Embryology

Sample Exam #2

Multiple Choice (2 pts each)

1. Failure to close the neural tube at the site of the future spinal cord could cause:

a) spina bifida b) microencephaly c) hydrocephaly d) anencephaly

2. Neurons which have their cell bodies within ganglia (PNS) develop from:

a) neural crest cells b) neuroglia (glial cells)

c) neuroblasts within the neural tube d) notochordal cells

3. Sensory neurons of the Peripheral Nervous System (PNS):

a) send information away from the CNS

b) have cell bodies in the neural tube

c) develop from neural crest cells

d) all of the above

4.The function of the choroid plexus is to:

a) transmit impulses between the two cerebral hemispheres

b) produce cerebrospinal fluid

c) pump blood through the ventricles

d) allow for vision

5. In comparison to lower vertebrates, the most developed region of the human brain (greatest number of neurons) is the:

a) diencephalon b) telencephalon

c) mesencephalon d) myelencephalon

e) metencephalon

6. Predict the results from the following experiment.

The notochord's position is reversed (cranial to caudal position) below the neural plate.

a) the neural tube will not form

b) the rhombencephalon will be at the anterior end of the embryo

c) spina bifida will occur

d) an atrial septal defect will occur

7. The prosencephalon produces the:

a) telencephalon & diencephalon

b) metencephalon & myelencephalon

c) mesencephalon & metencephalon

d) metencephalon & diencephalon

8. Lens induction is due to the presence of the:

a) telencephalon b) optic cup c) notochordal mesoderm d) endoderm of the foregut

9. The sinus venosus will become part of the adult:

a) left ventricle b) right ventricle c) right atrium d) left atrium

10. Which of the following connects the ventral aorta (aortic sac) with the dorsal aortae?

a) bulbus cordis b) branchial arches c) aortic arches d) common cardinals e) forman ovale

11. The pulmonary arteries and ductus arteriosus develop from the ____ aortic arch.

a) 4th b) 5th c) 3rd d) 1st e) 6th f) 8th

12. Increased blood flow through an embryonic blood vessel, endothelial tube, will result in:

a) no change in the blood vessel

b) degeneration of the blood vessel

c) formation of an artery or vein

d) degeneration of angioblasts

13. The aorta in mammals develops from the:

a) common cardinal b) right third aortic arch

c) left fourth aortic arch d) first aortic arch

14. The function of the allantois is to:

a) store nutrients for the embryo b) provide gas exchange for the fetus

c) store uric acid d) produce fluid to buffer shock

15. Which of the following statements concerning extraembryonic membranes is correct?

a) The amnion develops from the somatopleure (epi. ecto and somatic mesoderm)

b) The yolk sac is the site of most nutrition for the mammalian embryo

c) The placenta produces fluid to buffer shock in the bird embryo

d) The yolk sac forms from the somatic mesoderm and the endoderm

Matching

(11 pts) 16. Match the following regions in the adult brain with the embryonic structures from which they develop. ( more than one answer for each embryonic structure is possible)

EMBRYONIC ADULT

a. telencephalon 1.) pons 2) cerebrum 3) cerebellum

b. diencephalon 4) pineal gland 5) optic nerve and retina

c. mesencephalon 6) thalamus 7) posterior pituitary

d. metencephalon 8) medulla oblongata 9) midbrain

e. myelencephalon 10) olfactory nerve 11) hypothalamus

 

(5 pts) 17.Label the drawing with the following embryonic veins:

anterior cardinals, common cardinals, posterior cardinals, vitelline veins and umbilical veins.

Essays:

( 12 pts) 18. Predict and explain the results from the following experiment in terms of regulation of peripheral nerve growth.

The right forelimb of a frog embryo is severed and replaced with another organ (eye). The severed limb is transplanted to the left side of the embryo directly below the left forelimb.

 

 

 

 

 

 

(18pts.) 19.a) Describe the function of the following fetal structures: foramen ovale, ductus arteriosus, ductus venosus and umbilical arteries and vein.

b) Explain the changes that occur in the circulatory system at birth and describe what happens in the following congenital malformations: atrial septal defect and patent ductus arteriosus.

(12pts) 20. Describe the development of the endocardium, myocardium and pericardium of the heart. Describe the position and number of chambers during the development of the embryonic heart in humans.

 

(12 pts) 21. Contrast somatic, parasympathetic and sympathetic motor neurons.

Be sure to include: origin of cells (neural crest or neural tube), number of synapses, type of neurotransmitter(ACh or NE), type of effector (skeletal muscle, or smooth/cardiac/glands)