to frighten away predatorsc) They have little holes… 3. to capture animals to eat

d) They have tentacles 4. to stop other animals eating them