stem cells and totipotency

Question 1

what is differentiation

Answer 1

when cells develop into specialised cell structures

Question 2

how do single cell organism carry out function

Answer 2

one cell carries out all the functions adequately but cannot carry one out efficiently

Question 3

what are the cells in multicellular organisms

Answer 3

they are adapted to carry out specific roles and functions

Question 4

how do multicellular organisms start off

Answer 4

a tiny ball- zygote of identical cells

Question 5

what happens as the cell starts to differentiate

Answer 5

dvelop individual characteristics that allow them to carry out function efficiently

Question 6

what do all cells contain and why

Answer 6

they all contain the same genes as they start to mitotically divide of the zygote

Question 7

so what does this mean in terms of capability

Answer 7

all cells are capable of making every protien in the body

Question 8

so why arent all the protiens produced by every cell

Answer 8

only certain genes are expressed in only one cell at a time

Question 9

what genes are permanely expressed in all cells

Answer 9

such as enzymes for repiration, transcription and translation of protien ass all cells carry out these process

Question 10

why are differentiated cells different visibly

Answer 10

they produce different protiens as a result of the different genes expression which causes them to look different

Question 11

what is totipotent

Answer 11

when s cell can develop into any body cell such as a zygote and later become differentiated

Question 12

so har are the specified protiens made

Answer 12

only the section of dna for a particular polypeptide is translated and transcripted to make the desired gne

Question 13

what can they do but dont do

Answer 13

they can stimulate other protiens but doing so would be wasteful

Question 14

how do you activate the other protiens

Answer 14

enable transcription and translation

Question 15

what is the limitation of specialised cells

Answer 15

their differentiation is usually irreversible eg red blood cells

Question 16

what are stem cells

Answer 16

undifferentiated cells that have the ability to mature and differentiate into other cells

Question 17

what is special about stem cells

Answer 17

occur in a adult cells and constantly dividing and make identical copies of themselves -self renewal

Question 18

where do they come from

Answer 18

embryonic stem cell
umbilical cord
plasma stem cells
adult stem cells

Question 19

what are embryonic stem cells

Answer 19

they come from embryos in early stage of development and can differentiate into any cell

Question 20

what are adult stem cells

Answer 20

found in featus and continue to find in adult TISSUES they are specific to a tissue or organ and replace the damaged cell or repair through self renewal

Question 21

what is totipotent

Answer 21

found in zygote can differentiate into any cell, usually only slightly develop into a more specialised cell like a pluropotent

Question 22

what is pluripotent

Answer 22

found in embryos and can differentiate into nearly almost any type of cell and form more specialised multipotent

Question 23

what is multipotent

Answer 23

found in adult stem cells usually differentiate to limited particular UNIPOTENT type of cells eg blood marrow to blood cells develop into unipotent

Question 24

what is unipotent stem cells

Answer 24

any body cell can only differentiate into one type of cell made in adult tissue

Question 25

what is an induced pluripotent stem cell

Answer 25

type of pluripotent cells formed from unipotent cells

Question 26

what happens to these unipotent stem cells

Answer 26

they are genetically altered and we add transcription facotr to induce genes

Question 27

what does this do

Answer 27

turn gene on which were turned off

Question 28

what is special about ips

Answer 28

they are very simmilair to embryonic stem cell and can almost differentiate into any cell

Question 29

however what are the differences

Answer 29

they may be made from different material , and also can divide indefinately as they are self renewal

Question 30

what is a strength of using ips

Answer 30

no need to use embryos so maneuvere the ethics

can help treat disease a

Question 31

what are the weakness

Answer 31

they have the potential to also cause disease

Question 32

why do we prefer to use zygote and embryonic in research

Answer 32

as they have the greatest potential to differentiate into any cells and treat disease

Question 33

how are the cells obtained

Answer 33

the extra embryos that are left over after ivf treatment

Question 34

when is such research allowed

Answer 34

only under strict condition in attempt to treat diseases

Question 35

what is done to the embryos

Answer 35

they are cultured in nutrients which causes the inernal mass to be released

Question 36

what happens to this mass

Answer 36

chemicals are added which breaks the mass up into smaller groups

Question 37

what happens to the groups

Answer 37

they are grown in colonies of embryonic stem cell and then added differentiated factors

Question 38

what do people consider about using human embryos

Answer 38

they arent human before the age of 14 dyas
however we shouldnt make an embryo suffer for no reason
its just a ball of cells