Module 2 Vocab Kingdom - Animalia

Symmetry

The arrangement of body parts around a central point or axis.

Radial symmetry

Body parts are arranged around a central axis. The animal can be divided into similar sections through multiple planes passing through the center.

Example: Cnidarians, adult echinoderms.

Bilateral symmetry

The body can be divided into two similar halves, left and right, by only one plane.

Example: Humans, earthworms, insects.

Anterior

The front/head end of an animal.

Posterior

The back/rear end of an animal.

Dorsal

The back or upper side of an animal.

Ventral

The belly or underside of an animal.

Germ layers

Layers of cells formed during embryonic development that eventually develop into the animal's tissues and organs.

Ectoderm

The outer germ layer. Develops into structures such as skin and nervous tissue.

Endoderm

The inner germ layer. Develops into much of the digestive tract and associated organs.

Mesoderm

The middle germ layer. Develops into muscles, connective tissues, and many internal organs.

Coelom

A fluid-filled body cavity completely surrounded by mesoderm.

Acoelomate

An animal with no body cavity between the digestive tract and body wall.

Example: Flatworms.

Pseudocoelomate

An animal with a body cavity that is not completely surrounded by mesoderm.

Example: Roundworms.

Eucoelomate / Coelomate

An animal with a true coelom that is completely surrounded by mesoderm.

Examples: Earthworms, insects, humans.

Protostomate

An animal in which the blastopore develops into the mouth during embryonic development.

Examples: Mollusks, annelids, arthropods.

Deuterostomate

An animal in which the blastopore develops into the anus, with the mouth forming later.

Examples: Echinoderms and chordates.

Endoskeleton

An internal skeleton.

Example: Human bones.

Exoskeleton

A hard skeleton located on the outside of the body.

Example: Arthropod exoskeleton.

Nerve net

A simple nervous system consisting of interconnected nerve cells spread throughout the body.

Example: Cnidarians.

Hermaphrodite

An organism that has both male and female reproductive organs.

Asexual reproduction

Reproduction involving one parent that does not require the fusion of gametes.

Sexual reproduction

Reproduction involving the fusion of male and female gametes.

Herbivore

An animal that primarily eats plants.

Carnivore

An animal that primarily eats other animals.

Omnivore

An animal that eats both plants and animals.

Scavenger

An animal that feeds on dead or decaying organisms.

Parasite

An organism that lives on or inside another organism (host) and obtains nutrients from it, usually harming the host.

Filter feeder

An animal that obtains food by filtering small organisms or particles from water.

Coelom

A fluid-filled body cavity completely surrounded by mesoderm.

Coelomate

An animal that has a true coelom.

Examples: Earthworms, mollusks, arthropods, humans.

Pseudocoelomate

An animal with a body cavity that is not completely lined with mesoderm.

Example: Nematodes/roundworms.

Protostomate

An animal in which the blastopore becomes the mouth during development.

Examples: Mollusks, annelids, arthropods.

Heterotroph

An organism that cannot make its own food and must obtain nutrients by consuming other organisms or organic material.

Animals are heterotrophs.

Germ tissue

The embryonic germ layers that develop into the tissues and organs of an animal.

Examples:

• Ectoderm

• Mesoderm

• Endoderm

Eukaryotic

An organism whose cells contain a nucleus and membrane-bound organelles.

Animals are eukaryotic.

Filter feeder

An organism that obtains food by filtering food particles from water.

Example: Sponge.

Hermaphrodite

An organism that has both male and female reproductive organs.

Examples: Earthworms and many flatworms.

Gastrovascular cavity

A digestive cavity with one opening that functions in both digestion and distribution of nutrients.

Examples: Cnidarians and flatworms.

Radula

A scraping, tongue-like feeding structure found in most mollusks.

It contains tiny teeth used to scrape food.

Amoebocyte

A mobile cell in a sponge that helps with digestion, nutrient distribution, and other functions.

