Embryology I

Question 1

What does the metencephalon become?

Answer 1

• the brain stem
• pons
• cerebellum
• 4th ventricle

Question 2

Where does neural cell proliferation occur?

Answer 2

in the ventricular zones (near the lumen of the neural tube)

Question 3

In the telecephalon, the gray matter is located ____.

Answer 3

on the outside

Question 4

The notocord will eventually develop into the _____.

Answer 4

nucleus pulposus

Question 5

The neural progenitors of the spinal cord closest to the ventral aspect of the neural tube will develop into _____.

Answer 5

motor neurons

Question 6

The _____ will eventually develop into the nucleus pulposus.

Answer 6

notocord

Question 7

What is the cephalic flexure?

Answer 7

the bend btw the brain and brainstem/diecephalon and mesencephalon

Question 8

How many segments does the prosencephalic vescicle form into?

Answer 8

3

Question 9

The ____ plate becomes the afferent side of the spinal tract.

Answer 9

alar

Question 10

A signal from the implanting trophoblast induces a “head organizer” that generates factor _____.

Answer 10

Cerebrus

Question 11

Above the cephalic flexure, the dorsal direction is towards the top of the head, while below it, the dorsal direction is ______.

Answer 11

towards the back

Question 12

How does sonic hedgehog (Shh) influence neurulation?

Answer 12

it induces the overlying ectoderm to divide, creating the neural plate

Question 13

The caudal cell mass at day 28-32 ultimately gives rise to the ____ and ____.

Answer 13

• conus medullaris
• filum terminale

Question 14

____ genes play a fundamental role in the AP patterning of nervous tissue.

Answer 14

Homeobox

Question 15

Above the cephalic flexure, the dorsal direction is ______, while below it, the dorsal direction is towards the back.

Answer 15

towards the top of the head

Question 16

What does the sulcus limitans do?

Answer 16

separates the ventral population from the dorsal population in the neural tube

Question 17

How many rhombomeres are there?

Answer 17

8

Question 18

From which embryological structure do the cerebral hemispheres and lateral ventricles all arise?

Answer 18

the telecephalon

Question 19

In the forebrain, the neural tube will develop into what 3 discrete proliferative zones?

Answer 19

1. cortex (dorsal)
2. ganglionic eminences (medial and lateral)
3. basal forebrain (ventral)

Question 20

In the spinal cord, the gray matter is located ____.

Answer 20

on the inside

Question 21

The _____ plate becomes the efferent side of the spinal tract.

Answer 21

basal

Question 22

How many cell layers make up the cerebral cortex?

Answer 22

6

Question 23

The basal plate becomes the ______ side of the spinal tract.

Answer 23

efferent

Question 24

For patterning along the AP(RC) axis, the principal morphogens appear to be ____, ____, and _____.

Answer 24

• Wnts
• FGFs
• Retinoic Acid (RA)

Question 25

Hox genes cause the development of \_\_\_\_\_.

Answer 25

the 8 rhombomeres

Question 26

What axis does an entering sperm into an egg create?

Answer 26

the embryonic/abembryonic axis

Question 27

\_\_\_ genes cause the development of the 8 rhombomeres.

Answer 27

Hox

Question 28

Hox gene expression varies according to position along the \_\_\_\_\_.

Answer 28

AP axis

Question 29

Above the \_\_\_\_\_\_, the dorsal direction is towards the top of the head, while below it, the dorsal direction is towards the back.

Answer 29

cephalic flexure

Question 30

The alar plate becomes the ______ side of the spinal tract.

Answer 30

afferent

Question 31

The edge that leads implantation will become the ____ end of the embryo.

Answer 31

caudal

Question 32

From which embryological structure do the the brain stem, pons, cerebellum, and 4th ventricle all arise?

Answer 32

the metencephalon

Question 33

On what side of the blastocyst does implantation occur?

Answer 33

the ICM side

Question 34

What does the myelencephalon become?

Answer 34

* the brain stem * medulla oblongata * 4th ventricle

Question 35

What signaling molecule does the notocord release?

Answer 35

sonic hedgehog (Shh)

Question 36

What does the mesecephalon become?

Answer 36

* the brain stem * midbrain * cerebral aqueduct

Question 37

What does the dorsal population of neural tube cells become?

Answer 37

the alar plate

Question 38

What is the first event that establishes symmetry in the mammalian egg?

Answer 38

sperm entry

Question 39

The gray matter regions will become either the ____ plate or the _____ plate.

Answer 39

basal; alar

Question 40

From which embryological structure do the brain stem, medulla oblongata, and 4th ventricle all arise?

Answer 40

the myelencephalon

Question 41

The fiber pathway that splits the ganglionic eminence is the \_\_\_\_\_.

Answer 41

internal capsule

Question 42

What causes dorsoventral patterning in the forebrain?

Answer 42

* morphogen gradients * regional gene transcription changes

Question 43

What does the ventral population of neural tube cells become?

Answer 43

the basal plate

Question 44

From which embryological structure do the thalamus, hypothalamus, epithalamus, and third ventricle all arise?

Answer 44

the diencephalon

Question 45

From which embryological structure do the brain stem, midbrain, and cerebral aqueduct all arise?

Answer 45

the mesecephalon

Question 46

What are the components of the basal ganglia?

Answer 46

* putamen * globus pallidus * caudate nucleus

Question 47

During cell migration in the telencephalon, each successive migration forms a more ______ layer of cells.

Answer 47

superficial

Question 48

The neural progenitors of the spinal cord develop into distinct populations based on \_\_\_\_\_.

Answer 48

their position along the dorsal-ventral (DV) axis

Question 49

Excess _____ causes an excess of posterior structures and is a powerful teratogen.

Answer 49

Retinoic Acid (RA)

Question 50

What does the diencephalon become?

Answer 50

* the thalamus * hypothalamus * epithalamus * third ventricle

Question 51

What does the endoderm form?

Answer 51

the lining of the gut

Question 52

How many segments does the mesencephalic vescicle form into?

Answer 52

none

Question 53

What is the crease in the neural tube called?

Answer 53

the sulcus limitans

Question 54

What is the sulcus limitans?

Answer 54

the crease in the neural tube

Question 55

The cells making up the walls of the neural tube become ____ and ____ cells.

Answer 55

neurons; glial

Question 56

How are the lateral ventricles connected?

Answer 56

they're not- they connect to the 3rd ventricle

Question 57

What does the telencephalon become?

Answer 57

* the cerebral hemispheres * lateral ventricles

Question 58

How many segments does the rhombencephalic vescicle form into?

Answer 58

2