Animal Diversity & Systems

From Invertebrates to Vertebrates

The “Big 5” of Kingdom Animalia

• Multicellular• Eukaryotic• Heterotrophic• Motile• No cell walls

Taxonomy Review

• Kingdom– Phylum (or Division)

- Class -Order

- ??? - ??? - ???

Which group is the largest? Which is the smallest?

Student Misconceptions:

1. SpongeBob really wears “so called” square-pants.

2. SpongeBob can actually digest “crabby patties”.

3. SpongeBob can “run and play” as seen on TV.

Phylum Porifera• Ex: sponges• aquatic• No tissues/organs

• Filter feeders (intracellular digestion)

• Diffusion w/surrounding water

• Hard spicules for protection

Digestive System• Intracellular digestion

– Can only eat tiny foodparticles

(smaller than cells)– Ex: sponges

• Extracellular digestion– Can eat big food; must

have gut of some type– Ex. All other animals

Digestive System• Incomplete digestive

system– Only one opening;

inefficient!– Ex: jellyfish &

flatworms• Complete digestive

system– Two openings

(mouth & anus)– Ex: all other higher

animals!

Phylum Cnidaria

• aquatic• Radial symmetry• Stinging cells to get food• Incomplete digestive

cavity• Simple muscle & nerve

cellsEx: jellyfish, corals, sea anemones

Animals exhibit symmetry:• Asymmetry

– No symmetry– ex: sponges

• Radial Symmetry– No front/back, only top/bottom– Ex: jellyfish

• Bilateral Symmetry– Front/back/top/bottom– Ex: most all other animals

• Nerves allow for movement and sensory input• Cephalization – is the centralization of nerve tissue to

the head region – better movement/ brain formation

Phylum Platyhelminthes

• Flat!• Aquatic or parasitic• Bilateral – head region• Tissues, but no organs

• Incomplete digestive system

• Simple muscles & nerves

• No body cavity

Ex: Planaria (free-living); tapeworms

& flukes (parasitic)

Having a body cavity allows for more specialization of organs:

• Acoelomates– No cavity; Ex:

flatworms

• Pseudocoelomates– “false” cavity; Ex:

round worms

• Coelomates– True cavity; Ex:

earthworms & all higher

Phylum Nematoda

• Ex: roundworms, pinworms• round• Most are parasitic

• Complete digestive system• Bilateral symmetry• Pseudocoelomate

Nervous System - Nerves allow for movement and sensory input•Some animals like sponges, have no nervous tissues.•Others, like the jellyfish have some cells to detect stimuli.•Most animals developed nerves and a brain.

Phylum Mollusca

•Soft bodies•Mantle secretes shell•Bilateral symmetry•Coelomate•Complete digestive system

Phylum MolluscaClass Gastropoda

“stomach-foot” molluscs

ex: snails & slugs sensory tissue

1 shell* herbivores/predators

Phylum MolluscaClass Bivalvia

“two shell” molluscs

ex: clams, oysters, scallops

filter feeders aquatic

Phylum MolluscaClass Cephalopoda

“head-foot” molluscs closed circulatory system

ex: octopus, squid, nautilus brain; great vision & mvmt

No shell use ink against predators

Phylum Echinodermata“spiny skin”

Sea stars; sea urchins; sand dollars; sea fans

Complexity of Form

• Coelomates– True cavity; Ex:

earthworms & all higher

– Body sections are sign of more complexity in function

– Appendages (like arms, legs and antennae show complexity too

Compartments allow for specialization of function

Phylum Annelida• Ex: earthworm, leech• Segmented (ringed)• Typically in soil; some

parasitic or aquatic

• Coelomate – true cavity• Brain & sensory tissue• Hermaphrodites

Skeletal – Muscular System

• Exoskeletons - like on arthropods

• Endoskeletons - like bones

Muscles allow for movement, but must pull on something rigid

- could pull on…- water filled tubes - shells

Phylum Arthropoda“jointed feet”

• Jointed appendages• Body segments• Exoskeleton of chitin• Coelomate• Bilateral symmetry

Class Insecta

Phylum ArthropodaClass Insecta

• Wings & 6 legs• 3 body segments• Compound eyes• Trachea & spiracles for

respiration• Terrestrial

Most numerous group of animals and most endangered – many

specialized adaptations

Phylum ArthropodaClass Arachnida

Spiders

Scorpions

Mites

Ticks

Phylum ArthropodaClass Arachnida

• 8 legs• No wings or antennae• 2 body segments• Compound/simple eyes• Some spin silk/webs• Carnivores/parasites• Terrestrial

