Because the temperatures vary on high global temperatures and its economy.
Answer:
Mark pathogenic cells for destruction. (Ans. B)
Explanation:
Antibodies are generated by the plasma cells, and once these secreted, they attach quickly to the surface of the toxin and stop the toxin from infecting the normal body cell by blocking key extracellular sites.
Antibodies also help to mark pathogens for destruction by the help of macrophages or neutrophils and they are known as phagocytic cells because they are highly excited to macro-molecules complexed with antibodies.
Answer:
I think the answer would be Nearest the major highway
Explanation:
Answer:
- Fresh water fish have higher salt contents in their bodies than in their environments.
- Marine fishes have less salt in their bodies than their environment
- Terrestrial organisms have the challenge of water retention due to atmospheric contact.
Explanation:
FRESH WATER OSMOREGULATION
The salt concentration in salt water fish is higher than the concentration found in its environment (fresh water). This causes water to enter into the body of the fish through osmosis and without regulating processes, the fish is bound to swell and likely burst.To compensate for this challenge, the kidney in fresh water fish produces a large amount of urine, causing them to lose salt. To ensure too salt is not lost beyond the basic requirement, chloride cells in the gills take up ions from the water which are transported into the blood.
MARINE OSMOREGULATION
In marine fishes, the challenge opposes that of fresh water fishes since salt content in this case is lower in their blood than in their environment. To address this challenge, marine fishes lose water constantly while retaining salts to lead to a build up. The water lost, is then made up for and replenished by continual drinking of seawater. The chloride cells in marine fishes works in a manner opposing that of fresh water fish, functioning to compliment the excretion of salts by the kidney.
TERRESTRIAL OSMOREGULATION
The major challenge of osmoregulation in terrestrial organisms is water regulation in the body owing to their contact with the atmosphere.
Terrestrial organisms possess effective kidneys which enable osmoregulation. A series of processes including filtration, re-absorption and tubular secretion, enable regulation of fluids and water conservation.
Water passes out of the descending limb of the loop of Henle, leaving a more concentrated filtrate inside. Salt diffuses out from the lower, thin part of the ascending limb. In the upper, thick part of the ascending limb, salt is then actively transported into the interstitial fluid. The amount of salt in the interstitial fluid, determines how much water moves out of the descending limb i.e the saltier it gets, the more water moves out of the descending limb. This process leaves a concentrated filtrate inside, so more salt passes out. Water from the collecting ducts moves out by osmosis into this hypertonic interstitial fluid and is carried away by capillaries, achieving osmoregulation.
Answer no 8:
The correct option is D) Antelopes with muscular legs are bale to outrun their predators better than antelopes with poor muscle tone. Thus they lived to reproduce.
Explanation:
Genetic variations in a population are the main reason that natural selection tends to occur. Natural selection favours those organisms which have better characteristics.The organisms with better traits are able to reproduce and pass on their characteristics to their offsprings.
Answer No 10:
The correct option is A) Phenotype directly influences the interaction of an organism with its environment.
Explanation:
The interactions between the phenotypic traits and the environment analyze whether a particular organism will be able to survive and pass on its characteristics to its offspring. Hence, the phenotype directly influences the interaction of an organism with its environment.
Answer No 9
The correct option is A) resistance to a virus
Explanation:
Mutations can be described as any changes which occur in the DNA of an organism. Mutations might be beneficial or harmful depending on the location where the mutation arises. Viruses are usually harmful for eukaryotes. Hence, the correct option is A.
Answer No 11:
The correct option is C) Giraffes with longer necks survived because they were better suited to the environment.
Explanation:
Natural selection tends to favour those organsims which are better suited to live in an environment. Those organisms with better characteristics are able to survive and pass on their traits to their offsprings.
The giraffes with longer necks were better adapted to live in the environment and hence were favoured by natural selection.
Answer No 12:
The correct option is D) selective breeding
Explanation:
Selective breeding can be described as a technique in which organisms with better characteristics are crossed, so that offsprings with better characteristics can be produced. Selective breeding is done by humans where as natural selection is done by the nature.
