What property of water helps living organisms maintain their intern+-yryo9)j - 7 n3lmau7imlsural body temperaturm7lu-mij ns3-ay +yr )79oulre?

  Which of the following :k7h.mc;5 p pgbzwb/nis not soluble in water?

  What substances are attracted to water and form intermolecular bonds wz7; og:ec: mma-ro tn)en p+d7ith water molecules-:7ommne+ep orz;:d 7agtcn) ?

  Which of the following ll ,:1lth0md9i uq/:k /ualpm is a reason for the retention of water on Earth?

  What is the most accepted theory for the origin of wsz-g c6wkzv v.o w4/5e:h2rq4(gf obdater on Earth?

  What intermolecular bond is responsible a,h27d5wx6ma(jlwj0h sa-z5mwpo9m:7 bnpu for water's cohesive, adhesive and thermal propertp752 wm m,d:0ouwhbjxw 6lhja s(a z p7m9na-5ies?

1.Outline how hydrogen bo;(c 0r(glwa mqnds form between 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 riv:vfoyv;- 0v jnged seal (Pusa hispida) to stay afloat in water withv vj -0vfyv:;oout expending large amounts of energy?

  The cohesive and adh2w. th/8zuxs zesive properties of water allow xylem vessels to transport watertz.x /uzwsh82 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 requgc:8t uzq7/uj )6 is considered to be in ‘The Gold7g8 c j6uzu:rqq )etu/ilocks zone’, but Saturn is not?

  Which of the following statements about the dipolarity of the water molecatjgl g9b7 qz*( m61(cmk qcu(ule are true? zul7tq*ma9 mg( (c1qcjg6k (b
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 scientists look;8,d3vb:4,h bc1qt zhc 3 jnghco n.op for the presence of water on pg,jpbc 4odt.n 8cqh3,zo: v1 ;3nb hchlanets as a sign of extraterrestrial life?

  Which term to describe a property of water is matcu 3g3(bsgw 3zohed to its correct definition?gz33(3ow gubs

  The image shows a water strider (G. lacustris) on thew0fx:h;z5t* mjf met/ surface of a pond. What property of water is not depicted *wm x5e:t /0j mhfz;tfin the image?

Below is a picture of a water strider (Gfy/kdw. ,7bfx x yny. 0e2dls1erris 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 hispida) th,/eu jx t,.wveat 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 into the effects of householdk)v0i8qzp,e ls kep*8 detergents on aquatic habitats. Scientists tested the effect of different household detergents on the surface tension of water in order to better understand the impact z,e)8 i l*p8qv0sekpkthey 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 nt03re/l;yk l jot a real-life example of adhesion?

The image shows a cross-section of the vascular tissue of /a nthdv(,owow432fo a woody dicot stem, showing the anha2f o3(o,t wwd4 vo/nnual 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 (Gavia arct k *q sq4ahu;*z6rv*ybica) 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 za4k*r*v uy*q 6s;hbqmake winter temperatures more moderate for the black-throated loon?

  Which of the following statement(s) about the role om;synn;vx *tw o8)al .f water as a solvent is correct? nmw.aotvys;)8lx*n;

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-s9q2-ephge1+w :s bo kxection of a stem from a plant in the Pinus genus. Xylem vessels are clearly vis9 +qe1px:eog2k-bhw sible.


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, where five pla wn3ih l2yb0d2xvo a1r8 l*f5anets orbit a central star. ixh 5aoydw2a2l3*bv1 f nlr08


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 statements explains how w(e.paq-k7 p zzater has facilitated the evolution of life on Eap(z7-e pzq k.arth?