Review of Developmental Biology

Question 1

Genome

Answer 1

Every cell in the body has the same one

Question 2

lineage of every cell in the body

Answer 2

Can be traced back to the pluripotent stem cells of the blastocyst

Question 3

First Stages of development

Answer 3

1) Ovulation 2) Fertilization 3) 2-Cell stage 4) Morula 5) Blastocyst 6) Early stage pf implantation

Question 4

Zygote/Morula

Answer 4

totipotent

Question 5

Totipotent

Answer 5

ability for all things, give rise to fetus and support tissues

Question 6

Fetus

Answer 6

stem cells of the blastocyst make only the fetus

Question 7

Pluripotent

Answer 7

Ability for many things, produces 3 germ layers

Question 8

self renewal

Answer 8

ability to divide and produce new stem cells

Question 9

differentiation

Answer 9

process by which an unspecified cell becomes specialized

Question 10

Hayflicks limit

Answer 10

the number of times a cell can divide before it senesces (can’t divide anymore

Question 11

Hayflicks limit of human cells

Answer 11

about 50 duplications in our cells

Question 12

How many duplications have occured at birth

Answer 12

about 45, five more for adults

Question 13

Lab mice telomeres

Answer 13

extra long, resistant to injury or poison but they are way more prone to cancer because they choose tissue repair instead f tumor suppression causing uncontrollable

Question 14

Ectoderm

Answer 14

outer surface, central nervous system, pigment cell

Question 15

Mesoderm

Answer 15

Dorsal (Notochord), Paraxial (Bone tissue), Intermediate (tubule cell of the kidney), Lateral (Red blood cells), Head (facial muscles)

Question 16

Endoderm

Answer 16

Digestive tube (Stomach cell), Pharynx (Thyroid cell), Respiratory Tube (Lung cell (alveolar cell)

Question 17

Germ Cells

Answer 17

male (sperm), Female (egg)

Question 18

Differentiation

Answer 18

during development, stem cells and progenitors become increasingly specialized by differentiation

Question 19

terminally differentiated

Answer 19

cannot give rise to cells that are more specialized

Question 20

direction of potential developmental cells

Answer 20

Totipotent- Pluripotent- multipotent- Limited differentiation potential- Limited division potential- functional nonmitotic neuron

Question 21

Organogenesis

Answer 21

E8.5, reorganiztion and differentiation of cells from the 3 germ layers to produce tissues and organs

Question 22

Morphogenesis

Answer 22

Spatiotemporal coordination of cell differentiation, growth, migration, and death to form patterned tissues to produce functional body structures (requires precise signalling and gene regulation)

Question 23

Example of Morphogenesis

Answer 23

forelimb, cells in intra-digital webbing die on E14 in mice, but survive in bats

Question 24

Apoptosis

Answer 24

programmed cell death- like the webbing between mouse paws

Question 25

Necrosis

Answer 25

Unplanned cell death, cell gets injured or poisoned, bursts in a way that releases all kinds of danger cues (negative)

Question 26

Scavenger cells

Answer 26

eat healthy and unhealthy cells equally, the unhealthy one preferentially, helps to feed surrounding cells

Question 27

Intermediate fasting

Answer 27

Body looks for energy, gets it from food, by not eating for long periods of time repeatedly the body will train itself to go after the unhealthy cells and poptentially anything cancerous

Question 28

Spatiotemporal control

Answer 28

cells have to know where they are within the embryo, and when to divide, differentiate, migrate and sometimes die

Question 29

Organizers

Answer 29

Groups of cells that instruct fate of other cells by releasing signals (morphogens liek SHH, BMP4, and Wnt are made in specific regions of the embryo and work in concert with transcription factors like Myf5, Pax3/7, and MoD to direct developmetn

Question 30

transcriptional control of patterning and morphogenesis

Answer 30

expression of hox genes defines anterior-posterior axis along the paraxial mesoderm (regulated by morphogens)

Question 31

Forced expression of HoxA10 or Hoxb6

Answer 31

throughout the paraxial mesoderm dramatically changes A_P axis