Cells, I guess? Flashcards
Membranes and stem cells
Membrane transport is important because…
- It protects metabolic reactions within the cell against the environment
- Allows for communication and exchange of materials between the cell and the environment
What is an electrochemical gradient?
Responsible for the movement of molecules resulting from the combination of the chemical and electrical gradients.
What is active transport?
Requires energy to move substances against the electrochemical gradient.
What is passive transport?
Moves substances down the electrochemical gradient.
What is a channel in passive transport?
Provides an aqueous pore for the passage of ions.
What is a carrier in passive transport?
Undergoes a conformational change that exposes ion binding sites to the different sides of the membrane.
What are co-transporters?
Couple the downwards movement of one ion (driver) to the uphill movement of another solute (substrate).
What is symport?
Driver ion and substrate move in the same direction.
What is antiport?
Driver ion and substrate move in the opposite direction.
What are unspecialised cells?
Reproduce indefinitely and can differentiate into one or more specialised cell types.
What is totipotent?
Generate all the tissue types of the embryo and extra-embryonic tissues.
Embryonic
What is pluripotent?
Generate all 3 germ layers but not the extra-embryonic tissues.
Embryonic
What is multipotent?
Ability to differentiate into multi-lineages but not all germ layers.
Adult
What is unipotent?
Ability to differentiate along only one lineage/cell type.
Adult
Transport proteins definition
allow for the controlled interactions of the cell within the environment
Transport proteins list
Creates a hydrophilic passage
Creates a filter
Provide possibility for energy coupling
Provide possibility for regulation
Autologous
take stem cells from an individual and return them to the same person
Allogenic
Take stem cells from an individual but administered to a different person
Reproductive cloning
Somatic cell nuclear transplantation
1. Differentiated animal cells
2. Remove nucleus from an egg
3. Replace egg nucleus with that of a differentiated cell
Challenges with mammalian cloning
- Small % of cloned embryos develop normally to birth
- Clones don’t always act the same
- Clones cell’s aren’t as healthy
Therapeutic cloning
Culture patient-specific cell lines in vitro
Patient nucleus + enucleated oocyte
Designed to replace injured/diseased tissues
Applications of embryonic stem cell
Research
Drug testing and discovery
Toxicology
Therapies
Teratoma
(Often) benign tumour containing tissues of more than one germ layer, arising from totipotent cells, often occur in the ovaries/testes
Somatic cells
Can be reprogrammed into induced pluripotent stem cells
