Chapter 2: Vertebrate Relationships And Basic Structure

Question 1

True or False

Chordates are basically bilaterally symmetrical animals?

Answer 1

True

One side is the mirror image of the other

Question 2

How is the phylum Chordata related to the phylum Echinodermata (starfish, sea urchins)?

Answer 2

They are marine forms without distinct heads and have pentaradial symmetry (fivefold and circular)

Question 3

What are the 5 characteristics of Chordates?

Answer 3

1) Notochord
2) Dorsal, hollow nerve cord
3) Thyroid gland
4) Post-anal tail
5) Pharyngeal gill slits

Question 4

What are two main groups of Non-vertebrate Chordates?

Answer 4

Tunicates (Urochordates)

Lancelets (Cephalochordate)

Question 5

What are Tunicates?

Answer 5

Marine animals that filter particles of food from the water with a basket-like perforated pharynx

Question 6

What is another name for Tunicates?

Answer 6

Sea squirts

Question 7

True or False

Tunicates are very similar to Cephalochordates and vertebrates

Answer 7

FALSE

They bear little symmetry. The only reason they belong to the phylum Chordata is because of their tadpole-like, free-swimming larvae

Question 8

Why are Lancelets commonly known as “amphioxus”?

Answer 8

Amphioxus means “sharp at both ends”.

Lancelets are animals where front and rear ends have the same shape but lack a distinct head

Question 9

Name some characteristics of vertebrates.

Answer 9

• cranium, skull, which surrounds the brain
• prominent head with complex sense organs
• spinal column (backbone)

Question 10

What is the Hox gene complex?

Answer 10

Sequence of DNA that regulates the expression of genes that control development of body structures.

It’s important in early development (where is the head and tail)

Question 11

True or False

Vertebrates are smaller than non-vertebrate chordates

Answer 11

FALSE

They are much larger and are also more active and have more mobility

Question 12

What does embryology help do?

Answer 12

By studying embryos, it can show how systems developed and and how complex structures are formed.
It can also provide clues about the ancestral condition and about homologies between structures in different animals.

Question 13

Name the 5 tissue types in vertebrates

Answer 13

1) epithelial
2) connective
3) vascular (blood)
4) muscular
5) nervous

Question 14

Tissues are combined to form…?

Answer 14

Organs

Question 15

What is collagen?

Answer 15

A fibrous protein in most animal tissues

Question 16

What is keratin?

Answer 16

A fibrous protein mainly found in the epidermis (outer skin) that makes structured such as hair, scales, feathers, claws, horns, beaks, etc.

Question 17

True or false

Chordates do not have a brain

Answer 17

FALSE

All Chordates have some form of a brain, as a thickening of the front end of the notochord

Question 18

What kind of brain do all vertebrates have?

Answer 18

Tripartite (three-part)

Question 19

What is the pineal organ?

Answer 19

Also known as the third eye. It helps detect day from night

Question 20

What is an important structural tissue in vertebrates and many invertebrates?

Answer 20

Cartilage

Question 21

Bone is composed of what types of cells?

Answer 21

Osteocytes

Question 22

What are the 2 main types of bones in vertebrates?

Answer 22

Dermal bone (formed in the skin)
Endochondral bone (formed inside cartilage)