inorganic ions + water

Question 1

what is magnesium used for in animals?

Answer 1

allows teeth and bones to develop

Question 2

what is magnesium used for in plants?

Answer 2

needed to synthesis chlorophyll to allow photosynthesis to occur

Question 3

what is iron used for?

Answer 3

component in haemoglobin which carries oxygen in red blood cells
(lack of anaemia)

Question 4

what is calcium used for in animals?

Answer 4

important structural component for bones and teeth

Question 5

what is calcium used for in plants?

Answer 5

important structural component for cell walls

Question 6

what is phosphate used for?

Answer 6

needed to synthesis nucleotides (e.g. RNA, DNA)
component of phospholipids in cell membranes

Question 7

what are the bonds between atoms within the same water molecule?

Answer 7

single covalent bonds

Question 8

what are the bonds between two water molecules?

Answer 8

hydrogen bonds

Question 9

what charge are the hydrogens in water?

Answer 9

partially positive

Question 10

what charge are the oxygens in water?

Answer 10

partially negative

Question 11

why is water a polar molecule?

Answer 11

because it has separate charges due to the unequal sharing of electrons
electrons from the hydrogen atoms get pulled towards the oxygen atom

Question 12

why do electrons from hydrogen get pulled towards oxygen in water?

Answer 12

the oxygen atom attracts electrons a little more strongly than hydrogen does

Question 13

why is water a solvent?

Answer 13

water molecules are dipoles so they attract charged particles which dissolve in water

Question 14

why is it important for water to be a solvent?

Answer 14

acts as a transport medium
(animals - plasma)
(plants - minerals in xylem and sucrose in phloem)

Question 15

how does water have cohesion?

Answer 15

water molecules attract each other forming hydrogen bonds
bonds are weak but stick together in a lattice

Question 16

how does water have surface tension?

Answer 16

molecules on the surface of water are not effected by molecules above them so pull together more strongly

Question 17

why is cohesion and surface tension important for water?

Answer 17

so a body of an insect can be supported
to draw columns of water up xylem vessels

Question 18

how does water have thermal stability?

Answer 18

large bodies of water have fairly
constant temperatures

Question 19

how is having thermal stability important for water?

Answer 19

prevents large fluctuations in water temp so keeps aquatic habitats stable

Question 20

what happens when water freezes?

Answer 20

water expands as water molecules in ice form a rigid structure so there is more space in between them (less dense)

Question 21

how is freezing important for water?

Answer 21

ice floats on the top of water and is a good insulator for aquatic habitats

Question 22

how does water have a high specific heat capacity?

Answer 22

large amount of heat needed to raise its temperature because the hydrogen bonds between water molecules restrict their movement

Question 23

how does water have a high latent heat of vaporisation?

Answer 23

a lot of heat energy is needed to change it from a liquid to a vapour

Question 24

why is having a high latent heat of vaporisation important for water?

Answer 24

important in temperature control where heat is used to vaporise water from sweat on skin or from leaf surfaces