Choanocyte

A specialized sponge cell with a flagellum that creates water currents and traps food particles.

Also called a collar cell.

Spicule

A small skeletal structure in many sponges made of silica or calcium carbonate.

It provides support and protection.

Cnidocyte

A specialized stinging cell found in cnidarians.

It contains a structure called a nematocyst, which can inject toxins and help capture prey.

Medusa

The free-swimming, usually bell-shaped form of a cnidarian.

Example: Jellyfish.

Generally associated with sexual reproduction.

Polyp

The attached, cylindrical form of a cnidarian.

Examples: Sea anemones and corals.

Generally associated with asexual reproduction.

Metanephridia

Excretory structures found in annelids that remove metabolic wastes and help regulate water and salts.

Protonephridia

Excretory structures found in flatworms.

They contain flame cells that help remove wastes and regulate water balance.

Mantle

A layer of tissue in mollusks that covers the visceral mass and usually produces the shell.

Spiracles and trachea

Structures used by terrestrial arthropods for gas exchange.

• Spiracles: Openings in the body

• Trachea: Tubes that carry air directly to tissues

Chitinous exoskeleton

A hard external skeleton made primarily of chitin.

It provides:

• Protection

• Support

• Attachment for muscles

• Prevention of water loss in terrestrial arthropods

Cephalization

The concentration of sensory organs and nervous tissue toward the head of an animal.

It is associated with bilateral symmetry.

Tube feet

Small, hydraulic structures of echinoderms used for:

• Movement

• Feeding

• Attachment

• Gas exchange

They are part of the water vascular system.

Closed circulatory system

Blood remains inside blood vessels and is pumped by a heart.

Examples: Annelids and chordates.

Dorsal nerve cord

A nerve cord located along the dorsal/back side of chordates.

In vertebrates, it develops into the spinal cord.

Notochord

A flexible supporting rod found in chordates.

In vertebrates, it is largely replaced by the vertebral column during development.

Vertebrate

A chordate with a vertebral column/backbone.

Examples: Fish, amphibians, reptiles, birds, mammals.

1. Describe how the amoebocyte and choanocyte function in the digestive process of a sponge.

Choanocytes have flagella that create water currents through the sponge. They trap food particles from the water using their collar-like structures.

The choanocytes digest or transfer food particles to amoebocytes.

Amoebocytes move throughout the sponge and distribute nutrients to other cells. They also help with digestion and other functions.

Short answer:

Choanocytes trap and digest food particles, while amoebocytes distribute nutrients throughout the sponge.

Give the advantages of an alternation of generation between the medusa and polyp stages seen in Cnidarians.

The two forms allow cnidarians to use different methods of reproduction and different habitats.

Polyp:

• Usually attached to a surface

• Usually reproduces asexually

• Can produce new individuals

Medusa:

• Free-swimming

• Usually reproduces sexually

• Allows the organism to spread over greater distances

Answer: Alternating between polyp and medusa stages allows cnidarians to reproduce both sexually and asexually and allows them to take advantage of both attached and free-swimming lifestyles.

Discuss the mode of transmission and life cycle of the parasitic worm Ascaris.

Ascaris is a parasitic roundworm that lives in the human intestine.

1. Adult worms live in the intestine.

2. Eggs are released in the host's feces.

3. Eggs contaminate soil, food, or water.

4. A person accidentally ingests the eggs.

5. Larvae hatch and penetrate the intestinal wall.

6. They travel through the bloodstream to the lungs.

7. Larvae move up the respiratory tract and are swallowed.

8. They return to the small intestine.

9. They mature into adult worms.

10. Adults reproduce and produce eggs, beginning the cycle again.

Important transmission: Feces→contaminated food/water/soil→ingestion

Describe the life cycle of the pork tapeworm.

