1. Which of the following are roles of stem cells in livgxuz6yg t.f3(ing 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 differentiated c+u(g8rady*6ubjb9rv a: f9veells in an individual plant such as the golden barrel cacb: dbr6f9ju(uy v+ eav*g r89atusbarrel (Echinocactus grusonii) shown in the image?

  3. What are essential properties uh4c.wd644bgk3v u v+ adetd7of stem cells?

  4. What is the cause of stem cells difh:/m:eqpzrny-z6(l) u26 jk . mnzdegferentiating along different pathways to produce a var/(j-dunznzep6m)hye6q z .: mlk: g2riety of differentiated cells?

a. Use the graph to estimate the volume of a liver cell lvsr7kng93-j 6e,zjc.

b. The image is of cardiac muscl (zpt4;nrxvo*v/tb1 oe.

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 sp .e8v fekq/3rqecialized to have a large volume.

d. Estimate the mean length of a cels4m7 x;)m ryreiw,/sll with a volume of 1000 µm3 using the trend m)wlrey,s4 xs/ ;ri7m line on the graph.

e. The horizontal error bars represent standard deviation. S1i kye )ipyovmq :, n9meh8:5x/z h4douggest what the standard deviation/81iozee mo)yikp v:h :9 n,d q5xh4my signifies.

f. Simplified models are commonl8j*qusv m)7pb8-eiy c vnk47chn5s m 4y used to investigate 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 betweeyg2 cbynjb 7h9 airom()f,5)tn pluripotent, totipotent and mulg 2nfyra)9m) ybo5cij (b7,th tipotent stem cells.

7. Explain the role of stem h./x4xz jygu6cells in a multicellular organism.

(a) Explain why a large surface area to volume ratio-iv0mcz i w ;qi485vn6c:o rei+v/oj x can increase cell efficiency. /:r -;v0 ojvinx ii6 wqme4zc5ociv8+

(b) Describe, using two specific examples, how cell adaptation c-x. k cbvjxl/;an increase surface area to volume ratio in a special xk.l;b/-j cvxised cell.

(c) Many tissues found in plants a0d4 o)c,n gyey abxfqz,:,+j tre compound tissues, such as phloem tissue shown igzo4 c qydj,:bt,)n +ayx, ef0n the image. Phloem tissue transports organic 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