Animal Diversity and Developmental Patterns

Body cavity NOT fully lined by mesoderm, found in roundworms.

Body cavity fully lined by mesoderm, found in humans and earthworms.

Fluid-filled body cavity providing support and movement, found in soft-bodied animals like jellyfish and earthworms.

Repeated segments of the body, present in insects, earthworms, and vertebrates.

Specialized limbs of the body.

Network of nerves coordinating movement and responses to stimuli.

Movement using cilia, found in flatworms and paramecia.

Animals that filter food particles from the water.

All animals share a common ancestor, evidenced by DNA sequencing showing similar genes and cellular structures.

A type of cell division where cells split symmetrically, found in organisms like humans and starfish.

A type of cell division where cells split at an angle, found in creatures like snails and earthworms.

Animals with two germ layers (ectoderm and endoderm), like jellyfish, exhibit simpler body plans.

Animals possessing three germ layers (ectoderm, mesoderm, endoderm), like humans and worms, exhibit more complex body plans.

A body cavity that provides internal space for organs and supports movement, found in many animal groups.

Animals with body parts arranged around a central axis, allowing them to interact with their environment from all directions. Example: jellyfish.

Organisms that live in or on a host and obtain food at the host's expense.

Animals that feed on dead organic material.

Distinct developmental stages during an animal's life cycle, often serving different functions.

A juvenile form that is usually different in form and function from the adult.

A process in which an animal undergoes significant physical changes to transition from a juvenile to an adult.

Metamorphosis where the juvenile resembles the adult

Metamorphosis with a pupal stage where the animal undergoes dramatic changes.

The ability of a species to spread to new environments, reduce competition, and maintain genetic diversity.

Dispersal by wind, like seeds carried by the breeze or butterflies.

Dispersal by water currents, like marine larvae.

Dispersal by animals, like birds spreading seeds after eating fruit.

A complex series of stages in a parasite's life cycle, often involving multiple hosts.

A parasite using multiple hosts in its life cycle, with each host providing different benefits.

Forms such as eggs, larvae, or cysts released by parasites to survive outside a host and spread.

Parasites manipulating their hosts' behavior to spread to new hosts, like wasps making a host act oddly.

Genetically identical animals joined together, forming a larger unit, like corals.

These diverse animals have a simple bilayered body, lack any true organs or tissues, and feed by absorbing nutrients from algae or detritus.

Ctenophores are carnivores that catch small prey, like plankton, using sticky cells called colloblasts.

They contain nematocysts, tiny harpoon-like structures that inject toxins into their prey.

Cnidarians have two main body forms: polyps, which are sessile and attached, and medusas, which are free-swimming and bell-shaped.

A jelly-like substance that fills the space between the epidermis and gastrodermis in Cnidarians.

Sessile Cnidarians, like corals and sea anemones, that are important contributors to marine ecosystems.

True jellyfish, with a medusa-dominated life cycle and free-swimming.

Cnidarians are carnivorous animals that use specialized stinging cells called cnidocytes to capture and paralyze their prey.

The earliest ancestor of all animals, its exact location within the evolutionary tree is still debated, with sponges, ctenophores, and placozoans as potential candidates.

Organisms, like sponges, that lack specialized tissues or organs, with their bodies composed of loosely organized cells.

Specialized cells in sponges that create water currents and capture food particles.

Specialized cells in sponges that transport nutrients and contribute to reproduction.

Animals with two embryonic tissue layers: ectoderm and endoderm, contributing to simpler body plans.

The evolutionary relationships among different animal groups, with an emphasis on their evolutionary history and connections.

Contradictions between data based on gene sequences and traditional classifications based on physical structures, leading to alternate interpretations about early animal evolution.