Lesson 24a (the Chordates p1)

Question 1

What is phylum Chordata?

Answer 1

The Chordates

Question 2

What are 4 characteristics of Chordates?

Answer 2

A. Pharyngeal slits

 1. Connect the inside of the throat to the outside of the neck
 2. Develop into gills in aquatic animals
 3. Only present during embryonic development in terrestrial animals

B. Dorsal hollow nerve cord

 1. A bundle of nerve fibers running down the back
 2. Nerve cord is derived from the ectoderm in early development
 3. Main function is to connect the brain with the muscles and other organs

C. Notochord

1. Rod-shaped structure that provides skeletal support
2. Typically develops into a backbone

D. Post-anal tail

1. An extension of the body past the anal opening
2. Lost very early in human development

Question 3

What is subphylum Urochordata (phylum chordata)

6 characteristics

Answer 3

The Tunicates

1. Have a nerve cord, notochord, and post-anal tail only during the larval stage
2. Marine animals found in shallow waters
3. Sessile as adults
4. Hatch from eggs, and then attach to the ocean floor
5. Undergo metamorphosis as they mature, and lose their nerve cord, notochord, and tail
6. Filter feeders that primarily eat plankton

https: //st2.depositphotos.com/1729435/8198/i/450/depositphotos_81982352-stock-photo-purple-tunicates.jpg
file: ///C:/Users/trgan/Sync/LisA%20school/Tunicets.png

Question 4

What is subphylum Cephalochordata?

Answer 4

The Lancelets

1. Do not have a backbone or brain
2. Found primarily in tropical marine waters
3. Keep their nerve cord, tail, pharyngeal slits, and notochord into adulthood
4. Notochord does not develop into a backbone

file: ///C:/Users/trgan/Sync/LisA%20school/Lancalet.png
https: //thumbs.dreamstime.com/b/amphioxus-lancelets-also-known-as-amphioxi-comprise-some-thirty-two-species-fish-like-marine-chordates-global-46788088.jpg

Question 5

What is subphylum Vertebrata?

What are its 7 classes?

Answer 5

The Vertebrates

Seven Classes

a) Class Agnatha: jawless fish
b) Class Chondrichthyes: cartilaginous fish
c) Class Osteichthyes: bony fish
d) ClassAmphibia:amphibians
e) Class Reptilia: reptiles
f) Class Aves: birds
g) Class Mammalia: mammals

Question 6

What are 6 characteristics of vertebrates?

Answer 6

a) Vertebral column: backbone with a hollow tube of nervous tissue, known as the spinal cord
b) Gastrointestinal tract: includes mouth at the anterior end of the animal and an anus at the posterior end
c) Endoskeleton: an internal frame made of bone or cartilage that provides support for the body
d) Closed circulatory system: blood cells stay closed inside of blood vessels
e) Sexual reproduction: males have testes that produce sperm and females have ovaries that produce eggs

f) Complex nervous system
(1) Brain segmented into lobes
(2) Brain sends and receives signals from the body via the
spinal cord
(3) Spinal cord with many spinal nerves to send and receive
signals all over the body