Abdomen Cephalothorax

Phylum ArthropodaClass Crustacea

Crayfish

Lobsters

Crabs

Shrimp

Roly-polies

Phylum ArthropodaClass Crustacea

• 10 legs (front usually modified to catch prey)

• 2 sets antennae• 2 body segments• Gills for respiration• Aquatic; “swimmerets”

(roly-polies = terrestrial)

Phylum ArthropodaClass Chilopoda

• Ex: centipedes• 1 pair legs per segment• 1 set antennae• Predators, often poison

Phylum ArthropodaClass Diplopoda

• Ex: Millipedes• 2 pair legs per segment• 1 set antennae• Herbivores/detritivores

(eat dead stuff)

The End

Embryo Formation

• Label on your paper:A = zygote E = blastula G = gastrula

Animal Reproduction• Sexual – exchange gametes• Asexual – no gamete exchange• Internal Fertilization – usually smaller #s of

offspring; more parental care• External Fertilization - usually larger #s of

offspring; less parental care

Embryo Formation

• Label on your paper:A = zygote E = blastula G = gastrula

Circulatory System• Simple diffusion

– Nutrients move in and out from surrounding water

• Open circulatory system– Have heart but no blood

vessels, just cavities for blood

• Closed circulatory system– Have heart & blood

vessels

Respiratory System• Some animals move gases by simple diffusion.• Most have developed special structures to

move gases. These include:– skin, spiracles, book lungs, gills, lungs

Phylum Echinodermata• Radial symmetry*• Water vascular system =

system of tubes for mvmt & transport

• No brain; has nerve ring• Regeneration

Complete Metamorphosisin Insects

Organ systems in animals work together to do certain things:

• Integumentary – Protects against pathogens; helps regulate body temperature, keratin formed from epidermis waterproofs skin, forms hair and nails; body covering

• Skin; epidermis, keratin; dermis, sebaceous glands (oil) and sweat glands

• Skeletal – Provides structure; supports and protects internal organs; axial includes skull, vertebral column and rib cage; appendicular includes limbs; support; what muscles pull on

• 206 bones; osteocytes, axial skeleton, appendicular skeleton, joints; fixed, moveable; ligaments, tendons

Organ systems in animals work together to do certain things:

• Muscular – Provides structure; supports and moves trunk and limbs; moves substances through body; skeletal – conscious movement; cardiac – heart; smooth – unconscious movement like digestive tract; movement

• Muscles (skeletal, cardiac, and smooth) • Nervous – Cerebrum controls intelligence/creativity; cerebral

cortex controls and coordinates body movements and senses; medula oblongata helps monitor and maintain other body systems (homeostasis); somatic n. system controls voluntary system; autonomic n. system controls activities that are not under conscious control

• Brain; cerebrum, cerebral cortex, cerebellum, medulla oblongata; spinal cord, nerves; cell body, dentrites, axon; sensory neurons, motor neurons, synapse, sense organs, receptors; five senses.

Organ systems in animals work together to do certain things:

• Circulatory – Transports nutrients, and wastes to and from all body tissues. Pulmonary circulation – right side of heart; systemic circulation – left side of heart; rbc – hemoglobin/O2; wbc – immune response; platelets – clotting.

• Heart; right atrium/ventricle, left atrium/ventricle; blood vessels – veins, arteries, capillaries; blood – red blood cells, white blood cells, platelets.

• Respiratory – Carries air into and out of lungs, where gases (oxygen and carbon dioxide) are exchanged, breathing is mechanical movement of air, respiration is diffusion of O2/CO2 across membranes; gas exchange

• Nose, mouth, pharynx, larynx, trachea, bronchi, bronchioles, alveoli, diaphragm

Organ systems in animals work together to do certain things:

• Digestive – Stores and digests food; absorbs nutrients; eliminates waste, stomach – HCL, pepsin; pancreas – enzymes, insulin; liver – bile (breaks down fats); break down food

• Mouth, esophagus, stomach, liver, pancreas, small and large intestines

• Excretory – Eliminates waste; maintains water and chemical balance; ammonia converted to urea

• Kidneys, ureters, bladder, urethra, skin, lungs

• Reproductive – Produces ova and milk in females, sperm in males, and offspring after fertilization

• Ovaries, uterus, mammary glands (in females), testes (in males)

Organ systems in animals work together to do certain things:

• Immune – Provides protection against infection and disease

• Lymph nodes and vessels, white blood cells (lymphocytes)

• Endocrine – Maintains homeostasis; regulates metabolism, water and mineral balance, growth and sexual development, and reproduction

• Glands ex: adrenal – metabolism, stress; thyroid – growth/develop; pancreas – insulin; hypothalamus – controls pituitary; testis – testosterone; ovary - estrogen