What property of water helps living organisms maintain their int5h coq vwl;x, a*nz)rzpv7k5;ernal body temperaturn5*c )x rzv;whoq7vpz 5a,;l ke?

  Which of the following is not v ky-sy3t9gong.-pz 8g 4dg9 hsoluble in water?

  What substances are attracted to w 7iq-.kjs7u +lp9f dhwater and form intermolecular bonds with water mi+fhlsdj97 uw.7p -k qolecules?

  Which of the following is a reason fo kpq:s+ 4i4zxsi61fn yr the retention of water on Earth?

  What is the most accepted theory for the origin of water on Ep70 ig f)4yosdarth?

  What intermolecular bond is responsible for water's cohesiveenq1 pyx:m,o7, adhesive and thermm,yox1 ep:7qn al properties?

1.Outline how hydrogen bonds form between watta8) +/q uxboler 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 )ngeamx;nyjil3 *) q4as the ringed seal (Pusa hispida) to stay afloat in water without expending larij x)3g)ny mqa;e *n4lge amounts of energy?

  The cohesive and adhesive properties of water allow xypqd9b 6dany* q* g2x:klem vessels to transport water inside p6:kndpd *qaqyb2g* 9xlants.

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 j, sgiqty1.se8/ -yncthat the Earth is considered to be in ‘The Goldilocks zone’, but Sat1sc q-, ysygi8et/jn. urn is not?

  Which of the following statements abo,jle*4p w-:cze2wina1rpe j sp9x; ;put the dipolarity of the water molecule are true? l;sxw,p9pz1* i wpr-e24npej: ca;j e
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 sci:lgnxis8o2a *)4dg wcentists look for the presence of water on planets as a sign of extraterrestrialaox:w ) 4*2glc gind8s life?

  Which term to descriitr t7vr25x 4tbe a property of water is matched to its correct definition?r v5r4i 27txtt

  The image shows a water strider (G. lacustz q ak914 svyck3m(6onris) on the surface of a pond. What property of water is not depictey3z4o9n1(k6sv qmcak d in the image?

Below is a picture of a water stride3emi59tp:d4pmn(r 6.lfboubql q 9*t r (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 his.4d-u0nv q tjppida) 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 into the,d8q:;o( ocio.up uhe 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 to(hq pi8u.cou;de : ,ohe 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 hclwbt0+ cq +9jt6rf-is not a real-life example of adhesion?

The image shows a cross-section of the vascular tissue of a woody dicot s0 8bovcx i(l5 tu/,e5 brhe*kqtem, showing the annual rings of phloem and xylk*ib5ro l, /exhuv08cbeqt5( em.


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 loo7t1etdn9i; o6oh sz)- sfk vbkh(oq (,n (Gavia 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 kdhi(te so1k ;fb- 9qvt7,( 6zsohno)make winter temperatures more moderate for the black-throated loon?

  Which of the following statement(2qv42dfr-arw sghm by02t0,q nqm- 5ws) about the role of water as a solvent is correcaqm ns4mr2qyvrdw0g h,-0 bw5- ft2q2t?

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 a plan mlxh 3kw3red3jw.93cb69i cbt in the Pinus ged.bx3wj 639k39mrwlihc b 3ecnus. 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 similar to ours, wdeu; (bti ,7y;at/x,gsr oi +where five planets orbit aro t(u7swi;bt, ,xe/+g ;daiy central 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 statemeo u0/oc00 cgghnts explains how water has facilitated the evolution of 00cch go/go0ulife on Earth?