1. Which of the following are roles os(4 / az8n nmi*,tifv+xyfom7 f 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 dif4cibuo4p 8 /kyoqe245mbr s -zferentiated cells in an individual plant such as the golden barrel cactusbark-44cy/4 eiurms opq 2zb 5b8orel (Echinocactus grusonii) shown in the image?

  3. What are essential properties of s jfec7;bae, w jk8oz(2e(l0udtem cells?

  4. What is the cause of stem cells differentiating * jg8 b1dw//rvfrk- kidh i-lsi.2wk2..h eefalong different pathways to produce a va. klvw-is.kbi*rdke 2ie//d. rj 1f 2-h8wgfhriety of differentiated cells?

a. Use the graph to estimate the volume of a liveraq6 d/2u/ mcwf cell.

b. The image is of cardiac m gs ecua j07.(p:knli.uscle.

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 tos* rxjkg+f2- p.naz 3vk(;;haww4 ovdi6*igh have a large volume.

d. Estimate the mean length of oc+uq 2q dblf)0wb0d4a cell with a volume of 1000 µm3 using the trend line on the graphc lo bwf)2d0qqb4u +d0.

e. The horizontal error bars rep y 8zczls-vj9s 1kn3u6resent standard deviation. Suggest what the stand6 k-usv jsc3yz n9z81lard deviation signifies.

f. Simplified models are commonly used to investigate scientific phenom)cl mn (1c8sqdl;9 orsena.
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 pluripotent, totlulob jt5/ o0-ipotent and m l5bo o/-0tjulultipotent stem cells.

7. Explain the role of stem cells in a muilq-awx m.y4r) 66jxflticellular organism.

(a) Explain why a large surface area to volume ratio can inci9-1( ,/lswj3x9g f8 xbiesav8z wrwdrease cell efficienc31z jlsafwx9 w(,e-bsx 9/rv 8dwg8iiy.

(b) Describe, using two specific examples, how cell adapefr, .-(asa djtation can increase surface area to volume r -(aad ,jser.fatio in a specialised cell.

(c) Many tissues found in plants ,mc ggf18psu hg.r3*aare 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 storage or metabolismrs 3u .gf8cg*ph,am g1 (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