Embryology

Question 1

What happens if there is a mutation in the homeobox?

Answer 1

Significant anatomical defects

Question 2

What do regulatory genes do?

Answer 2

Turn genes on/off

Question 3

Define morphogenesis

Answer 3

Shaping of an organism by embryonic processes, including differentiation of cells, tissues and organs

Question 4

What happens in the first 6 days following fertilisation?

Answer 4

1- zygote
2- early cleavage cell
3- morula
4- early blastocyst

Question 5

What happens to the blastocyst?

Answer 5

Cell division is asymmetrical and lose their totipotencu and begin to differentiate

Question 6

What do blastocysts differentiate into?

Answer 6

Inner cell mass= fetus
Outer cell mass= placenta

Question 7

What is formed in week 2?

Answer 7

Embryonic disc

Question 8

What is the ectoderm?

Answer 8

Skin
Nervous system

Question 9

What is the mesoderm?

Answer 9

Muscle
Skeleton
Kidneys
Reproductive organs

Question 10

What is the endoderm?

Answer 10

Endocrine glands
Lungs
Digestive tract

Question 11

What happens in week 3?

Answer 11

Heart and nervous system begin to form
Neural plate begins to form

Question 12

What happens in week 4?

Answer 12

Folding of the embryo into a C shape
Beating heart present

Question 13

What forms 25 days post fertilisation?

Answer 13

Placenta and umbilical cord

Question 14

Function of the placenta as a storage compound:

Answer 14

Stores glycogen to metabolise into glucose for fetus
Stores iron and fat soluble vitamins

Question 15

Placenta function as an endocrine:

Answer 15

Produces oestrogen and progesterone (steroid)
Produces HCG, HPL, PAPP-A/B

Question 16

How does the placenta get oestrogen?

Answer 16

The fetus causes that

Question 17

What does oestrogen do?

Answer 17

Growth of uterine muscle
Increases size of nipple and duct development

Question 18

Where is progesterone made?

Answer 18

Placenta
From cholesterol

Question 19

Purpose of progesterone?

Answer 19

Relaxes uterine muscle
Regulates storage of body fat

Question 20

Why do levels of progesterone fall after birth?

Answer 20

So prolactin can be formed and lactation can occurr

Question 21

What produces HCG?

Answer 21

trophoblasts from 7-10 weeks
Forms the basis of pregnancy tests

Question 22

What hormone does HCG stimulate the corpus luteum to make?

Answer 22

Progesterone

Question 23

What does HPL do?

Answer 23

Mobilises fatty acid from maternal body stores
Increases insulin levels

Question 24

Function of PAPP-A/B

Answer 24

A= prevents rejection of fetus from mothers cell mediated response
B= used to check progress of placenta in diabetes/pre-eclampsia

Question 25

Function of placenta with respiration:

Answer 25

O2 and CO2 transferred to and from maternal circulation from fetus by diffusion Mother will experience alkalosis

Question 26

How does the placenta act as a protection:

Answer 26

Acts as a filter to most bacteria Immunoglobulins from mother is passed to fetus during late pregnancy

Question 27

Function of the placenta in excretion:

Answer 27

CO2 is the main product excreted Bilirubin is also excreted

Question 28

Function of the placenta in nutrition

Answer 28

Fetus receives the raw materials for growth ( glucose, amino acids, FA)

Question 29

The function of the placenta with the transfer of substances:

Answer 29

Simple diffusion of lipid soluble water pores transfer water soluble F.D glucose using carriers A.T when transferring ions

Question 30

Maternal surface of the placenta:

Answer 30

Dark red Divided into cotyledons Cotyledons contain villi

Question 31

What’s in the cord?

Answer 31

AVA 2 arteries and 1 vein

Question 32

What are the names of the two placental membranes?

Answer 32

Chorion and amnion

Question 33

Features of the chorion (outer) membrane

Answer 33

Rough, thick and fibrous Produces oxytocin to stimulate uterine activity Continuous with the edge of placenta

Question 34

Features of Amnion (inner) membrane:

Answer 34

Smooth and translucent Joins onto cord Contains amniotic fluid

Question 35

What happens in week 8?

Answer 35

Fetal circulation is functioning External genetalia is present with anus Ossification of bones All organs are here

Question 36

What happens in week 11?

Answer 36

Fetus heart rate can be heard with a Doppler Has all organs for survival

Question 37

What happens in week 13?

Answer 37

Has fully formed limbs Uterus may pop outside of pelvic cavity

Question 38

Week 20

Answer 38

Halfway through Movements are easy to feel

Question 39

What is the surfactant?

Answer 39

Slippery substance that allows the alveoli to inflate and prevents collapse

Question 40

Week 24:

Answer 40

Baby should have a regular wake and sleep cycle

Question 41

Week 32:

Answer 41

Baby is head down

Question 42

Week 37:

Answer 42

Pregnancy is considered term

Question 43

Week 40:

Answer 43

Baby is fully term