The Role of Water in Ensuring Processes of

Living

Laima Ozoliņa

Riga Secondary Night (Shift) School No.14

The Role of Water:

• Molecular level• Cellular and organism level• Water- setting for life• Water- regulator of a climate• Water and people

Water can be found in three states of aggregation:• as a hard state (e.g. ice),• as a liquid state (e.g. water),• gaseous state (e.g. water vapor or steam)

Hydrosphere (greek: ὑδρο-, hydro- — ‘water’, σφαῖρα, sphaĩra — ‘sphere’) is one of the Earth’s covers, which is made out of water that can be found in oceans, sees, above earth’s surface (lakes, rivers, swamps and other inland waters) and below the surface

(groudwater). Water covers ~75% of the Earth’s surface. Its gross mass is ~1,4×1018 tonnes, which is 0,023% from the Earth’s.

Approximately 2×1013 tonnes of water, mainly as a vapour, are ir the atmosphere.

Chemical and physical properties

• Water is a good polar solvent.• Water has great thermal capacity (slowly heats up and slowly

cools down). • Water has a unique density change when temperature falls

down or freezes. • The density of water increases up to + 4 o C (maximum

density), but from + 4 o– 0 o C density decreases. Ice (crystallline water) is lighter than liquid water. This way density facilitates its circulation below ice and O 2 delivery to all the living in water.

Molecule of water

Chemical formula: H2O

Molecular mass:18,01528 g/mol

Density:1000 kg/m3

Melting: 0 °C (273,15 K)

Simmer: 100 °C (373,15 K )

Water is the basis for all living, that is why, it could be considered to be the most important liquid in the world.

It is said that all known living forms need water , as well as that the life has begun in the water.

• Takes part at photosynthesis.

• Provides transport for different substabces.

• In nature it is a habitat for water creatures.

• With the help of water impregnation (for non-seed plants, spore plants, animals with external impregnation) and development of fetus is possible.

• Provides osmoregulation and un turgor pressure for plants.

• Helps plants with circulation of different substances with a help of transpiration.

• Takes part in cutting biopolymer molecules (hydrolisis).

Physiological importance

Water is a raw material for photosyntesis

• Photosyntesis is one of the most important processes in nature used by plants and other organisms to convert the light energy captured from the sun into chemical energy that can be used to fuel the organism's activities. Moreover, during photosyntesis oxygen, that all aerob organisms use for breathing, is exuded. Photosyntesis provides that substances and matters circulate in nature and the balance of gases in the atmosphere.

• 6CO2+ 6H2O → C6H12O6+ 6O2

Water in organisms

• All living organisms contain70 % – 90 % water and that ensures the existence of the living.

• Water sustains balance in the body (homeostasis).

• Ensures absorption in cells, provides transport for substabces and matters to particular cells and getting metabilic waste products from the organism.

• Provision of terrestiral water depends on: air humidity, precipitation, water in soil, closeness of lowground waters, water’s course etc.

Water- natural habitat

Almost all living creatures for their metabolic processes need water. For many of them, water is the natural habitat. The adequacy and consistency of it depends on the chemical composotion of different salts, distribution of temperatures, sea currents, profundity and pollution.

• The most organisms in the ocean are located in the light zone (up to 200 meters), where sunshine hits them. A lot of seeweed is located there and it provides organisms living in water with necessary food and oxygen.

• When going deeper in the ocean the light and organisms decrease. In the twilight zone (200 – 1000m) whales and wild fish are located, for example, sharks and ray – fish, but on the seabed you can find echinodermata and slugs. Spreading of the organisms in deeper water is limited by not only not enough light, but also colder water temperature and higher pressure.

• Small amount of organisms are located in the dark zone (1000 – 4000m) and only small amount of plants can survive deeper than 4000 meters . Deepest zone where fish has been caught is 8000 meters.

• Water on Earth can be found in different forms – in the sky as clouds, in saltwater and in forms of icebergs, in lakes and rivers, etc..

• Water circulates in the World through vapour and rain. Vapour that can be found in atmosphere creates clouds by condesating.

Water- regulator of a climate

The Hydrologic Cycle

• Due to effects of climate change summers are becoming increasingly hotter, affecting human and animal health as well.

• By the start of grazing season animals are affected by the stress caused with heat and increased insect attacks.

• Sensitive to the high heat are both agricultural and domestic animals.

• A peripheral vasodilatation can occur for animals who stay long at elevated temperatures and without any increase in circulating blood’s volume, the death of an animal can follow as a result.

• Newest trends suggest that climate changes have contributed to emerging and spreading of animals’ diseases. Animals can suffer from celiac disease, vector-borne diseases, have heat strokes or become dehydrateded and fell dehydration. The biggest problem is the high heat and climate changes in the migration area for animal movements.

Water- regulator of a climate

In the world altogether for the needs of householding, pets, recreation and production is consumed 565 km ³ of water per year. Irrigation related to food production requires another 3300 km ³. Taken together, it is about 4,000 km ³ of water per year, which corresponds to 44% of the actively circulating water’s quantity.

Water and people

A great percentage of our body consists out of water (e.g. newborns =75 %, grown-ups = 60%).

In order to keep living a human needs to drink app. 1-2 l of waterper day, excluding that they receive from food.

• Human body cells live in an intracellular fluid (for an adult the amount of the fluid is 50 liters), which is in constant motion. From this liquid cells are feeding, acquiring oxygen and excreting metabolic end products that further with the help of the lymph are drained to veins and excreted from the body. The faster this process occurs, the faster the body disposes of waste products.

• Elimination is even more important than substance intake in order for cells to be intact and free from diseases, since each cell has to eat, work and discharge waste that can be removed only with water.

• When a child is born 90% of his/her weight is the water.For an adult this number is 75%, but the old man has just 65% of water in his/her organism. With years, we'' dry out'' and become like raisins.

Water and health

What happens with an organism if it does not have enough water?

•  1% - if your organism has lost such amount of water – you feel thirsty. If the weight of a person is 100 kg, it can be calculated that a person has lost 0,7 l of water, because 70 % a human’s body is made out of water.

•  2% - loss of appetite, stress and reduced capacity of work.

•  4% - sickness, tiredness, headaches and emotional instability.

•  6% - disorders of coordination and speech.

•  10% - problems with thermoregulation and un cells start to die.

Thank you for attention!

Bibliography: http://www.ploome.com/lat/pareizs-uzturs/udens.html http://www.llkc.lv/?id=401314 http://www.medusmaize.lv/index.php?

option=com_content&view=article&id=14&Itemid=18&lang=lv http://b1v.lv/wp-content/files/biologija_11/

default.aspx@tabid=9&id=320.html http://scotthull.com/artists/smith/# http://scotthull.com/artists/smith/files/2010/10/

WaterCirculationGeoffSmith.jpg