Lec Exam (updated)

What symmetry type do Echinoderm larvae have?

Bilateral

What symmetry type do Echinoderm adults have?

Pentaradial 

How many tissue layers do Echinoderms have?

Three (3)

What body cavity do Echinoderms and Invert Chordates have?

Coelomate

Are Echinoderms protostomes or deuterostomes?

Deuterostomes

Echinoderms are part of which superphylum? 

Neither

What sexes do Echinoderms have?

Both hermaphrodites and separate sexes

How do Echinoderms exchange gases and waste?

Diffusion across their body surface. 

Can Echinoderms reproduce asexually? And how?

Yes, via fragmentation.

The nervous system of Echinoderms consists of…

• Nerve ring around mouth

• Radial nerves 

Echinoderms’ system for moving and holding food is…

Water vascular system 

Name meaning of Ophiuroidea?

“Snake-tail skin”

What is different about tube feet in Ophiuroidea (brittle stars) ?

They are reduced.

The holes on tube feet are…

Dermal gills

Fused ossicles form a…

Test

Name meaning of Holothuroidea?

“Sea cucumber”

What is different about ossicles in sea cucumbers?

They are not fused, so the body is soft.

What external characters in Holothuroidea show they are Echinoderms? 

• Pentaradial symmetry

• Tube feet

What internal characters in Holothuroidea show they are Echinoderms? 

• Water vascular system

• Reduced ossicle skeleton

Besides using skin and tube feet, how do Holothuroidea exchange gases?

Cloacal respiration via the anus to respiratory trees.

Holothuroidea eat using which parts?

Both

Name meaning of Echinoidea?

“Spiny”

Features of ambulacral plates on an urchin?

Tube feet, and holes

Features of interambulacral plates on an urchin?

Spines, no holes

Urchins are mostly herbivorous. 

True

Pedicellaria are used for…

Defense

What does A represent?

Madreporite

Which labels are correct? 

A. Ambulacral groove B. Mouth C. Tube feet 

What special way does Asteroidea eat?

Everting the cardiac stomach to digest food.

What symmetry type do Invert Chordates have?

Bilateral

Invert Chordates have a complete digestive tract.

True

Are Chordates protostomes or deuterostomes?

Deuterostomes 

The subphylum that includes tunicates and salps?

Urochordata

The subphylum that includes lancelets?

Cephalocordata

What are the 5 characters that unite all chordates?

Post-anal tail

Pharyngeal slits

Notochord

Dorsal, hollow nerve cord

Endostyle 

How do lancelets feed?

They create a current to their mouth to the pharyngeal slits, where food is caught in the slits, with mucus produced by the endostyle.

Pharyngeal pouches open to the outside.

False

What is the function of the endostyle?

It creates mucus to coat the pharyngeal slits, so they can catch food.

Which directs the formation of the dorsal, hollow nerve cord?

Notochord

In what habitats are lancelets found?

They are buried in sand, in warm / tropical seas.

What sexes do Lancelets have?

Only separate sexes

What is the pathway of water through lancelets?

Water enters from the mouth and exits through the atriopore. 

Which chordate characters of tunicate larva remain after metamorphosis into adults?

The pharyngeal slits and endostyle. 

What unusual material is the tunic made of?

Cellulose 

Label the diagram.

A. dorsal, hollow nerve cord B. notochord C. post-anal tail D. cirri E. pharyngeal slits F. atrium G. intestine H. atriopore I. anus

Label the diagram.

A. dorsal fin B. dorsal, hollow nerve cord C. notochord D. hepatic cecum E. gonad F. pharyngeal slits G. endostyle

Label the diagram.

A. oral siphon B. atrial siphon C. dorsal, hollow nerve cord D. post-anal tail E. pharyngeal basket F. stomach G. notochord 

Label the diagram.

A. oral siphon B. pharyngeal basket C. tunic D. atrial siphon E. heart F. stomach 

The vast majority of tunicates are hermaphrodites.

