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What is 1 + 3?
Science Chapter 1 Lesson 3
An animal with a segmented backbone.
Animals with nerve chords running down their backs.
bone and cartilage
endoskeletons are made of this.
Examples are trout, salmon, tuna, goldfish. They have hard, bony skeletons and breathe through gills.
Rays, skates and this sliky shark have skeletons made of these.
They have jaws, feathers and hard, bony skeletons. They breathe through lungs.
They have jaws, scales and hard bony skeletons.
examples of reptiles
snales, turtles, alligators and lizards.
They breathe through lungs and feed their young on mother's milk. Most live on land.
examples of mammals
humans, dogs, horses and whales.
Animals with four feet
Animals with two feet.
animals without backbones
More than 95 of animals are these
An invertabrate that has an external skeleton, a segmented body, and jointed appendages. Examples are insects, spiders, crab and shrimps.
flat and round worms
they live in water, in damp soil or inside other animals.
Examples are jellyfish, hydras and corals
these belong to a phylum called Porifera.
Examples are sea stars and sea urchins.
examples are clams, snails, oysters, squid and scallops.
these are invertebrates with tough exoskeletons
tough outer skeletons cover the organisms bodies and protect the animals from danger.
crustaceans, insects and arachnids
groups of arthropods
crabs, shrimp and lobsters
examples of crustaceans
most abundant animals in the ocean, there are more than 30,000 species.
largest group of arthropods.
these consists of a head, thorax and abdomen.
antennae and eyes
these help an insect sense the environment.
there include spiders, ticks, scorpions and mites.
these have four pairs of appendages, one or two body sections and no antennae
predators that feed mainly on insects.
parts of arthropods
abdomen, jointed legs, thorax, antennae and head
largest animals on earth
there are in the vertebrate class, not invertebrates.
These have stinging cells to capture fish
these have bodies separated into compartments.
Classes of vertebrates
reptiles, amphibians, birds and mammals.
these have soft skeletons and gills. specials include the hagfish and lamprey
lesson main idea
animals are classified according to whether or not they have backbones.