Pasteur produced a nutrient broth and placed equal amounts of it in two long necked flasks. One flask had a straight neck (control) and the other had a swan shaped bent neck (being tested). He boiled the broth in both the flasks to kill any living organism that might be surviving on it. The two flasks were then left in the open air of the room to cool down. After several days passed, Pasteur noticed that the broth in the straight necked flask had changed its color but the swan necked flask didn't. From this observation he was able to conclude that the straight necked flask had let the organisms enter the flask and contaminate the broth. The swan necked flask blocked the entry of the organisms from the open air and thus remained unaffected.
Answer:
Community
Explanation:
A community is all the biotic factors of an ecosystem. There are many populations of different species within an area. These populations in one area is a community. A community and its abiotic features is a ecosystem. Therefore, communities have the most individuals in an ecosystem.
Answer:
1= In living organisms cells are composed of water or we can say that water is one of the important constituent of cells.
2= Hydrogen bonding import man properties to the water such as cohesion, high heat of vaporization, high heat capacity etc.
3= Because of high polarity, all polar substance get dissolve and make it universal solvent.
Explanation:
Solvent is the that part of solution which is present in large proportion and have ability to dissolve the solute. In simplest form it is something in which other substance get dissolve. The most widely used solvent is water, other examples are toluene, acetone, ethanol, chloroform etc.
Water is called universal solvent because of high polarity all polar substance are dissolve in it. Hydrogen is less electronegative while oxygen is more electronegative and because of difference in electronegativity hydrogen carry the partial positive charge while oxygen carry partial negative charge.
Hydrogen bond:
The hydrogen bond is the attraction between the toms which already take part in the other chemical bons. The one atom is hydrogen while other may be oxygen, nitrogen or fluorine.
The hydrogen bonding in water import man y properties in it such cohesion, high heat of vaporization, high heat capacity etc. The hydrogen bond hold the water molecules together.
Water create electrostatic interaction with other polar molecules. The negative end of water attract the positive end of polar molecules and positive end of water attract negative end of polar substance and in this way polar substance get dissolve in it.
Example:
when we stir the sodium chloride into water the cation Na⁺ ions are surrounded by the negative end of water i.e oxygen and anion Cl⁻ is surrounded by the positive end of water i.e hydrogen and in this way all salt is get dissolved.
Answer:
STM is capable of storing information for 10–15 seconds without rehearsal while working memory actively processes, manipulates, and controls the information. Information from STM can then be consolidated into long-term memory where memories can last a lifetime.
Explanation:
