The 1883 eruption of Krakatoa (Indonesian: Krakatau ) in the Sunda Strait began on the afternoon of Sunday, 26 August 1883—with origins as early as May of that year—and peaked on the late morning of Monday, 27 August 1883, when over 70% of the island of Krakatoa and its surrounding archipelago were destroyed as it collapsed into a caldera.
Answer: 23
Explanation: One pair of the 23 chromosomes, known as sex chromosomes, determines at conception whether a fertilized egg will develop into a male or female. Today, human females have one pair of identical X chromosomes.
Answer:
Mutations leading to the better attachement of virus to the host cell would allow the virus to spread the infection and leave more progeny. The reproductive fitness of mutant viruses would allow the mutation to spread.
Explanation:
1. The organisms with same resource requirement compete with each other. Viruses are not living things but once inside the host cell, they behave like living things. Rapid multiplication of virus overpopulate the host cells.
2. Genetic variations are added to the viral progeny by random errors during replication of the viral genome. These random variations may impart beneficial trait, harmful feature or remain neutral. If a random mutation in the SARS-CoV2 virus allows it to adhere better to the cells of the respiratory system, the virus would be better able to infect these cells to spread the infection. Once inside the host cells, the mutant virus would leave more progeny. On the other hand, the wild type virus that lack this mutation would have lesser chances of entering the host cells and may or may not replicate.
3. The progeny of the mutant virus would compete better with the non mutant ones due to the presence of same mutation.
4. Differential reproduction and more progeny of the mutant virus would spread the mutation among the virus.
Answer:
Explanation: The body mass is a weight of the person. The total surface area of the air sacs means that in an organism who is having air sacs, spaces are present in them In these air sacs there is a presence of air which is constant.
Explanation:
The relationships between the ratios of Hemoglobin total surface area of such conditions result from the available amount of air sacs that permits.
Birds of 21 species with body mass ranging from 8 to 170 g, in eight species of antiracial.
Air sacs are present as small sacs off the bigger respiration tubes (tracheae) of insects, as prolongation of the lungs in birds, and as final organs in the lungs of certain other vertebrates.
They give to increase respiratory efficiency by giving a huge superficial area for gas transportation.
Answer:
C. Fossilized marine creatures can be found at the top of the Himalayan Mountains.
Explanation:
The scientific theory of plate tectonics tells you that when the plates collide they form different landforms such as mountains, pushing all the fossils and plants up with them.
