Biology Lecture Exam 3

What is this

Ctenophors washed up on pacific coast poor movement and fearsome weapons

Eumetazoa

True Animals

Metazoa

Multi Celled animals, has no tissue compared to eumetazoa

Cnidarian Characteristics

Aquatic (Most Marine)

Radial Symmetry

Two Forms (Polyp, Medusae)

Two layers (Epidermis, Gastrodermis)

Stinging cells (nematocysts)

Polyp form of Cnidarians

Attached to a surface, uses tentacles to capture prey

Medusae form of Cnidarians

Free swimming-bell shaped form

Epidermis in Cnidarians contains

Epitheliomuscular Cells

Gland Cells (Secrete sticky substance or gas)

Cnidocytes (Hunting Cell)

Nerve Cells

Gastrodermis within Cnidarians contain

Muscle and glands that produce enzymes

Why is it important for Cnidarians to be radially symmetrical

Since it has poor movement, radial symmetry allows it to sense the same in all directions

Nematocysts

Extend at 2 m/s
Covered by lid or Operculum

Made by Cnidocyte

Cnidocil - Trigger Like cilia

Groups of Cnidarians we talked about

Anthozoa (Flower Animals)
Hydrozoa (Water Serpent Animals)

Schyphozoa (Cup Animal)

Cubozoa (Cube Animal)

Anthozoans

No Medusae

Sea Anemones (Solitary , One Polyp)

Corals (Colonial, many individual polyps)

Hydrozoans

Colonial Soft bodied Cnidarians

Has Polyp + Medusa life Stages (Metagenesis)

Polymorphic Polyps

Polyp stage dominant

Portuguese Man O War

How do hydrozoans asexually reproduce

Budding

Polymorphic

Different polyps with different jobs

Schyphozoa

Jellies

Medusa Stage dominant

Rhopalia (Sense Organs)

Rhopalium

Contains Ocellus used for vison (light detection, and Statocysts for balance/equilibrium

Cubozoa

Box Jellies and Sea Wasps

Medusa is dominant and Box like

Toxic

Complex Rhophalia with camera eyes

Camera Eyes

Human like eyes in cubozoans, contains similar structures to humans

Characteristics of Sponges (Porifera)

Sessile (stationary)

No tissues or organs

Fibrous proteins or spikes in mesohyl

Main Cell Types of Sponges

Choanocytes

Amoebocytes

Epidermis

Choanocytes

Cells in sponges that capture food particles

Ameobocytes

Digest and distribute nutrients from choanocytes

Epidermis of sponge

Also known as pinacoderm, protective outer layer of sponge that helps regulate water flow

How do sponges reproduce

Asexual (Budding, Fragmentation)

Sexual - Choanocytes make sperm and Amoebocytes make eggs (Hermaphroditic

How do sponges disperse?

From larvae that can move

Three types of sponges we talked about

Calcareous Sponges

Glass Sponges
Demosponges

What animal did we talk about that sponges help

Hermit crab

Calcareous Sponge

Calcium carbonate spicules

Glass sponges

Silica spicules with 6 rays

Demosponges

Mostly produce spongin, some have silica spicules

Bilateria

Organisms with bilateral symmetry

Protostomes

Eight cell stage is spiral and determinate, first thing to develop was mouth

Deuterostomes

Eight cell stage is radial and indeterminate, first thing to develop was the anus

Lophotrochozoa

Group of species, Eumetazoa→Bilateria→Protostomia, name based off of larval characters

Lophotrochozoans We talked about

Platyhelminthes

Annelida

Mollusca

Platyhelminthes (Flat worms)

group in lophotrochozoans

Turbellaria (Planarians)

Trematoda (Flukes)

Cestoda (Tapeworms)

What are the three types of Coeloms (Body Cavitys)

Acoelomate

Eucoelomate

Pseudocoelomate

Acoelomate

Body cavity does not exist, space between organs is filled with tissue, example would be a flatworm

Pseudocoelomate

Partial cavity present, not completely lined by mesoderm, example: roundworms

Eucoelomate

True/complete cavity, examples include annelids, mollusks, arthropods, echinoderms, chordates

Turbellaria (Planarians)

Type of platyhelminth, consist of freshwater and terrestrial planarians, free living species

Planarian

Mating is weird because of hermaphrodism species fight to be the impregnater, gut has only one opening

Trematoda (Flukes)

Type of platyhelminth, parasitic species that absorbs nutrients across the body surface due to not having a gut

Schistosoma

Type of blood fluke that causes schistosomiasis

What is this

Life cycle of a blood fluke

Cestoda (Tapeworms)

Parasitic species that has digestive system on outside of them, Hermphroditic, type of platyhelminth

Structures of a tapeworm

Scolex - Head that attaches

Proglottids - Individual body segments, contain reproductive structures

Life cycle of a tapeworm

Egg → Larva in intermediate host → Cyst → Adult in intestine → Gravid proglottids (pregnant) → Eggs

Annelida Characteristics

Circular and Longitudinal muscles

Chitinous Chaetae

Closed circulatory system

Metameric (repeating body parts)

Types of Annelida we talked about

Bristleworms

Earthworms

Leeches

Bristleworms

Bristles (Chaetae/Setae)

Parapodia - appendages

Many construct protective tubes

Marine

Type of Annelida

Earthworms

Live in Damp Terrestrial areas

No parapodia

Clitellum (Thick band around it that secretes mucus)

