Lecture 3 8/28/23

Question 1

How are metastasizing cancers named?

Answer 1

they keep the name of the original cancer

Question 2

What is a teratoma?

Answer 2

-a tumor with elements of all three germ layers
-often arise in gonads due to increased levels of undifferentiated cells

Question 3

What is the notochord?

Answer 3

-tube of mesoderm
-becomes part of vertebral column
-runs full length of body

Question 4

What is the neural tube?

Answer 4

-ectoderm over the notochord
-becomes neuroectoderm
-pinches off to form neural tube, which becomes brain and spinal cord

Question 5

What is the lumen?

Answer 5

the space inside a tubular structure (such as the neural tube)

Question 6

What does the lumen of the neural tube contain?

Answer 6

cerebrospinal fluid

Question 7

What is spina bifida?

Answer 7

failure of the neural tube to fully close?

Question 8

What are the types of spina bifida?

Answer 8

-occult: skin still closes despite neural tube not properly closing
-classic: skin over the neural tube does not fully close

Question 9

What are neural crest cells?

Answer 9

-cells that emerge during the pinching off of the neural tube
-not classified into the germ layers

Question 10

What do neural crest cells become?

Answer 10

-cells of the nervous system
-melanocytes
-adrenal medullary cells

Question 11

Why is it bad if neural crest cells fail to migrate?

Answer 11

-regions of the body can be lacking the cells that neural crest cells differentiate into
-can cause problems in development that can be fatal

Question 12

How do we name tumors that arise from neural crest cells, since they do not fit into any of the germ layers?

Answer 12

-benign tumors: name of cell + -cytoma
-malignant tumors: malignant + name of cell + -oma

Question 13

What does it mean for something to be multi-focal?

Answer 13

there are multiple spots (typically tumors)

Question 14

What are the 4 extra-embryonic membranes of the placenta?

Answer 14

-amnion
-yolk sac
-allantois
-chorion

Question 15

What is the chorioallantoic?

Answer 15

a fusion of the allantois and chorion membranes

Question 16

What is the purpose of the amnion?

Answer 16

to encircle the amniotic fluid and cushion the baby

Question 17

What is the role of the allantois?

Answer 17

surrounds the amniotic sac

Question 18

What is the connection between the allantoic cavity and the embryo’s digestive and secretory systems?

Answer 18

the allantoic cavity, digestive system, and secretory (waste) systems are all connected in utero

Question 19

What is the chorioallantoic placenta?

Answer 19

where the allantois and chorion fuse within the placenta

Question 20

What is the urorectal septum?

Answer 20

endodermal tissue that grows between the urethra and rectum to separate them

Question 21

What membrane is the gut continuous with?

Answer 21

yolk sac

Question 22

What membrane is the urachus continuous with?

Answer 22

allantois

Question 23

What is a cloaca?

Answer 23

a common passageway for urine, feces, and reproduction

Question 24

What are the characteristics of the umbilicus?

Answer 24

-contains outpouchings of the GI tract and urinary tract
-the tracts retract prior to birth and umbilicus pinches off

Question 25

What is the urachus?

Answer 25

a brach off the bladder that leads into the umbilicus

Question 26

What happens when a patient has a patent urachus?

Answer 26

-urachus remains open when it should not -animal now has an extra opening into the bladder which is prone to infection

Question 27

When does an umbilical hernia occur?

Answer 27

when the GI tract and urachus do not retract through the umbilicus prior to birth

Question 28

What is the anal membrane?

Answer 28

-ectoderm covering the rectum during development -breaks down to create the anus

Question 29

What is atresia ani?

Answer 29

when the anal membrane fails to break down, resulting in an animal without an anus

Question 30

What tissue gives rise to the liver and pancreas?

Answer 30

endoderm

Question 31

What are parenchyma?

Answer 31

-functional elements of solid organs -cells that provide the organ function

Question 32

What are stroma?

Answer 32

-supportive framework of solid organs -connective tissue and blood vessels

Question 33

What tissue gives rise to the respiratory system?

Answer 33

endoderm

Question 34

What tissues give rise to the urinary system?

Answer 34

endoderm and mesoderm

Question 35

How does the urinary system give rise to the kidneys?

Answer 35

-ureteric buds arise from bladder -buds interact with mesoderm to form ureters and kidneys

Question 36

What tissues give rise to the reproductive system?

Answer 36

endoderm and mesoderm

Question 37

How do the kidneys give rise to the reproductive system?

Answer 37

-three primitive kidneys form -one creates a mesonephric duct -this duct induces mesonephric tubules and mesonephros -gives rise to gonads, tubular genitalia, etc.

Question 38

What is the role of the chorion?

Answer 38

interdigitates with uterus