BioDiversity Set 20 - PHYLLUM BIODIVERSITY

Last Set!!

What are the key characteristics of Phylum Echinodermata?

• Colemates

• Bilateral

• DUETEROSOMES

• NOT segmented

Includes starfish, sea cucumbers, sea urchins

Why are animals, like starfish, under the Phylum Echinodermata described as bilateral when the adult forms have radial symmetry?

It is because echinoderm larvae have bilateral symmetry, which is why they are NOT defined as having radial symmetry

What is the physical structure that all Echinoderms have?

All have tube feet → can be used for sensory, movement, and feeding purposes + finding mates

• Starfish use tube feet to pry open prey!

What are some key characteristics of Phylum Chordata?

• Colemates

• Bilateral

• DUETEROSOMES

• SEGMENTED

Includes Tunicates/ Sea Squirts (Urochordata), lancelets (cephalochordata), and VERTEBRATES

How do animals under the phylum chordata grow? Do they molt?

ALL grow simply through biomass increase (gaining weight), which means NO MOLTING → no exoskeleton constraining body size

Do organisms under the phylum Chordata have an exoskeleton or an endoskeleton?

ALL have ENDOSKELETONS (internal)

What are the four KEY traits of chordates?

1. NOTOCHORD

2. DORSAL HOLLOW NERVE TUBE

3. PHARYNGEAL GILL SLITS

4. POSTANAL TAIL

What is a NOTOCHORD?

It is a stiff, yet flexible rod within the chordate’s body = beginnings of a spinal cord

What is a DORSAL HOLLOW NERVE TUBE?

It is a structure within a chordate that is the start of the central nervous system

What are PHARYNGEAL GILL SLITS associated with?

They are associated with respiration! You had them as an embryo

What is POSTANAL TAIL?

It is a muscular structure found in all chordates. It is important for movement

What are the shared traits between Tunicates/Sea Squirts, and Lancelets?

BOTH are filter/suspension feeders that pump water through filtering structures to collect organic matter particles for nutrients and energy

• They are also both found in marine environments!

Are tunicates/sea squirts mobile as adults?

NO!! They are not, they are mobile as larvae, but not as adaults

Are lancelets mobile as adults?

YES!! They are mobile as both larvae and adults

What traits DEFINE vertebrates?

They all have a…

• CRANIUM

• VERTEBRAL COLLUM

• and the ability to duplicate of hox genes and neural crest cells

What is a cranium?

It is a protective covering for the brain and sensory systems (skull in humans)

What is a vertebral column?

A structure/support for the muscles/body (allows for changes in posture/movement); also protects the nervous system

What are hox genes and neural crest cells, and why are they important?

They are developmental traits that allow for complex body plans/forms and new types of movement

Who were the earliest vertebrates?

FISH - specifically jawless fish, then jaws evolved, then bony tissue, and finally amniotic eggs

What class includes jawless fishes, include lampreys and hagfish

One of the earliest, Class Agnatha

Why was BONE important as a stage of evolution in vertebrates?

Unlike the previous usage of cartilage, bone increases skeletal support, increases strength, and allows for repair (bone can repair, cartilage cannot)

What class includes boney fishes?

Class Osteichthyes

Remember, oste(o) is the formal term for bone!!

What class of vertebrates did LIFE ON LAND evolve from

Class Amphibians

They live in both aquatic and terrestrial habiats

What are some key characteristics of Class Amphibians?

• They breathe through their skin

• REQUIRE MOISTURE in their habitats for homeostasis and breathing

• Have non-amniotic egss = requires water

What are some animals that fall under the class amphibians?

Includes frogs, toads, salamanders, and newts!

All remaining vertebrates after class amphibians have what evolved trait…

They all have AMNIOTIC EGGS = lots of embryo protection

What vertebrates have amniotic eggs?

Reptiles, birds, and mammals all have this

What are some characteristics of reptiles?

• Strict ectotherms – rely on external sources for body heat

• Specialized skin layer known as the stratum corneum (scales)

What are some key characteristics of birds?

• Have feathers and hollow bones for flight

• Endothermic = produce their own body heat

What are some key characteristics of Mammals?

• HAIR and LACTATION set them apart

• Endothermic - produce their own body heat