What property of water helps living organisms maintain their interu8tipf6 oov sb52 m4.hnal body temperature?vsi8 2tuf b6mo4ho.5p

  Which of the following is not,- yabz8px3:ho nexg/p,;;wr i5xsj f soluble in water?

  What substances are attracted to water and form intermolecular bonds with waterevsy- rfdf066k8l6o h mook6y6s -0flv6rd8fhelecules?

  Which of the following is a reason for g7df:is:s,ol the retention of water on Earth?

  What is the most accepted theory for the orixjv q(ogwq7w0/ -w8-t k6tksegin of water on Earth?

  What intermolecular bond is responsible for water's me6hn1x8z,),g rzr7nnp * a macohesive, adhesive and thermal propert gnzrp)xm8h6,7ne az amr,1 *nies?

1.Outline how hydrogen bonds form ccq ) /o4as:u tyo7bj,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 s-hru)jheq r +aemo:10gbc/4kuch as the ringed seal (Pusa hispida) to stay afloat in water without expending large amo -hm: k oauq1+er/40eb)jrhgcunts of energy?

  The cohesive and adhesive properties ofe .ra..pj hah) water allow xylem vessels to transport water inside .rpja).h eh a.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 thayef. adf)1 mj *h2nitr+* lly.t the Earth is considered to be in ‘The Goldilocks zone’, but Saturn is notf.h)n * d1il+erf yj*.2mylat ?

  Which of the following statements0pmi8 ggm b9ez.r2g7 b about the dipolarity of the water molecule are tbi2.mggz r7ebg8p09 m rue?
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 for the presencebkrof ); 01w59 tj*ca7otz lsu of water on planets as a sign of extraterres;k0) 5bu jtt7awfsc oor*l1z9trial life?

  Which term to describe a property of water piy s/g+un6:0r fmce *is matched to its correct definition?guf:c+ 6ipye* r0nm/s

  The image shows a watetqz31 +f*9rijddb;pp r strider (G. lacustris) on the surface of a pond. What property of water is not d3pp+ rq19df iztj;bd*epicted in the image?

Below is a picture of a water strider (8ou1osmze.z dkm i9,wnd()a - 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 hispida) that lives in the Arctic Sea. wxu5 ig,y6qsfm2q x6joa -5- s


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 h99.7)vkwbr 0img vzl sousehold detergents on aquatic habitats. Scientists tested the0vsivz w.9mg7lr)b k 9 effect of different household detergents on the surface tension of water in 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 is not a real-life examp;st9 whpt): n8cx-ir:ygxys 9le of adhesion?

The image shows a cross-section of the vascular tissue of a woody dicot u5/e8sn5bxh o stem, showing the annual rings of phloem aeo8b 5/x5 shnund 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 bird that lives near large ok;a )e( cjy-pbodies of water in cold climates. Which of the following is a correct desc;ack pe -(o)jyription of how the properties of water may make winter temperatures more moderate for the black-throated loon?

  Which of the following statement(s) about the role of water as a solven. ,r+ lm n5fvzcyeib0+t is correct? mvbl.rc+5yne, 0iz f+

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 theozv 6cq 5yt.g2p4k) ib+ un4rhwlw1i0dra*c- longitudinal cross-section of a stem from a plant in the Pinus genuu hq0o) gprv.rl4 1bcaz- wi46y+ kw5t*nd2ics. 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 s qja0b( i9kpw/t cg)p yw3:fi8olar system very similar to ours, where five planets orbit a centra(wcw tfjk)3qgp:biaiyp9 80 / l 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 following statements explains how water has facilitated the evopx 6gi 8n/i2belution of life on Earth?ng 26i8ei /bpx