What property of water helps living organisms maintain tho9j 1 i0l3i0z*egk s;ivft roqb(er,6eir internal body temperzof9i06,er3rv1t ibokg* jilq 0(es; ature?

  Which of the following is no8wb2-proipw/8n ibwngrjjz4d:( ) zn v)q2 o8t soluble in water?

  What substances are +s;qxfcd faol42iu 87attracted to water and form intermolecular bonds with water o8ad+ i4f;u2x cs7qlfmolecules?

  Which of the followip,bq4n yb : c-tkwt3x //5sq1z 6fksqhng is a reason for the retention of water on Earth?

  What is the most accepted tu3 g:lm ax8kd.3-k 86z vletxtheory for the origin of water on Earth?

  What intermolecular bond is responsible for water'scdpzed fak1d/f*1cj 62 jx2u5 cohesive, adhesive and thermal propertied1axzk j21d 6cc/j5*dfpuef2s?

1.Outline how hydrogen bonds form between water gmn ci9bsb1 zr9jn063 molecules.

2.State one of the ways how hydrophilic substances interact with water.

3.State one of the ways how non-polar molecules interact with water.

4.Distinguish cohesion and adhesion.

  Which property of water enables maymf)ox q3f- md3s3xc5 rine animals such as the ringed seal (Pusa hispida) to stay afloat in water without expem3- sfxqc 5m3oxy3f) dnding large amounts of energy?

  The cohesive and adhesive properties of 3 p.o(e4am y lno2fmf8tww0d4water allow xylem vessels to transport water inside pl0m enyt m.a42wod8 3p( olff4wants.

Which of the following are correct descriptions of how these properties are related to water transport in plants?

  Which of the following is a reason that the Earth is:b;*xbso)77n nd00b p ixnma z considered to be in ‘The Goldilocks zone’, but Saturn isn7b 0zx:7)ndab pinosxb*;m 0 not?

  Which of the following statements/s zmx:6rq7t+2 8;zk slc;pscn(meem about the dipolarity of the water molecule are crq/p m s6kzz(28mxmne s:t;;7 cls+etrue?
I. Oxygen attracts the shared electrons stronger than hydrogen.
II.Hydrogen atoms are partially negative.
III.The shared electrons spend more time closer to oxygen.

  Which of the following is not g,nvol /he9vf69mkg 0 2iyu 0ca reason that scientists look for the presence of water29vlicv6h0k,y g9uo0en m / fg on planets as a sign of extraterrestrial life?

  Which term to describe a property o+5 9t0yjda qeof water is matched to its correct definition?q05d +oe tjay9

  The image shows a water strider (G. lacustris) on the m+a..j9z 5 5 dpz 9m*ys qy9zccqwq/zisurface of a pond. What property z/zdzzw9qcajy 9iq*5q.cs9ym 5+ mp .of water is not depicted in the image?

Below is a picture of a water strider (Gerris ehc .j-qf*f6 vsp.).


1.Explain why the water strider (Gerris sp.) does not sink.
2.Describe, using an example, the importance of water as a solvent in living organisms.

The image shows a ringed seal (Pusa hispida) that lives in t/cd8xx a v8h+kc8m gr+he Arctic Sea.


1.Distinguish between the physical properties of air and water that allow the seal to mostly live in the sea.
2.Ringed seals glide into the water head first from ice shelves, rather like humans diving into a pool head first. Explain the advantage of entering the water in this way rather than ‘belly-flopping’ into the water.

  An investigation was carried out into the effectiljnra9+ /qk nhkmy8 4 ud+g0.s of household detergents on aquatic habitats. Scientists tested the effect of different household detergents on the surface tension of water in d8 0ul+ nk9ny+a4qk.gmj irh/order to better understand the impact they may have on organisms living on the surface.

A paper clip was folded slightly on one side and rested on the surface of the water, maintained at a constant temperature and contained within a water tank. Drops of detergent solution were slowly added to the water tank until the paperclip sank to the bottom. The volume of detergent solution taken to sink the paperclip was recorded.

Detergent solutions were made by adding 5 ml of detergent to 15 ml of water.


1.Describe the relationship between the volume of detergent solution added and the surface tension of water.

2.1.For the Easy Clean detergent, calculate the mean number of drops of detergent needed to sink the paper clip.
Mean =  ml
2.2.Estimate how many drops of Easy Clean detergent solution it would take to sink 5 paper clips.

3.1.State one variable, other than those given, which would need to be controlled in this experiment in order to achieve a valid result.
3.2.Suggest one method that could be used to keep the water at a constant temperature.
3.3.Explain the importance of maintaining water at a constant temperature.
3.4.Identify one potential source of error in the methodology.
4.Suggest why different numbers of drops of detergent solution were needed to sink the paperclip between each type of detergent.

  Which of the following iv*gwaesd/r* 8jd0i i4f +fq4 bs not a real-life example of adhesion?

The image shows a cross-seck4e t0(sx vwc6fy w(l8+,lefsmx v+a .tion of the vascular tissue of a woody dicot stem, showingvem,6k y+sc(v+ l8l e( 0xxt.a4fwf sw the annual rings of phloem and xylem.


Explain how the properties of water allow it to be transported in the xylem.
Describe a physical property of water, other than those that are important for the movement of water through the plant, that makes water essential for the survival of plants.
Outline why plants cannot use water to transport lipids.
If the temperature drops to -1$^{\circ}$ for a few hours suggest a reason why the water in xylem may not freeze.

  The black-throated loon (exhssn1g1m .200 )2 vb yjhj-0rzevkeGavia arctica) is a bird that lives near large bodies of water in cold climates. Which of the following is a correct description of how the properties of water may make winter temperatures more moderate for the black-thro) b -v0jn2 xsjsy .011gekhr0eh zev2mated loon?

  Which of the following statement(s) about the role of water a(e4wp5x bx.5moas( rc+v )rors a solvent is correct? e5.x wor(( vx oabr+s4 m)crp5

I. Salt can dissolve in water because it is hydrophilic
II. Lipids cannot dissolve in water because they are non-polar
III. Cellulose can dissolve in water, as it is able to form hydrogen bonds

  The micrograph below+m)zx e7qnfze 4. kb4hbv6 pf+ shows the longitudinal cross-section of a stem from a plant in bfe4 6z 7)bm ef+kn+v.4xzhqpthe Pinus genus. Xylem vessels are clearly visible.


The xylem is composed of hollow, tube-like tissues that transport water through capillary action. What property of water explains capillary action?

The diagram shows a solar system very similarx1m s-bdv rvh 91lhy/ ju:kz2; to ours, where five planets orbit a cenh v/- 9uld:shvj1z ;k2m1bx yrtral star.


1.Define the term “Goldilocks zone”.

2.1.Label with the letter R the planet that is least likely to have extraterrestrial life present.

2.2Explain reasons for your answer to part (i).

3.1.Some of the planets in this solar system have water present on them. Suggest where this water might have come from.

3.2.Explain why the planets referred to in part (i) have retained water, whereas others in this solar system have not.

4.Suggest one other biological molecule, other than water, that may be a sign of life on a planet.

  Which of the followin 17j26rtit b2q jlmmtb.ldk 9k;:ah6ag statements explains how water has facilitated the evolution of life on Eaql9;hj dl ma22:k.mr7 b titj6katb61 rth?