Invertebrates

Animals whose embryonic development occurs inside an egg that remains within the mother's womb are called...

• Viviparous

• Ovoviviparous

• Oviviparous

• Oviparous

Invertebrates...

• are primitive animals

• are very underdeveloped

• are less evolved than vertebrates

• have amazing adaptations

Answer explanation

Invertebrates have evolved over millions of years. Even without considering this, evolution is not synonymous with superiority.

Some invertebrates have the ability to regenerate their limbs or produce bioluminescence.

Invertebrates

• are insects

• are worms and insects

• make up 6 phyla

• make up many phyla

Answer explanation

Invertebrates include more than 30 different phyla. The most well-known is Arthropods (which includes insects, among others), but there are many more.

We are going to study: Poriferans, Cnidarians, Platyhelminthes, Nematodes, Annelids, Echinoderms, Arthropods, and Mollusks.

Which is the "bigger" phylum of invertebrates?

• Cnidarians

• Arthropods

• Worms

• Molluscs

Answer explanation

Arthropods represent 80% of all known animal species.

Invertebrates...

• are very small

• have a very underdeveloped nervous system

• have a soft body and no protection

• can be very large or very smal

Answer explanation

Invertebrates come in a wide range of sizes. A centipede can be larger than a mouse.

Invertebrates have...

• External skeletons (Exoskeletons)

• No skeleton

• Internal Skeletons (Endoskeletons)

• All of the above

Answer explanation

Some invertebrates have:

• Endoskeleton (e.j, Sea urchins)

• Exoskeleton (e.j, Arthropods)

• No skeleton (e.j, Jellyfish)

Which phylum of invertebrates has radial symmetry? (2 Answers)

• Cnidarians

• Echinoderms

• Poriferans

• Molluscs

Which invertebrates can reproduce asexually?

• Poriferans, Cnidarians, Platyhelminthes, and some Echinoderms

• Poriferans, Cnidarians, and Platyhelminthes

• Poriferans, Arthropods, and Mollusks

• Cnidarians and Echinoderms

Regarding the body temperature of invertebrates (2 Answers)

• They are incapable of regulating their body temperature.

• They can generally survive in extreme environments.

• They are capable of regulating their own body temperature.

• They generally cannot survive in extreme environments

Answer explanation

They are ectotherms, which means they cannot regulate their body temperature. This generally prevents them from surviving in extreme environments.

However, some invertebrates, like tardigrades, can withstand extreme conditions… even outer space!

What is the ambulacral system?

• A muscular system that allows movement in echinoderms

• The primitive digestive tract in annelids

• A network of tubes through witch water circulates

• The system by which cephalopods expel water to move. It consists of the siphon

Answer explanation

The ambulacral system is a network of tubes through which water circulates, exclusive to echinoderms.

It enables locomotion, respiration, feeding, and helps sense the environment.