Answer:
A
Explanation:
Living organisms adapt to their moves and positions in response to the environmental changes for their protection or to their advantage. When an entity reacts to the changes in its surroundings, it is referred to as stimulus while the reaction to the stimulus is referred to as a response. Common stimuli are sound, light, air, heat, smell, taste, water and gravity.
Think of burning your finger of fracturing your bone without any pain sensation. It may certainly sound like a superpower or an ideal situation, however, when it comes to the standpoint of survival, it can be disastrous.
It is a characteristic behaviour of living entities to respond to stimuli with the intervention of the Nervous System. It is an organ system ascribed to send signals from the spinal cord and the brain throughout the body and then back from all the body parts to the brain. Neuron acts as the mediator and is the basic signalling unit of the Nervous system.
Pain is the body’s way of letting us know that something is not right. It can prevent further injuries or push us to seek medical attention. Moreover, all of this is possible because humans can respond and react to stimuli due to control and coordination among the various organs and organ systems.
Control and Coordination in simple multicellular organisms take place through only the Nervous system which coordinates activities of our body. It is the control system for all our actions, thinking, and behaviour.
Answer:
<h2>Its true!!</h2>
Explanation:
Actually the haemoglobin molecule consists of 2 parts, the haem which is a prosthetic group and the other globin which is a protein. So the haemoglobin as is a protein so, is arranged in quaternary structure of protein which contains 4 subunits. The subunits depend upon the organism whose haemoglobin is being talked about. So the normal haemoglobin found in red blood cells contains 2 alpha subunits + 2 beta subunits. At the centre of each subunit there is the haem part attached. To the centre of haem the Fe3+ ion are present which actually attaches to 1 Oxygen molecule. So as 4 subunits are present and each subunit has 1 Fe3+ ion, so total 4 Oxygen molecules can bind to the 1 Hb molecule!!
The alveolus (singular form) or alveoli (plural
form) are tiny sacs of organs that are attached to the ends of the alveolar
duct. These tiny sacs of air are clumped together that form interconnected
caves, working together as a unit. They are found inside the lungs and they
make the exchange of air easy and possible. Alveoli units are responsible for
putting oxygen into the air that we breathe in. Blood that passes through the
heart and into the lungs are converted into oxygen which will be then
transported by the blood all over the body systems.
<span>
The walls of the alveoli are extremely thin to
enable the quick exchange of gases Aside from this, the linings of alveoli
units are fluid in nature enabling gases to dissolve. </span>
Answer:
All chemical reactions involve energy.Energy is used to break bonds inreactants, and energy is released when new bonds form in products. Endothermic reactions absorb energy, and exothermic reactions releaseenergy. The law of conservation ofenergy states that matter cannot be created or destroyed.
Karyotype helps to study the presence and location of genes on chromosome. This also helps to find the mutations such as duplication or deletions.