1. Which of the following are rolevkx pm 6(jyr (o3uj 081z ybj.sz+dr(js of stem cells in living organisms?
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 l -hg;lb7u b0v-qf k,g nquk(8.hn+kgdifferentiated cells in an individual plant such as the golden barrllq nk0k b-uvq,kf8g h. h-(+bnu7;ggel cactusbarrel (Echinocactus grusonii) shown in the image?

  3. What are essential properties of stem cells,o1 5sesd- fwust t gm+9irkb1+.z .zs?

  4. What is the cause of l3x *7mfhb+d(jc.gys stem cells differentiating along different pathways to produce a variety of differentiated cellsjs(m bghd+cl7f.3x * y?

a. Use the graph to estimate the volum3u;z d4wspvqch8 l3)we of a liver cell.

b. The image is of cardiac muscle. 833ans4 kd-* bp iowfz

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 humano;qh1s01wx cfm:jtp/ ovum has specialized to have a large volume.

d. Estimate the mean length o3 2cw tqp2.9:sdenvp cgrt.j,f a cell with a volume of 1000 µm3 using the trend line on the grapnj.p.eq w p29gc:sdvc,3 tr2th.

e. The horizontal error bars represent stan8gbvhr9v4h x *dard deviation. Suggest what the standard deviatixgb4h*r9v h 8von signifies.

f. Simplified models are commonly used to in gen)ye.t4f:3 svv2dgvestigate 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 tissues, distinguish between pluri7i) iwne o,pq8potent, totipotent and multipotent s i7 wqpoei,)n8tem cells.

7. Explain the role of stem cells in a mqqd0v00vht9(x kp9k xulticellular organism.

(a) Explain why a large surface area to volume ratio can increase cell efficiej6cj/fif-ll 4ncy. l-f 6/ i4jcfjl

(b) Describe, using two specific examples, how cell adaptation can i+j.uvq54sioj ncrease surface area to volume rqj4 suivj o.+5atio in a specialised cell.

(c) Many tissues found inkl8n3mdv;ob chy8yn zc/ y+4/ t 32jko plants are compound tissues, such as phloem tissue shown in the image. Phloem tissue transports organ ;d/z3 4cy3 j8m yvob2yl+kno/8tnhck ic nutrients from their site of production (often, the leaf) to sites of storage or metabolism (often flowers 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