What property of water helps living organisms maintain their internal body tqx,pl veu;r g; 5cmpx 1)eq:(ya ;n5qvemperq ym ,an;(:51qgex uv)r;p;qe 5pxcvlature?

  Which of the following is not hpk*-y;k wc2 d.,icjh soluble in water?

  What substances are attracted to water and form intermpp8yrqll,z)d2h vu.tp( ;s/nolecular bonds with water mo q;v.u8s, d/)hl(lzy2pp rptnlecules?

  Which of the following is a reason fo yz0+ uii25q3ryho 2o gdxg-(mbo7 m0dr the retention of water on Earth?

  What is the most acceg /;)zf hrhuj ljkkw: 8b50(ftn.d(g e2wz)sspted theory for the origin of water on Earth?

  What intermolecular bond is responsible for water's cohesive, adhesive and tcp9rq,s2:g u lh ownd +jna3:7hermal propc:q9d, 7jp ow 2unhg:s n3rla+erties?

1.Outline how hydrogen bonds form betwee2)oe(lezey3 fnk7 n8o n 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 ena9 bis;mdb du*;bh 8wajq; 6u5ables marine animals such as the ringed seal (Pusa hispida) to stay afloat in watew;6*s dj8; ib 5bdhbuau;m 9aqr without expending large amounts of energy?

  The cohesive and adhesiveopg hi-ln g48sf.:r -o properties of water allow xylem vessels to transport water 4i- f r-os.o:ngglp8h 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 i yw7l( ,ts-ktls considered to be in ‘The Goldilocks zone’, bulwy-t k,lst7( t Saturn is not?

  Which of the following statements about the dipolarity of the water vr5*ndrrd - 2qmolecule are true?rrvnq-*d5rd 2
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 r7fknc , xty1hq* /:.fazqa4 g:e.gzfkeason that scientists look for the presence of water on ,az h*k:egq4 nq: f/ fy x.k1a.zt7cfgplanets as a sign of extraterrestrial life?

  Which term to describe a property of wat/u38,q1 t adklu+z 6cvip k+jmer is matched to its correct definition?d klu3jp6+uz1qcavi , /mt+8k

  The image shows a water strider (G. lacustris) on the surface of aejc6 (+:hji ay pond. What property ohjy :(ji+6aec f water is not depicted in the image?

Below is a picture of a water strider (Gerri*nb4j k ,8xmvss 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 Arc d r7l4lqfex r(bp7z(-tic 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 inm6 br:vy49pz ) qymdoxe1yo*(to the effects of household detergents on aquatic habit o*4dz:ypbv1qo6xmmy () yre9ats. Scientists tested the 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-lif6d)jig bg26i oe example of adhesion?

The image shows a cross-section of the vascular tissue of a woody dicot ste0out c/sd s2o(k5jmp 2m, showing the annual rings of phloe/ s umjo2ksodpc25t( 0m 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 bird that lives d8/ tua3l-n dj 9ukldo-( gz9mnear 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- uojkdl8/-3gn9md-ludt(9 azthroated loon?

  Which of the following statement(sj -n;jo gtu.w:) about the role of water as a solvent is correct? o.j u ;jtn:-wg

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-se(j6ii8h nx tw1,lwj0r ction of a stem from a plant in the Pinus g li j twj8h(0i1x6w,rnenus. 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, where )zcef 4l8- lcufive planets orbit a central stacu zf84 lcle)-r.


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 ev3**z20ob gwpnt eou 0volution of lif0e vwt2g o*3bzo*nu p0e on Earth?