Answer:
The correct answer is - D. All rocks were molten in that time period.
Explanation:
The early Precambrian era began 4.6 billion years ago. The formation of eath start from this era with dust and gas. The atmosphere at that time was too hot. It was like hades. The rocks were molten and appear to like an ocean of rocks.
Due to the molten rocks, there are no samples of rock from this area as it was too hot to be formed. There were boiling sulfur and gases were everywhere.
Rigid skeletons are formed from materials including chitin (in arthropods), calcium compounds such as calcium carbonate (in stony corals and mollusks) and silicate (for diatoms and radiolarians).
Answer:
Option-D
Explanation:
In the given question the genotype of parental allele is- AbaB X AbaB. The alleles formed will be- AB, Ab,aB, ab in which the crossover allele will be AB and ab.
1. Unlinked genes
Now of these alleles are unlinked then the alleles will assort independently of each other therefore performing the punnett square we will get dihybrid ratio as 9:3:3:1 in which
1. A_B_ are 9
2. aaB_ are 3
3. A_bb are-3
4. aabb- 1
Since the crossover allele are AB and ab therefore A_B_ are 9 and aabb- 1 represent recombinant genotype.
2. Linked genes
When the genes will be linked then chances of crossing over will be reduced as a result of which only two type of allele will be formed which are- Ab and aB and the recombinant frequency will become less.
Crossing these allele will form Aabb
, AaBb
, AaBb and aaBB genotypes.
The recombinant ratio will decrease as A_B_ is 2 and aabb is not present.
Thus, option-4 which states that the unlinked ration is 9:3:3:1 and linked ratio is <9: >3: >3: <1 is correct.
Answer:
Plasmin
Explanation:
Plasmin is a serine protease also referred to as fibrin digesting enzyme, it is responsible for the dissolving or degradation of blood clot. The process by which plasmin degrades blood clot is called fibrinolysis. Note that plasmin (active) is formed from an inactive enzyme called plasminogen.
Answer:
Water cycle
Explanation:
Water rains from the cloud into the ocean. Then the water gets sucked back up to atmosphere of the clouds