4. Into what cavity does the blastopore open? The gastrular slit? What becomes of each? 5. Explain the eccentric position of the early frog blastocoel. 6. Explain the changes in size and position of the frog blastocoel during gastrulation.

An infant born at term to 27-year-old woman is brought to the neonatology clinic because of urine discharge from the umbilicus that irritates the surrounding skin. Which of the following is the most likely cause of this patient's symptoms? A. Persistent yolk sac B. Persistent allantois remnant C. Omphalocele D. Hypospadia E. Gastroschisis

What critical developmental process/es are altered following retinoic acid-exposure, which may cause protrusion of the spinal cord through the vertebral arches? Select one or more: O A. Primary neurulation, where the neural plate creases inward until the edges come in contact and fuse. O B. Secondary neurulation, where the tube forms by hollowing out of the interior of a solid precursor. O C. Regulation of neural crest migration from the neural tube to generate segmental ganglia. O D. Abnormal somite formation affecting the development of muscles of the back.

7. The human female reproductive system is represented below. What structure represents the site of embryonic development? * A A В O D

1. Name and describe the four components of an unhatched blastocyst. 2. List two organs or systems that develop from each of the following germ cell layers of an embryo.. • Endoderm Mesoderm Ectoderm 3. Explain how maternal recognition of pregnancy is accomplished in pigs. 4. Explain how parturition is initiated.

1.  State the function of the following parts of the genus Romalea (grasshopper): antenna, tympanum, spiracles, ovipositor (female), gastric caeca, malphigian tubules, tracheae, air sacs    What are the hairlike appendages called that anchor into the skin of annelids? What structures do earthworms have to help dispose of nitrogenous wastes? Briefly describe how earthworms reproduce and what structures are involved.

13. ID the blue region at the white

1. What causes the light pink to bright red coloraion of most adult flamingos? 2. Please describe the eating apparatus of flamingos.  3. Why does only one nestling of Suliformes survive when 2-3 eggs are layed? 4. Wat do members of Suliformes do to incubate their eggs since they don't have brood patches?

In frogs, yolks are plugged into the bottom of the blastopore, which develops into the anus. How about in sea urchins? I know in sea urchins the blastopore will become an anus but is there also a yolk plug, or does the bottom of the archentron simply develop into the anus?

Suppose we isolate one blastomere from a 4-cell stage sea urchin embryo. What do you think will happen to the isolated blastomere? and What do you think will happen to the now 3-celled embryo?