1. Which of the following are roles of stem cells in living o+u uuf/ *ljcp(rganisms?
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 t2 w0nn w nd:l/ho0;7jbjz4)sirv l,xlhe differentiated cells in an individual plant such as the goldejib;4dl o7n2)vn/nll0jzx r0w:h w ,sn barrel cactusbarrel (Echinocactus grusonii) shown in the image?

  3. What are essential properties of stem cellsraw) ntd)uu l2n872g0pf0: eaxkjh y9?

  4. What is the cause of 2j 5vyf0pm) o;argqm) stem cells differentiating along different pathways to produce a variety of difffm2p );yr ao50g )vjmqerentiated cells?

a. Use the graph to estimate the vg ,-px+iorya3/ .m gcbyd 72rxolume of a liver cell.

b. The image is of cab)ztv 4g yp 1/x.i(wds3ijth4rdiac 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 human ovum has specialized to have a largtd690e:m,jqfww 2 mige volume.

d. Estimate the mean length of a cell with a volume of 1000 µ 7-y3erjo6k8 1qc2kwbj ; u8jjdndgy *m3 using the trend g6jj12-u3n 8 kd y7c8j yb;qdrk*ojewline on the graph.

e. The horizontal error bars repres c,xp62)+ o6nv drr8brjr-inhent standard deviation. Suggest what the standard deviati-dnbr+xr r,j6 o6incvph)28 ron signifies.

f. Simplified models are commonly used to investigate scientific pnsh/s uyv.e5d qy30p6:e q ,87bjryzchenomena.
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 pluripr/ jcr 2hu7k1totent, totipotent and multiputr cj7 k1/hr2otent stem cells.

7. Explain the role of stem cellsbs9* pjb)w7 qk in a multicellular organism.

(a) Explain why a large surface area to volume ratio can increase cell efficienk*0v5*, nt bjmqjmj- zcvm-jktqb5 0 ,mj* z*njy.

(b) Describe, using two specific examples, how cell adaptati2usb w8:c8ij- h3ui y2dqdya 3on can increase surface area to volume ratio in a s wau8d 2 3i2sbi:juyh83yd-qcpecialised cell.

(c) Many tissues found in plantstu92q. o9jm* rfo xg;t are compound tissues, such as phloem tissue shown in the image. Phloem tissue transports organic nutrients from their site of production (often, the leaf) to sites of s tqg; fut*mxjro9 o.29torage 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