Intro to vertebrates

Question 1

What are some differences between the adaptations of early vertebrates and the protochordates?

Answer 1

larger size, higher activity level, higher metabolic rate

Question 2

What are the main adaptations (characteristics) of vertebrates?

Answer 2

endoskeleton (cartilage but later bone), cranium for brain protection, and vertebrae. Centra replace notochord for strength, and neural spines provide more areas for muscle attachment.

Question 3

Of the select vertebrates that develop an exoskeleton (from the skin), what are the two main types?

Answer 3

exoskeleton made of bones, exoskeleton made of keratin

Question 4

Describe the vertebrates who had an exoskeleton made of bone.

Answer 4

These were fish that created bony dermal armor that were later modified into scales.

Question 5

Describe the vertebrates who had an exoskeleton made of keratin.

Answer 5

Terrestrial vertebrates that developed keratinized dermal structures (scales, hair, feather, nails, claws)

Question 6

How was the respiratory system of early vertebrates modified to support their higher activity level?

Answer 6

vascularized gills shifts the function of the pharynx to gas exchange, muscular pharynx pumps water

Question 7

How was the circulatory system modified to support their higher activity level?

Answer 7

Developed a multichambered heart and erythrocytes with hemoglobin for enhanced transport of gas and other substances.

Question 8

How was the digestive system modified to support higher activity levels?

Answer 8

movement of food in digestive tract via muscles rather than cilia, development of accessory glands such as the liver and pancreas

Question 9

How was the excretory system modified to support their higher activity levels?

Answer 9

Kidneys were develop to remove waste and regulate body fluid/ion concentrations

Question 10

How was the nervous system modified in early vertebrates?

Answer 10

Development of distinct head, face, and special sense organs

Question 11

How was the anterior end of the nerve chord modified?

Answer 11

Enlarged to form tripartite brain protected by the cranium (forebrain, midbrain, hindbrain)

Question 12

What happened to the remainder of the nerve chord?

Answer 12

Develops into the spinal chord

Question 13

What embryonic innovations resulted in the modifications to the nervous systems of vertebrates?

Answer 13

neural crest and ectodermal placodes

Question 14

What is the main role of Hox genes?

Answer 14

development of animal body plans and patterning of body axis.

Question 15

How many hox genes do invertebrates have?

Answer 15

1 set

Question 16

How many hox genes do gnathostomes have?

Answer 16

4 sets