Lecture 16

Flashcards to review key concepts from the Animalia lecture.

Animals are __, heterotrophic eukaryotes with tissues that develop from embryonic layers.

multicellular

Animals obtain energy and nutrients by __ other organisms.

eating

Animals digest food __ after ingestion, in contrast to fungi.

internally

The __ stage usually dominates the life cycle of most animals.

diploid

Many animals have a larval stage that is __ and morphologically distinct from the adult stage.

sexually immature

The common ancestor of all animals likely lived about __ million years ago.

770

Choanoflagellates are closely related to animals based on __ and molecular evidence.

morphological

Most animals share a unique family of regulatory genes known as __ genes.

Hox

The first generally accepted macroscopic animal fossils date from about __ million years ago.

560

The first evidence of __ is found in fossils of the Ediacaran period.

predation

What are animals classified as?

Animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers.

How do animals obtain energy and nutrients?

Animals obtain energy and nutrients by eating other organisms.

How do animals digest food?

Animals digest food internally after ingestion, in contrast to fungi.

What stage usually dominates the life cycle of most animals?

The diploid stage usually dominates the life cycle of most animals.

What is a distinguishing feature of the larval stage in many animals?

Many animals have a larval stage that is sexually immature and morphologically distinct from the adult stage.

When did the common ancestor of all animals likely live?

The common ancestor of all animals likely lived about 770 million years ago.

What evidence suggests that choanoflagellates are closely related to animals?

Choanoflagellates are closely related to animals based on morphological and molecular evidence.

What unique family of regulatory genes do most animals share?

Most animals share a unique family of regulatory genes known as Hox genes.

When do the first generally accepted macroscopic animal fossils date from?

The first generally accepted macroscopic animal fossils date from about 560 million years ago.

What is the first evidence of predation found in?

The first evidence of predation is found in fossils of the Ediacaran period