Aerate Soil

Leeches

Mostly freshwater

Type of Annelida

Clitellum

No chaetae

Secrete anesthetic and anticoagulant that prevents blood clotting (hirudin)

Mollusca Characteristics

Not metameric

Mantle that secretes shell

Radula (tongue)

Foot

Developed Direct eye

Types of Mollusca we talked about

Chitons

Bivalves

Gastropods

Cephalopods

Chitons

Live in Intertidal zones (high-low tide)

8 shell plates

No eyes or antennae

Homing Ability brain (direct path home)

Type of mollusca

Bivavles (Clams, Oysters, Mussels)

2 shells

No head, no radula

Filter feeds through incurrent and excurrent siphons

Pearls

Created by bivalves, it is secreted by the mantle. Most pearls are cultured and can be identified by X-ray

Gastropods (Snails + Slugs)

Lungs, Not gills

Eyes and Antennae

Terrestrial or Freshwater

Undergo Torsion during development

Gastropod torsion

visceral mass and mantle rotate 180°, moving the mantle cavity and anus from the posterior to the anterior end above the head.

Sea Slugs

Type of gastropod

Tentacles

Torsion reversed (moves the mantle cavity and anus back toward the posterior end.)

Glaucus atlanticus (blue dragon)

Type of sea slug that goes after Portuguese Man O’ War, eats their cnidocytes and uses it for itself in its appendages

Nautilus Cephalopods

Living fossils

Pinhole eye (water filled)

No long-term learning

Cephalopods (Cuttlefish, Squid, Octopuses)

Good eyes

Large brains

Long term learning

Movement with jet propulsion

Beaks are modification of radula

How are cephalopod eyes different from human eyes

Signals go straight to the brain, has no blind spots

Chromatophores

Pigment containing cells found in cephalopods that let them change color rapidly

What is special about cephalopod nerve cords

They extend into each arm, each arm has a mind of it’s own

Brooding

Cephalopods keeping eggs with the parent until they hatch, instead of releasing them and leaving.

Cephalopod independent intelligence

cephalopods became intelligent on their own evolutionary path, not because they inherited a large brain from vertebrate ancestors.

Ecdysozoans

Shedding animals, another group derived from Protostomia

Types of Ecdysozoans we talked about

Nematoda

Arthropods

Nematodes

Can’t do peristaltic locomotion, has no circular muscles

Not Segmented

Aquatic, Soil, can be parasitic in both plants or animals

Complete gut (mouth and anus)

Tough skeleton (cuticle) - Molts

Trichinosis

Infection causes by Trichinella spiralis, a type of nematode

What type of organism has the most parasitic worms

Trees

What did the nematologist Nathan Cobb say about nematodes

If everything were to disappear but the nematodes, we would still be able to tell the outline of the earth

Why are fungi predators of nematodes

Some fungi are predatory because they trap and digest nematodes using specialized structures such as constricting rings and sticky nets.

Arthropods

Type of ecydsozoan

Animals with jointed legs and segmented bodies

Cuticle (exoskeleton)

Well-developed sense organs (eyes, antennae)

Open circulatory system

Three types of eyes

Simple Lens eye

Simple corneal eye

Compound eye

Types of Arthropods we talked about

Trilobites

Insects

Crustaceans

Myriapods

Chelicerates

Groups of insects we talked about

Coleoptera

Diptera

Hymenoptera

Lepidoptera

Hemiptera

Orthoptera

Trilobites

Type of arthropod

3 Lobes and 3 Body regions

Extinct marine animal

The three lobes and 3 body regions of Trilobites

Regions = Cephalon (Top), Thorax(middle), Pygidium (bottom)

Lobes = Left and Right Pleural Lobe, Axial lobe

Complete metamorphosis

The larva looks completely different from the adult. Holometabolous organisms do this

Incomplete metamorphosis

The nymph resembles a small adult but usually lacks wings and reproductive organs. Hemimetabolous organisms do this.

Coleoptera

Beetles, Weevils, Fireflies

30% of all animals

Hard outer wings (Elytra)

Diptera

Flies, Mosquitoes

1 pair of flight wings

1 pair reduced wings (balancers

Hymenoptera

Wasps, bees, ants

Many eusocial (colonies)

Stingers

Bent antennae

Two pairs of wings hooked together

Lepidoptera

Butterflies, Moths

Caterpillars damaging to plants

Long probing mouth parts in adults

Hemiptera (True bugs)

Stinkbugs, Bed bugs, Boxelders bugs

Forewings leathery

Piercing mouthparts

Cochineal bug

Hemiptera Bug on cactus that when crushed produces red dye, used for food coloring and lipstick

Orthoptera

Grasshoppers, Crickets

Large Jumping legs

Sound Production

Crustaceans

Type of arthropod

Shrimp, Crabs, Lobsters

Myriapods

Centipedes and Millipedes

Centipede = 1 pair of leg per segment, Venomous, Predators

Millipede = 2 pair of leg per segment, eat dead plant matter

Chelicerates

Type of arthropod

Horseshoe crabs and Arachnids

Arachnids

type of Chelicerate that has 4 pairs of legs(8 total legs)

Scorpion, Spiders, Ticks, Mites

80% of crop pollination is done by who

Bees

What percent of known animal species are arthropods

80%, 1,065,000 million described species and 9 million estimated species (12% described)

Open Circulatory system

A circulatory system in which the blood is not always enclosed within blood vessels and can be pumped into open spaces