Kingdom Animalia and Invertebrate Phyla Overview

A collection of flashcards covering key concepts from the lecture on Kingdom Animalia and the Invertebrate Phyla, helping students prepare for their exam.

What defines an animal?

Animals are multicellular organisms that consume food, move at some point in their lives, and have specialized tissues.

What is a key characteristic of animal cells?

Animal cells are eukaryotic, meaning they have nuclei and are complex.

What does it mean for animals to be heterotrophic?

It means animals must eat food for energy and do not perform photosynthesis.

Which animal phylum is known to have no true tissues?

Porifera, or sponges, which have no true tissues.

What is the significance of Hox genes in animals?

Hox genes are body plan controllers that determine the placement of limbs, organs, and the head.

What are the characteristics of bilateral symmetry?

Bilateral symmetry refers to a body plan that is symmetric along a vertical plane, leading to the development of a head (cephalization).

What are the three main germ layers in triploblastic animals?

Ectoderm (skin and nerves), mesoderm (muscle and organs), endoderm (gut lining).

How do protostomes differ from deuterostomes in development?

In protostomes, the mouth develops first; in deuterostomes, the anus develops first.

What is metamerism?

Metamerism is the division of the body into repeating units, found in segmented animals like annelids and arthropods.

Which group of invertebrates are known for having a true coelom?

Annelids, which have a true body cavity.

What distinguishes mollusks from other invertebrates?

Mollusks have a soft body, many possess shells, and share three main body parts: muscular foot, visceral mass, and mantle.

What feature is unique to arthropods?

Arthropods have an exoskeleton made of chitin and jointed appendages.

What is a common trait found in echinoderms?

Echinoderms exhibit radial symmetry as adults and have a water vascular system.

What are the defining features of chordates?

Chordates possess a notochord, dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some stage of development.

What characterizes animals in phylum Nematoda?

Nematodes are pseudocoelomates with bilateral symmetry, a complete digestive system, and they typically exhibit thrashing motion.

What is the primary method of reproduction for flatworms in phylum Platyhelminthes?

Flatworms can reproduce both asexually (fragmentation) and sexually as they are hermaphrodites.

What does 'diploblastic' mean in the context of Cnidarians?

Diploblastic organisms have two germ layers: ectoderm and endoderm.