1A Foundations 1 - Embryology

Question 1

Sperm + Oocyte = ?

Answer 1

Zygote

Question 2

Next step after zygote?

Answer 2

Morula (meaning = Mulberry)

Question 3

Next step after morula?

Answer 3

Blastocyst

Question 4

Parts of a blastocyst?

Answer 4

Trophoblast + Inner cell mass

Question 5

On what day does implantation into the endometrium happen happen?

Answer 5

Day 6

Question 6

What does the trophoblast turn into (finally)?

Answer 6

Placenta

Question 7

What does the inner cell mass turn into (finally)?

Answer 7

Fetus

Question 8

What does the trophoblast turn into?

Answer 8

Cytotrophoblast

Syncytiotrophoblast

Question 9

What does the Syncytiotrophoblast make?

Answer 9

hCG. This hormone tell the corpus luteum that a successful implantation has taken place and thus prevents menstruation.

Question 10

What does the Cytotrophoblast make?

Answer 10

Cells

Question 11

What does the corpus luteum secrete? And what is the effect?

Answer 11

Progesterone.

Maintains endometrial lining and thus prevents menstruation

Question 12

The next step after formation of cytotrophoblasts and syncytiotrophoblasts?

Answer 12

Formation of Chorion with villi (that grows into the maternal part of the placenta)

Question 13

What structure does the Chorion with villi make up?

Answer 13

Fetal part of the placenta

Question 14

What is the name of the maternal component of the placenta and what is it made up of?

Answer 14

Decidua basalis.

Endometrium

Question 15

When is the embryonic phase?

Answer 15

Between week three and eight

Question 16

What is neurulation?

Answer 16

Formation of a neural tube

Question 17

When are the three germ layers produced?

Answer 17

At the end of the third week

Question 18

Where is the notochord? And what does it give rise to?

Answer 18

Mesoderm.

Gives rise to overlying ectoderm to differentiate into neural plate

Question 19

What does the neural plate give rise to? And which germ layer do they arise from?

Answer 19

Neural tube and neural crest cells. They arise from Ectoderm.

Question 20

What neural crest derivatives are found in the Peripheral nervous system?

Answer 20

Autonomic NS (Vagus nerve, Sympathetic ganglia), Dorsal root ganglia, sensory nerves, Schwann cells, Cranial nerves

Question 21

What neural crest derivatives are found in the Ear?

Answer 21

Ossicles of the middle ear (Malleus, Incus, Stapes)

Question 22

What neural crest derivatives are found in the Eye?

Answer 22

Anterior chamber (cornea, sclera, ciliary muscle, iris pigment cells)

Question 23

What neural crest derivatives are found in the Adrenal gland?

Answer 23

Chromaffin cells of the adrenal medulla

Question 24

What neural crest derivatives are found in the Mouth?

Answer 24

Odontoblasts

Question 25

What neural crest derivatives are found in the Heart?

Answer 25

Aorticopulmonary septum (spiral septum)

Question 26

What neural crest derivatives are found in the Digestive system?

Answer 26

Enteric nervous system, celiac ganglion, enterochromaffin cells

Question 27

What neural crest derivatives are found in the Thyroid?

Answer 27

Parafollicular (C) cells

Question 28

What neural crest derivatives are found in the Skin?

Answer 28

Melanocytes

Question 29

What does the neural tube become?

Answer 29

Brain and spinal cord

Question 30

What does chromaffin cells make?

Answer 30

Catecholamines: Epinephrin and norepinephrin

Question 31

What does odontoblasts give rise to?

Answer 31

Dentin of teeth

Question 32

What does enterochromaffin cells secrete?

Answer 32

Serotonin

Question 33

What does the parafollicular cells secrete?

Answer 33

Calcitonin

Question 34

What does neuroectoderm give rise to?

Answer 34

``` Neurons of brain and spinal cord Oligodendrocytes Ependymal cells Optic nerve Retina Pineal gland Post pituitary (neurohypophysis) ```

Question 35

What is the function of oligodendrocytes?

Answer 35

Myelinate the CNS neurons

Question 36

What is the function of Astrocytes?

Answer 36

Support the neurons of the CNS

Question 37

Function of Ependymal cells?

Answer 37

Secrete CSF

Question 38

Why is surface ectoderm not neurological?

Answer 38

Did not get influenced by the notochord

Question 39

What does the Surface ectoderm give rise to?

Answer 39

``` "Head structures" Lenses of the eye Olfactory epithelium Inner ear Ant. pituitary Oral epithelium Salivary glands Epidermis Sweat glands Mammary glands Anal canal distal to pectinate line ```

Question 40

What does the endoderm give rise to?

Answer 40

``` Gi tract (esophagus to pectinate line) Liver, Gallbladder, Pancreas Lungs Thymus Parathyroid glands Follicular cells of thyroid Epithelium of bladder/urethra and lower 2/3 of vagina ```

Question 41

What does the mesoderm give rise to?

Answer 41

``` Bone muscle bone marrow blood cells heart blood vessels lymphatics Upper portion of vagina Kidneys, adrenal cortex Gonads Dermis of skin ```