1. Which of the following are roles of stem cells in living organisqgtu shd/7 6r l/e76dlms?
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 different4-w 2 go w8xmksmq ehw/;p2b .p77hrfyiated cells in an individual plant such as the golden barrel cactusbarrel (Echinocactus grusonii) s8 s4hmb 2p o/wh2- pfrm q77wwxg.y;ekhown in the image?

  3. What are essentialu9zql8xz ; n+s properties of stem cells?

  4. What is the cause of stem cells diffegrum1q7k6s2 l w1tu, xrentiating along different pathways to produce a variety of differentiumqr,wkl 611ux2t s7gated cells?

a. Use the graph to 8ijv z2d)ik3 aestimate the volume of a liver cell.

b. The image is of cardiac n*q klaz. v8x(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 huq1q4g1(s *eg otvg;us man ovum has specialized to have a large volume.

d. Estimate the mean length of a cell with a volume of 1000 µm3 using/4tup zkf+ (ghj:3i0xa ic(wd the trend lijp 0 xacgwt4u: /3 (hfik+di(zne on the graph.

e. The horizontal errfvqk yli;b 4oy1 do 9(lz3xd(4or bars represent standard deviation. Suggest what the stand 1o (4l3x;oz 4qdify9y bvdl(kard deviation signifies.

f. Simplified models are commonly used to investigate scientific phe jg,x o69yk p+ete2xk/n-g;ycmym 3 0xnomena.
Outline the limitations in the use of a sphere to model surface area to volume ratio in cells.

6. Using examples from human tissues, dispt b ydgd.b2 zy2,.b:ytinguish between pluripotent, totipotent and multipotent stez d b,2.yyg2 .byb:tpdm cells.

7. Explain the role of stem cells in a multj-ipx7 t6u4x+f)hqc p iz4n3micellular organism.

(a) Explain why a large surface area to volume ratio can increb*l3ylz,qw t+ase cell efficiency. , wb +ltqzy*l3

(b) Describe, using two specific examplesntwtof/q::y.y qd o. /, how cell adaptation can increase surface area to volume ratio in a.q:ydoowf/n y /qtt :. specialised cell.

(c) Many tissues found in pl;jo9xhz rb87tz:4rc iants are compound tissues, such as phloem tissue shown in the image. Phloem tissue transports o7t xz;:9z4 ijro crhb8rganic 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