Question

25-28

23. A vertebra with a dens. D. crocodile 24. A skull with an eye opening, nasal openings, and a single occipital 2 E. typical lizard condyle, but no other lateral skull openings. Egg Features 25. The outer covering of a reptile egg. 26. Feature marked on diagram by a. 27. Stores nitrogenous (excretory) waste A. Amnion B. Allantois. C. Chorion. D. Yolk sac and is the primary site of respiratory gas exchange 28. The kind of egg shown here is found: A. Only in Amphibia. B. Only in Amphibia and Reptilia. C. Only in Reptilia. D. Only in Reptilia and Aves. E. Only in Reptilia, Aves, and some Mammalia. F. In all Tetrapods. Changes In Vertebrate Features: At what point in vertebrate phylogeny did each of the following features first appear. 29. Water removed from urine after it enters the bladder and cloaca 20 Internal fertilization.

Answer 1

EGG FEATURES

Question 25.

Answer is C) Chorion

The Chorion is responsible for air exchange between the egg and the external environment and surrounds the embryo and the yolk sac. The other choices, A) Amnion protects the embryo from shock; B) Allantois stores nitrogenous wastes, and D) Yolk sac provides necessary nutrients.

Question 26.

Answer is Amnion which surrounds the embryo and carries amniotic fluid.

Question 27.

Answer is Allantois which is responsible for storing the nitrogenous wastes of the embryo as well as facilitating the respiration process.

Question 28.

Answer is E) Only in reptiles, Aves and some mammals

The figure shown is an example of an amniotic egg which are different than amphibian eggs due to the presence of amniotic membranes. The egg of reptiles look leathery and require moisture, egg of birds are made of calcium carbonate and are quite brittle and hard, and most mammals don't lay eggs with an exception of monotremes, but the amniotic membrane is present within the body of the female mammal.