1. An infected human has adult tapeworms in the intestine.

2. Eggs/proglottids leave the human in feces.

3. A pig ingests the eggs from contaminated food, water, or soil.

4. Larvae develop and travel into the pig's muscles.

5. Larvae form cysts called cysticerci in the pig's muscles.

6. A human eats undercooked pork containing cysticerci.

7. The cysticerci develop into adult tapeworms in the human intestine.

8. The adult tapeworm produces eggs/proglottids.

9. The cycle starts again.

Important: Human→pig→human

Eating undercooked infected pork causes intestinal tapeworm infection.

Describe the three major parts of a mollusk's body

Muscular foot

Used primarily for movement and attachment.

Visceral mass

Contains the animal's internal organs, including digestive and reproductive organs.

Mantle

A layer of tissue that covers the visceral mass and usually secretes the shell.

List four major characteristics that all chordates must possess.

• Notochord

• Dorsal hollow nerve cord

• Pharyngeal slits/pouches

• Post-anal tail

Porifera

"Pore-bearing"

Sponges

Cnidaria

Named for cnidocytes/stinging cells

Jellyfish, corals, sea anemones, hydra

Platyhelminthes

"Flat worms”

Planarians, tapeworms, flukes

Nematoda

"Thread-like"

Roundworms, hookworms, Ascaris

Annelida

"Little rings"

Earthworms, leeches, polychaetes

Mollusca

"Soft-bodied"

Snails, clams, squid, octopus

Arthropoda

"Jointed feet"

Insects, spiders, crabs, lobsters

Chordata

Animals possessing chordate characteristics

Fish, amphibians, reptiles, birds, mammals

Echinodermata

"Spiny skin"

Sea stars, sea urchins, sand dollars, sea cucumbers

Four Bird Adaptations for Flight

1. Hollow/lightweight bones

2. Feathers

3. Wings

4. Large flight muscles

What is the function of the "pit" on a pit viper?

The pit is a heat-sensing organ located between the snake's eye and nostril.

It detects infrared radiation/heat from warm objects, allowing the snake to locate prey, especially in darkness.

Three pit vipers found in South Carolina:

1. Copperhead

2. Cottonmouth (water moccasin)

3. Timber rattlesnake

Echinoderm Water Vascular System

The water vascular system is a hydraulic system used by echinoderms.

Water enters through a structure called the madreporite.

The water moves through a series of canals

Animal Anatomy: Planaria

Eyespots

Detect light.

Auricles

Lateral projections that contain sensory cells and help detect chemical and environmental stimuli.

Ganglia

Clusters of nerve cells that act as a simple brain-like control center.

Longitudinal nerve cords

Carry nerve signals along the length of the body.

Pharynx

A muscular tube used to take in food.

Mouth

Opening through which food enters.

Gastrovascular cavity

Digests food and distributes nutrients throughout the body.

Flame cells / Protonephridia

Remove metabolic waste and help maintain water balance.

Porifera

Symmetry - Asymmetrical

Germ Layers - No true layers

Body Cavity - None

Digestive system - No

Circulation - None

Cnidaria

Symmetry - Radial

Germ Layers - 2

Body Cavity - None

Digestive System - Gastrovascular Cavity

Circulation - None

Platyhelminthes

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Acoelomate

Digestive System - Gastrovascular cavity

Circulation - None

Nematoda

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Pseudocoelomate

Digestive System - Complete

Circulation - None

Annelida

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Coelomate

Digestive System - Complete

Circulation - Closed

Mollusca

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Coelomate

Digestive System - Complete

Circulation - Usually open

Arthropoda

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Coelomate

Digestive System - Complete

Circulation - Open

Echinodermata

Symmetry - Radial as adults

Germ Layers - 3

Body Cavity - Coelomate

Digestive System - Complete

Circulation - Water vascular system

Chordata

Symmetry - Bilateral

Germ Layers - 3

Body Cavity - Coelomate

Digestive System - Complete

Circulation - Closed