Intro to Embryology

Question 1

What is the Cumulus Oophorus

Answer 1

A group of cells that encompass the mature ovum before and after it’s released from the follicle

Question 2

What is the location of fertilisation?

Answer 2

Ampulla of fallopian tube

Question 3

What is “Mittelshmerz”?

Answer 3

Pain during ovulation associated with a slight rise in temperature

Question 4

What is the zona pellucida?

Answer 4

Location where sperm congregate in attempt to fertilise egg

Question 5

What are the adaptations of the epithelial lining to allow for ovum to make contact with lining?

Answer 5

Extremely folded + ciliated and has goblet cells to produce mucus which allows ovum to be transported

Question 6

What part of the female reproductive tract produces eggs?

Answer 6

Ovaries

Question 7

What is a Morula?

Answer 7

Zygote once it reaches around 16 cells. This is the stage before developing the blastocoel cavity

Question 8

Why is the morula housed inside the zona pellucida?

Answer 8

Protection, so it doesn’t implant within the fallopian tubes

Question 9

What makes up the blastocyst?

Answer 9

Trophoblast (wall of blastocyst) and ICM (inner cell mass)

Question 10

Where is the most common site for an ectopic pregnancy?

Answer 10

Wall of fallopian tube (halfway down)

Question 11

Where does normal implantation occur?

Answer 11

Endometrium

Question 12

What percent of cells in a blastocyst form the ICM

Answer 12

10%

Question 13

Where does the embryo begin to develop from?

Answer 13

The 2 layers of the ICM, which are ectoderm and endoderm

Question 14

What does the ectoderm face?

Answer 14

Amniotic cavity

Question 15

What does the endoderm face?

Answer 15

Yolk sac

Question 16

What does the yolk sac produce?

Answer 16

Extra-embryonic mesoderm

Question 17

Define gastrulation

Answer 17

Process which involves formation of 3rd layer (mesoderm)

Question 18

What marks the beginning of gastrulation?

Answer 18

Formation of the primitive streak by the thickening/increased cell division of the ectoderm

Question 19

At which end is the primitive node formed?

Answer 19

Cranial end of primitive streak

Question 20

What is the significance of the formation of the primitive streak and node?

Answer 20

At this point, the embryo has a head and tail end, with left and right sides

Question 21

How is the mesoderm formed?

Answer 21

Cells in primitive streak multiply/divide and push their way to form the new layer

Question 22

What are the primary germ layers?

Answer 22

Ectoderm, mesoderm, endoderm

Question 23

What is a sacrococcygeal teratoma?

Answer 23

Tumour where primitive streak continues to grow instead of degenerating after 2 weeks

Question 24

Where does the notochord grow from?

Answer 24

The primitive node end, beneath the ectoderm

Question 25

What is the significance of the notochord?

Answer 25

Essential to developing the nervous system and will later become part of the vertebral column

Question 26

During the time the notochord is forming, what is the most anterior structure of the embryo?

Answer 26

The heart

Question 27

Define neurulation

Answer 27

Process where the neural plate becomes the neural tube. This hollow tube will form the future brain and spinal cord.

Question 28

During folding, which germ layer multiplies faster than the other?

Answer 28

Ectoderm

Question 29

During folding, what does the yolk sac compose of?

Answer 29

Foregut, midgut, hindgut

Question 30

Describe somites

Answer 30

Located on both sides of the neural tube, made up of parts of mesoderm into blocks of cells. Will later differentiate into skin, muscle, bone etc.