True

In the water vascular system…

Water provides pressure.

The other side of the tube foot, inside the star is attached to…

Ampulla

In echinoderms, the endoskeleton is made of…

Ossicles (made of calcium carbonate)

Both sea stars and urchins have which structure? 

Pedicellaria 

Where are gonads found in sea stars?

The arms

Vertebrata is distinguished by which two traits?

Cranium and vertebrae

Urochordates are ________ and Cephalocordates (which includes lancelets) are __________. 

Hermaphrodites, separate sexes 

What is the function of the hepatic cecum?

Aiding digestion with enzymes.

In tunicates, the anus extends all the way through the atrial siphon.

False

What is the function of the madreporite?

It allows water to enter the the water vascular system.

Lancelets (Cephalocordates) have all 5 chordate features (including endostyle) as both larvae and adults.

True

The vertebrae in hagfish (Myxini) is…

Greatly reduced.

Many lampreys (Petromyzontida) are _________, meaning they latch onto the outside.

Ectoparasitic

Both hagfish and lampreys have scales, jaws, and paired fins.

False

Both hagfish and lampreys have which structure?

Horned tongue with projections

How many chambers do amphibian hearts have?

3

How many ventricles do amphibian hearts have?

1

How many atria do amphibian hearts have?

2

Amphibians breath in via ________ pressure. 

Positive (Force air into the lungs to inflate them)

Which is the largest vein attached to the right atria?

Vena cava 

Systemic circulation:

Heart, body

Pulmocutaneous circulation:

Heart, skin, lungs 

How many cervical vertebrae do amphibians have?

1, atlas (only up and down movement)

Amphibians have ribcages.

False

Terrestrial amphibian adults excrete:

Urea 

Aquatic amphibian larvae excrete:

Ammonia 

What is the function of vomerine teeth?

Holding prey to prevent it from escaping, so the frog can swallow it.  

Which mouth feature leads to the lungs?

Glottis 

What is unusual about frog lungs?

They are hollow.

The pancreas produces …

Enzymes, for digestion

The urinary bladder & large intestine ends at the…

Cloaca

Which organ produces bile?

Liver

Which organ stores bile?

Gallbladder

What are hurdles of terrestrial environments? 

• Drastic temperature variation

• Solar radiation

• No buoyancy

• Dessication

What are positives of terrestrial environments? 

• 20x more oxygen in air

• Varied habitats

• Unexploited food source

• No big predators (yet)

What chordate features do Myxini & Petromyzontida have as embryos?

Post-anal tail  Pharyngeal pouch Notochord Dorsal, hollow nerve cord Thyroid gland 

What are some adaptations for living on land?

• Complex lungs

• Limbs to support body weight

• Sense organs to detect airborne sounds / movement (ears, nostrils)

How does the amniotic egg link mammals to reptile ancestors?

It is a structure from when common reptile ancestors laid eggs.

Which is true about Gorgonopsid teeth? 

All of the above

Which describes heterodont teeth?

• specialized shapes

• for chewing

• not replaceable

Which describes homodont teeth?

• repeating conical, peg shapes 

• for biting 

• replaceable 

Why do we think Thrinaxodon may have had hair or similar structures?

• Pits on the skull that suggest whiskers

• To help with navigating burrows and darkness

What is one similarity between mammal and reptile skin?

Both have dead skin layers to prevent desiccation.

What is one difference between mammal and reptile skin?

Both are true.

What is the function of the EDA gene?

Both are true. 

How many ear bones do reptiles have?

1, the stapes

How many ear bones do mammals have?

3, the stapes, incus and malleus

How did the jaw bones become ear bones?

Jaw joints, first located in the back of the jaw, turned into the incus and malleus. 

Why did Hadrocodium develop a large brain?

They needed a large brain to process their surroundings in the dark, to avoid dinosaurs

Label the diagram.

A. liver B. heart C. fat bodies 

Label the diagram.

D. small intestine E. stomach F. urinary bladder