Chapter 47- Animal Development

Question 1

Front

Answer 1

Back

Question 2

What is a zygote and how is it formed?

Answer 2

A fertilized egg formed by the fusion of sperm and egg.

Root Word Help: zygo- = yoke/join (joining of gametes)
Mnemonic: Zygote = Zipped together genes

Question 3

In protostomes, what does the blastopore become?

Answer 3

An animal whose mouth forms from the blastopore.

Root Word Help: proto- = first, -stome = mouth
Mnemonic: Protostome = ‘Proto-mouth’ first

Question 4

In deuterostomes, what does the blastopore become?

Answer 4

An animal whose anus forms from the blastopore.

Root Word Help: deutero- = second, -stome = mouth
Mnemonic: Deuterostome = ‘Deuce first’ (anus first)

Question 5

What kind of yolk distribution does an isolecithal egg have?

Answer 5

An egg with little yolk that is evenly distributed.

Root Word Help: iso- = equal, lecith- = yolk
Mnemonic: Isolecithal = ‘Equal yolk’

Question 6

Which type of egg has a moderate yolk amount?

Answer 6

An egg with a moderate amount of yolk.

Root Word Help: meso- = middle, lecith- = yolk
Mnemonic: Mesolecithal = ‘Medium yolk’

Question 7

Which egg type has yolk concentrated at one end?

Answer 7

An egg with a large amount of yolk concentrated at one end.

Root Word Help: telo- = end, lecith- = yolk
Mnemonic: Telolecithal = ‘Yolk at the terminal end’

Question 8

What is holoblastic cleavage?

Answer 8

Complete cleavage pattern of the egg.

Root Word Help: holo- = whole, -blastic = to bud/sprout
Mnemonic: Holoblastic = ‘Whole egg splits’

Question 9

What causes meroblastic cleavage?

Answer 9

Partial cleavage pattern of the egg due to heavy yolk.

Root Word Help: mero- = part, -blastic = to bud/sprout
Mnemonic: Meroblastic = ‘Merely part of the egg divides’

Question 10

Which structures arise from the ectoderm?

Answer 10

Outer germ layer; forms skin, nervous system, sensory organs.

Root Word Help: ecto- = outside, -derm = skin/layer
Mnemonic: Ectoderm = ‘External stuff’

Question 11

Which layer gives rise to muscles and bones?

Answer 11

Middle germ layer; forms muscles, bones, circulatory system.

Root Word Help: meso- = middle, -derm = skin/layer
Mnemonic: Mesoderm = ‘Muscle in the middle’

Question 12

What structures develop from the endoderm?

Answer 12

Inner germ layer; forms gut lining, pancreas, thyroid.

Root Word Help: endo- = inside, -derm = skin/layer
Mnemonic: Endoderm = ‘Inside organs’

Question 13

What is neurulation and which germ layer is involved?

Answer 13

Process of nervous system formation from ectoderm.

Root Word Help: neur- = nerve, -ation = process
Mnemonic: Neurulation = ‘Neuro-creation’