Exam 3 Dr Zaidi Flashcards
T/F: the higher the function, the higher the amount of labor?
True
What causes differentiation; the essence of development?
Selective expression
Purpose of proliferation in the development phase?
To create many cells to survive; “strength in numbers”
Purpose of specialization in development phase?
Cells start to express different characteristics/phenotypes
Purpose of interaction in the developmental phase?
Cells gain unique features via “talking” by chemical signals
Purpose of migration in developmental phase?
Cells that are alike come and move together (forms tissues and orgnas)
Why do cells have memory?
Have all the right components of signaling pathway and the ancestral signals/markers
What does it mean: homologous proteins are interchangeable
Genes are able to still perform their function in a different environment
The fertilized egg is cleaved to form:
Blastula (first layer)
Gastrulation of the blastula creates
Gastrula
What are the gastrula’s 3 layers and what do they form?
Ectoderm = NS and epidermis Endoderm = gut, liver, and lung Mesoderm = muscles and CT
Genes that are relatable in other species bc of a common ancestral DNA sequence
Homolog
Gene regulatory proteins control:
Genes
What are introns and what do they do?
Non-coding DNA that contain the biding sites for different TFs ie control the genes and provides uniqueness
What are exons
Coding sequence of DNA
What does it mean to be determined
Will become a cell type despite changes in environment
What does it mean to be completely undetermined
Potential to change fate because of changes in the environment (can change rapidly)
What does it mean to be committed?
Cells that have some attributes of a particular cell type but can change with environment
What does asymmetrical division mean?
Division is unequal
Cells born identical can change/become different how?
Due to changes in environment, different molecules induced
What is inductive signalling?
Group of cells acquired a molecule that turned on a pathway. They can now secrete a molecule that diffuses through and affect other cells; induction of a different developmental program
What are morphogens?
They are molecules secreted from inductive signaling that induce a different developmental program
Morphogens that are short range function:
Cell to cell contact
Long range morphogens function:
Diffuse through extracellular medium
