Developmental biology Flashcards
(19 cards)
What are the 2 aspects of development
Growth and differentiation
Which structure embeds itself in the womb and what is its structure.
The blastocyst. It has an inner cell mass with an outer layer of cells around it. ICM forms the embryo and Outer layer of cells forms placenta
WhIch process occurs after it has been embedded in the womb.
Gastrulation. this involves further differentiation of the inner cell mass of the blastocyst. they form the ectoderm, mesoderm and endoderm cells
What organs do the ectoderm, mesoderm and endoderm cell form
Ectoderm - skin, nervous system
Mesoderm - Blood, heart, muscle
Endoderm - Pancreas, liver, Gut, lungs
Name the order of progressive differentiation to a beta islet cell
ICM cell, endoderm cell, pancreatic bud cell, endocrine pancreas cell, beta islet cell.
What is progressive differentiation dependent on
Epigenetics, the “switching on and off of genes”
What determines cell fate - how a cell moves between stages and what determines it
Cytoplasmic factors - transcription factors that control which genes are translated - CHECK ANSWER ON PADLET L13
Cell-cell interactions - cells can release things like cytokines and growth factors that affect other cells
L13 22:04-22:59
What are the 2 essential properties of stem cells
Self-regeneration and differentiation
types of stem cells an where they are found.
Totipotent stem cells - fertilisation
Pluripotent - blastocyst
Multipotent - adult stem cells are tissue specific
What are the differences between embryonic and adult stem cells
Embryonic - plentiful, can form all cell types, immortal in culture
Adult - tissue specific, can form a few cell types, hard to isolate, limited life span
Define regeneration
The reactivation of developmental processes to restore missing or damaged tissue
Why are planaria able to regenerate
They are rich in stem cells called neoblasts. theses neoblasts are rich across the whole organism
How does a newt regenerate limbs
- Wound healing - inflammation, clotting, formation of wound epidermis.
- Blastema formation - Cells at the site of the wound dedifferentiate to form the blastema. Which can divide to give rise to new cells
Why is mammalian regeneration limited
- Cancer risk
- Lost or altered genes
- Smaller stem cell pool
What is CD59 and what does it do
It’s a cell surface protein which is graded down along the newt limb. When the limb is severed/damaged the cells can look the the concentration of CD59 to see how much of the limb needs to be regrown. CD59 gives the cells an address of where they are along the limb.
What is a cancer stem cell
Rare cells within tumors with the ability to self- renew and give rise to the phenotypically diverse tumor cell population to drive tumorigenesis
What is Tumorigenesis.
Tumorigenesis, also called oncogenesis or carcinogenesis, is the process by which normal cells transform into cancer cells. It involves genetic and molecular changes leading to uncontrolled cell growth and tumour formation.
