Compare the functioning of alveoli in the lungs and nephrons in the kidneys with respect to their structure and functioning.
ALVEOLI |
NEPHRONS |
Alveoli are the tiny air sacs made up of squamous epithelium, which are present in the lungs for the exchange of gases. |
Nephron is the structural and the functional unit in the kidney and has elongated tubule like structure helps in the excretion process. |
It has thin wall for the exchange of gases – carbon dioxide and the oxygen. |
It is composed of Bowman’s capsule, distal and proximal convoluted tubule and the Loop of Henle for the excretion process by crossing the collecting duct and ejection of waste material occurs through the urethra. |
Numerous alveoli in the lungs show the maximum area for the exchange of gases between the air in the alveoli and into the blood in their surrounding capillaries and diffusion of oxygen occurs through this way. |
Nephron regulates the fluid balance or the water balance by eliminating the excess water from the blood by converting them into the urine. So, balancing of fluid regulates the blood pressure. |
Alveoli balance the carbon dioxide and the oxygen ratio. Oxygen goes from the lungs to the bloodstream and carbon dioxide gets eliminated from the bloodstream to the lungs through the capillaries which are located in the wall of the alveoli. |
By eliminating the acidic substances, excess water, minerals and salts and the nitrogenous waste from the blood; this maintain the volume, composition, pH and the osmotic pressure of the body fluids known as fluid homeostasis. |
Gaseous exchange in the alveoli is a passive diffusion process across the surface. |
Excretion is also a passive process primarily and secretion is an active process. |
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
How is the amount of urine produced regulated?
What criteria do we use to decide whether something is alive?
What are the different ways in which glucose is oxidised to provide energy in various organisms?
The breakdown of pyruvate to give carbon dioxide, water and energy takes place in
(a) cytoplasm. (c) chloroplast.
(b) mitochondria. (d) nucleus.
What are the differences between autotrophic nutrition and heterotrophic nutrition?
What are outside raw materials used for by an organism?
What would be the consequences of a deficiency of haemoglobin in our bodies?
What are the components of the transport system in highly organised plants?
What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What changes can you make in your habits to become more environment-friendly?
What is the difference between a reflex action and walking?
What is the importance of DNA copying in reproduction?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why do you think that there should be equitable distribution of resources? What forces would be working against an equitable distribution of our resources?
In evolutionary terms, we have more in common with
(a) a Chinese school-boy.
(b) a chimpanzee.
(c) a spider.
(d) a bacterium.
Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.
Name a mirror that can give an erect and enlarged image of an object.
Find out, from Table 10.3, the medium having highest optical density. Also find the medium with lowest optical density.
Material medium |
Refractive index |
Material medium |
Refractive index |
Air | 1.0003 | Canada Balsam |
1.53 |
Ice | 1.31 | ||
Water | 1.33 | Rock salt | 1.54 |
Alcohol | 1.36 | ||
Kerosene | 1.44 | Carbon disulphide |
1.63 |
Fused quartz |
1.46 | ||
Turpentine oil |
1.47 | Ruby | 1.71 |
Benzene | 1.50 | Sapphire | 1.77 |
Crown glass |
1.52 | Diamond | 2.42 |
Table 10.3 Absolute refractive index of some material media
Can any source of energy be pollution-free? Why or why not?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
How do auxins promote the growth of a tendril around a support?
Give an example of a double displacement reaction other than the one given in activity 1.10.