The folds in the stomach lining are called rugae. On these rugae, you will find a thin line of mucous which helps protect the stomach lining. The innermost layer is called Simple Columnar Epithelium.
Answer:
A glance of earth taken from space will depict it blue. This blue colour is actually water, the major part of the earth is covered with water. We need water for almost everything, for example- drinking, bathing, cooking etc and therefore we should know about the properties of water. 65 % human body is composed of water. Water is essential for the survival of life on earth. Water is distributed unevenly on the earth’s surface. It forms a major solvent and dissolves almost every polar solute. So let us have a look at its properties.
Physical properties of water : Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature
Chemical properties of water: Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water.
Explanation:
No muscle contraction will be observed.
<h3>What is the effect of calcium concentration on muscle contraction?</h3>
The concentration of calcium ions in the muscle cells help in contraction and relaxation of muscles fibers.
Release of calcium ions initiate muscle contraction.
Therefore, there will be no contraction of muscle if calcium ions are not transported out from the sarcoplasm.
Learn more about muscle contraction and calcium ions at: brainly.com/question/14760686
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These unsegmented worms have a full digestive system even when parasitic.
Answer:
Groups 4 to 7 are most likely to be undergoing the mitotic phase of the cell cycle.
Explanation:
Since the four proteins used p16, p18, p21, and p27 are inhibitors of cyclin-dependent kinases (CDK), their absence indicates that the cell is undergoing mitosis - the cell cycle is regulated by CDKs. In the absence of these inhibitors, the cell cycle moves on forward. Because the bar for DNA replication is longer in the case for groups 4 to 7, it is indicative of the fact that these cells have gone through the mitotic phase.
Hope that answers the question, have a great day!
