What property of water helps living organisms maintain their aop kytin/3to: y; y23internal body temperature; kyypony:a3/3i2t ot?

  Which of the following iv pk5y a:s x3h.xoq0u4s not soluble in water?

  What substances are attracted txth8f 5,+fko po water and form intermolecular bonds with water molecule,x fhkt8pf+o5 s?

  Which of the following zn:cb); dxz6 fis a reason for the retention of water on Earth?

  What is the most accepted theory for th*h kx 4bwms()t+rf f8mr-/ pjs5su2oie origin of water on Earth?

  What intermolecular bond isqgd))smt9 -5fu zfe -c responsible for water's cohesive, adhesive and thermal prope 5s-mf u-ce9t)zdg q)frties?

1.Outline how hydrogen bonds form betweygmm j u 6yyml.jw99;;en water 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 marine animals such as the ringed seal (, hy)w,1r+ zmkkj :kwv25ubezPusa hispida) to stay afloat in water without kzb1,:2h+5 emy v,w)wk j ruzkexpending large amounts of energy?

  The cohesive and adhesive properties b0::u k twdr*4l0ktb uof water allow xylem vessels to transport wat4r :bt* 0b lw0u:tudkker inside plants.

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 considered to be inmol)*x , q(gqt4ofn3x ‘The Goldilocks zone’, but Saturn g o(*l,t3n4xqof)qmx is not?

  Which of the following statements about the*all ei.lwi8;ji4sa :.v9 mfg dipolarity of the water molecule are true? lli.;e mal9.*v j4gii:wsaf8
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 a reason that scie3cxfl-rj5vk w 7)oa q-5t,sz ao/3m7wmhjh .fntists look for the presence of water on planets as a sign of extraterr3fka-)l/3 qoo -7mf5m wa x5s,c.rvjh7 thwzjestrial life?

  Which term to describe a property of water is matched to its correct definitijr j*xl,8nq v:on? , jl:rqnx*vj8

  The image shows a water jdyfry21ga d* sn)3uq:m*t* i strider (G. lacustris) on the surface of a pond. What property otun d1)isdrqgyj f: ma2*y3 **f water is not depicted in the image?

Below is a picture of a w3idxdx n/op9i n4rk(-ater strider (Gerris sp.).


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 hispiv8 owj.oax+x;+5ds/si7-zleja x v4 n da) that lives in the 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 int /+j+s2e 1le9v aswou (l-qrlrkzmt. 7o the effects of household detergents on aquatic habitats. Scientists tested the effect of different household detergents on the surface tension of water in order to better understand the imp1a.9rro l q+l(s+v w kl 7tjzesue-m2/act 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 is not a real-lif:y-) xg wwzt(fe example of adhesion?

The image shows a cross-section of the vascular tissue of a k3 lvmn444qjk 8fwq yp.4ec.lwoody dicot stem, showing the annual rings of phlok jfy48.vqck l4wq 4plmen3.4em 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 (Gavia arctica) is a b nyyr6kf138g+b - g+wnm,of cfird 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-thrn8ff,+3yf 1 ybo-cg 6wkgnm+roated loon?

  Which of the following statement(s) about thk6).ruyy 6:l dlc-ywle role of water as a solvent is correct? -w.:u dyyk llry)6c6l

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 shows the longitudinal cross-section of a stem from ap 90+6rpg;g jy d24(0a werjhsbhrwu9 plant in the Pinus genus. Xylem vessels ar2jbrh6rrh gsp99 40(wj;yg0a u pwe d+e 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 similar to ours, w-p: h+w,fob/5 j -susa)rz/japfo b8ghere five planets orbit a central star/8fuo):-5o wbarp hpbj s+zajs-, gf/ .


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 following state:, 0w w(+bdtvtofk; qgments explains how water has facilitated the evolution og tq0 ow;b,t+df:w(v kf life on Earth?