Chapter 3 Vertebrates-Section 1

Question 1

What are the three characteristics of chordates?

Answer 1

At some point in their lives, chordates will have a notochord, a nerve cord that runs down their back, and slits in their throat area.

Question 2

What are some examples of chordates?

Answer 2

Fishes, amphibians, reptiles, birds, and mammals.

Question 3

Are all chordates vertebrates?

Answer 3

No, a few chordates are invertebrates.

Question 4

What is a flexible rod that supports a chordates back called?

Answer 4

Notochord

Question 5

In vertebrates, part or all of the notochord is replaced by what?

Answer 5

A backbone

Question 6

What does the nerve cord that runs down your back do? And what is it called?

Answer 6

The nerve cord is the connection between the brain and the nerves. In humans, it is called a spinal cord.

Question 7

What are slits in the throat area called?

Answer 7

Pharyngeal slits, or gill slits.

Question 8

Do all chordates keep their gill slits for their entire life?

Answer 8

Some chordates, like fishes, keep their slits as part of their gills for their entire life. But in many vertebrates, including humans, pharyngeal slits disappear before birth.

Question 9

What are two characteristics of vertebrates?

Answer 9

A vertebrate has a backbone that is part of an internal skeleton.

Question 10

What is another name for a vertebrate’s backbone? And how is the backbone formed?

Answer 10

A vertebrate’s backbone is also called a spine. The backbone is formed by many similar bones called vertebrae. The vertebrae are lined up in a row like beads on a string. Each vertebrae has a hole in it that allows the spinal cord to pass through it.

Question 11

What is another word for internal skeleton? And what is the function of the internal skeleton?

Answer 11

Endoskeleton. The endoskeleton protects the internal organs of the body, helps give the body shape, and gives muscles a place to attach.

Question 12

What are the three things included in a vertebrate’s endoskeleton?

Answer 12

Backbone, skull, and ribs.

Question 13

What do the skull and ribs protect?

Answer 13

The skull protects the brain. The ribs attached to the vertebrae and protect the heart, lungs, and other internal organs.

Question 14

Does a vertebrate’s endoskeleton need to be replaced as the animal grows, like an arthropod exoskeleton?

Answer 14

No

Question 15

True or false

Vertebrates can grow bigger than animals with exoskeletons or no skeletons at all.

Answer 15

True

Question 16

What is one characteristic that differs among the major groups of vertebrates?

Answer 16

The way they control their body temperature.

Question 17

What is the body temperature of most fishes, amphibians, and reptiles?

Answer 17

Their body temperature is close to the temperature of their environment.

Question 18

What is an animal called whose body does not produce much internal heat?

Answer 18

Ectotherm

Question 19

What are ectotherms sometimes called? And what are three examples of ectotherms?

Answer 19

Ectotherms are sometimes called cold-blooded. Fishes, amphibians, reptiles are all ectotherms. For example when a turtle is lying on a sunny river bank, it has a higher body temperature than when it is swimming in a cool river.

Question 20

What is an animal called whose body regulates it’s own temperature by controlling the internal heat it produces? Give an example.

Answer 20

Endotherm. Birds and mammals. For example, a beaver would have the same body temperature whether it is in cool water or on warm land.

Question 21

Endotherm’s also have other adaptations. List two and give examples.

Answer 21

Sweat glands and fur or feathers. When endotherms sweat, the sweat evaporates, and the animal is cooled. Fur or feathers keep in the endotherms warm.

Question 22

True or false

Because endotherms can keep their body temperature stable, they are limited as to what environment they can live in.

Answer 22

False. Because endotherms can keep their body temperature stable, they can live in a greater variety of environments than ectotherms can.