a1.1 water Flashcards
what are the four reasons why water is important
- water is a solvent
- is a metabolite
- provides optimum temp for enzymes
- maintains biological structures
importance of water as solvent
has ability to dissolve molecules thus transport them around organisms acting as a medium in which chemical reactions happen in
explain importance of water as a metabolite
in chemical reactions in cells water either is the reactant or product
condensation- water product
hydrolysis- water reactant
explain importance of water providing optimum ph
in metabolic reactions which uses enzymes, they need optimum temperatures which water provides
water has a high specific heat capacity thus can stay liquid for long
explain importance of water maintaining biological structures
contributes to formation of cell membrane (phospholipid heads interact with water, phospholipid tail avoids water, this makes protein fold into shape needed to perform function)
surrounds DNA to support double helix (needed to follow instructions encoded DNA or pass instructions into future cells)
how did the solar system form
when a cloud of gas and dust collapsed into a swirling disk; some of the cloud was water
chemicals- water
functions as solvent allowing key chemical reactions to take place,
heat conduction,
surface tension and
high specific heat capacity
chemicals carbon-
simple building blocks that organisms need to form organic compunds
chemicals- phosphorus
key component of ATP molecule, providing energy to drive ans support many processes in living cells
chemicals- nitrogen
needed to make amino acids
chemicals- sulphur
part of many biochemical processes on earth most enzymes cant function without
what 2 characteristics support retention fo water
distance of earth from sun keeps temp below water vaproisation, water is able to stay liquid or ice from due to cohesion of water molecules via h2 bonds
earths gravity keeps water from escaping planet
name of bond between O and H
polar covalent bonds
charges of o and H
O= -
H= +
are water molecules polar or non polar
polar
polar meaning
hydrophilic molecule
water loving
non molar meaning
hydrophobic molecule
water fear
name of bond between different H2) molecules
hydrogen bonding
how many bonds can a single H2O bond possess with other H2O molecules
4
definition of cohesion
attraction between water molecules
force by which individual water molecules stick together through hydrogen bonding
definition of adhesion
attraction of water molecules and another very thin surface
force by which individual water molecules stick to surrounding ionic or polar molecules through hydrogen bonding this allows water molecules to associate to soil particles and diffuse to the roots of plants by osmosis
defenition of thermal (property of water)
1- high thermal conductivity water conducts transfers and absorbs heat
2- high specific heat capacity (water needs a lot of energy to change its temperature because of meany h2 bonds which must be broken)
solvent defenition ( water property)
water is the universal solvent due to its polarity
definition of viscosity ( property of water)
measure to resistance of a fluid to flow water has a higher tendency to reduce flow whn it has solutes dissolved on it than air
defenition of buoyency ( property of water)
objects that are denser than water will sink while objects that are less dense than water will float
examples of cohesion organisms exploit of property
surface tension- results from great attraction of water molecules to each other (cohesion)
fishing spiders ad water striders rely on surface tension to move across surface
surface tension stronger than force of gravity pulling down
examples of adhesion organisms exploit of property
allows capillary action movement of water through thin tube without assistance or opposition of external forces helps move water up thin xylem vessels inside stem
examples of thermal conductivity organisms exploit of property
thick layer of fat provies insulation from cold ocean temp in marine animals
water in blood carrying heat generated at contracting muscles to skin where it lost from body (thermoregulation) body changes blood supply in response to change in activity
water rapidly conducts body heat away from the body becomes hypothermic more quickly in water than air
examples of high specific heat capacity organisms exploit of property
important to maintain stable internal and external environment helps body temp rise and fall slowly when temp changes
examples of solvent organisms exploit of property
water being able to dissolve polar or ionic substances solutes whenever water goes eg. ground or body takes along valuable chemicals nutrients minerals
water, proteins, nutreints, enzymes, salts, metabolites, hormones are all able to dissolve in blood/water in body
examples of viscosity organisms exploit of property
formation of hydrogen bonds reduce waters tendency to flow water can dissolve many solutes which increase viscosity of blood
waters low viscosity makes easy for organisms to move through it aquatic life, allows swimming allows efficient transfer of nutrients and o2 throughout body of aquatic organism
examples of buyouncy organisms exploit of property
bony fish change their denisty by changing size of swim bladder filling with gases or not thus able to move up or down in water\birds main limb bonws are hollow with struts inside to strengthen them and making it less dense to bloat in water
surface tension
water moelcules on the surface are more attracted to each other, cohesion, than they are to molecules in the air. the net effect is an inward force at the surface that provides a habitat for some organisms eg. mosquito larvae to live on.
capillary action
movement of water molecules (cohesion) throguh a thin capillary tube adhesion without the assistance of or even in opposition to any external force like gravity this allows the movement of water up the xylem vessles in plants as water molecules stick to cellulose
black throated loon adaptations for buoyancy
hollow bones (main limbe bones) with struts inside to strengthen them and make less dense thus float on water
black throated loon adaptations for viscosity
webbed feet and streamlined body shape which overcome viscosity of water
black throated loon adaptations for thermal conductivity
oil gland near their tail use beaks to rub oil over feathers and make waterproof
black throated loon adaptations for specific heat capcity
oil gland near their tail use beaks to rub oil over feathers and make waterproof
ringed seal adaptations for buoyancy
changes position stays in back which increases surface area
ringed seal adaptations for viscosity
streamlined body shape and paddle like feet overcome viscosity of water
ringed seal adaptations for thermal conductivity
ringed seal adaptations for specific heat capacity
thick blubber under their skin for insulation reduces heat loss from seals internal organs
when water freezes seal changes habitat goes into ice caps or immigrates for food
what properties explain why water makes a good solvent
polaritty of water molecules
high specific heat capacity of water
in regard to water molecules where do hydrogen bonds form
between different water molecules between the positevly charged hydrogen atom and negatively charged oxygen atom
define specific heat capacity
measure of how easily heat flows through materials
the specific heat capacity of air is lower than water so air temperatures
fluctuates
as water has a higher speicific heat capacity water provides a
much more stable enviornment for the seal
how did the solar system form
when a cloud of gas and dust collapsed into a swirling disk; some of the cloud was water
why liquid water could not be found in early inner solar system
young sun intense heat prevented water vapour from condensing
what is the main hypothesis for origin of water on earth
tiny grains of dust acted as condensation nuclei, let droplets form particles coalesced into young planet along with water carried when earth cooled rocks in crust reacted with chemicals in earths atmosphere to create more water molecules; water existed inside earth mantle but not as individual h2o molecules but as oh or simply h
most of water was imported from asteroids or comets, believed that jupiter was closer to the sun and its gravity caused millions of asteroids to be pushed towards earth
what is evidence that asteroids and comets provided water to earth
every h2o molecule, a fraction of it has a hydrogen atom which has an extra neutron in nucleus
water from a comet vs asteroid has different ratios of these heavy hydrogen atoms and when comparing this with normal water, the waters atomic fingerprint is more closely related to that of an asteroid thus majority of water came from asteroids not comets
what does goldilock zone mean
habitable zone where it has just right distance from a star for water to remain at least periodically in loquid form on surface, earth orbits sun just right distance for water to remain lqiuid thus in goldilock zone
explain mars relationship to goldilock zone
mars is in the goldilock zone however it is too small to keep an atmosphere which is needed to sustain life
what are the circumstances for life to be present in a planet
luck- having all right chemicals at same place same time
time- evolution is complex took billions of years
location- not too hot or too cold to have liquid water on surface
name of equipment that explores planet surface
rover
location on earth with similiar H:N ratio as asteroids
oceans
