1. Which of the following are roles of stem cells in living organis+fs. q qy2kl b,api0w.ms?
I. Growth of new organs.
II. Replacement of damaged cells.
III. Production of cells which could differentiate.
IV. Produce new stem cells by mitosis.

  2. Which of the following correctly describe the differentiasq6ng8q ,zb1us -tz5)/tokmcq;f w( rted cells in an individual plant such as the golden barrel cactusbarrel (Echinocactus grusonii) shown (mg-ucq5 f8szwb16 t q;zrn/o)skt, qin the image?

  3. What are essential properties of )8ybphugu c8- afq-:dyy n+y3stem cells?

  4. What is the cause of stem cells differentiating along gaeuu4(b;mo+ 5pb(ey different pathways to produce a variety of differentiatea;+gebey(u 5o4 m(bp ud cells?

a. Use the graph to estimate the volume o :z-4 5yj9blyspauty/f a liver cell.

b. The image is of carnc 1ifo 1-)kw ga(ot+ndiac muscle.

Cardiac muscle cells have a mean length of 100 µm and an estimated volume of 8000 µm3.
Explain why the cell length and volume ratios are not constant for all cell types.

c. Suggest one reason why a humanzg9o t/t1/cm ovpiow (8+h s-d ovum has specialized to have a large volume.

d. Estimate the mean length of a cell -brcc trj(i-*with a volume of 1000 µm3 using the trend line on the grap-c *-(ricbjt rh.

e. The horizontal error bt v*2g zg6wev8ars represent standard deviation. Suggest what the standard dev vztw6 2g8e*vgiation signifies.

f. Simplified models are commonly used to i 4rb +;milaw*av;zz:g nvestigate scientific phenomena.
Outline the limitations in the use of a sphere to model surface area to volume ratio in cells.

6. Using examples from human tissue,de 8g;uwdm pi(+va4yxf 65mps, distinguish between pluripotent, totipotent and mum wpeyv ;(dm4 fgi8up 5+dax6,ltipotent stem cells.

7. Explain the role of stem cells in a multicellularcnsv l6nj87v0 organism.

(a) Explain why a large su;)v qyqn,vrq0 rface area to volume ratio can increase cell efficiencyryq,q)v q;v0n .

(b) Describe, using two specific examples, how cell adaptcxz7vuozy ; :/ation can increase surface area to voluxu z7/yovz c:;me ratio in a specialised cell.

(c) Many tissues found in plants are compound tissues, sfrfvu opa3m0z326edn p(w. p/ uch as phloem tissue shown in the image. Phloem tissue transports organic nutrients from their site of production (often, the leaf) to sites of storage or metabolism (often floe33ud/prmf. vpp06 znw(o2 fawers or roots)

Compound tissues consist of several different cell types, simple tissues of only one cell type.
Outline why many tissues in multicellular organisms have more than one cell type in the tissue