The correct answer is: A. minus end; dynein
Microtubules are cytoskeletal fibers that have an important role in the intracellular transport (movement of vesicles within the cell) and in the mitotic spindle during mitosis. The plus end of the microtubules extend through the periphery of the cells while the minus ends are anchored within the centrosome.
Necessary proteins for the vesicle’s movement are motor proteins:
• kinesin which is positive end directed
• dynein which is negative end directed
So, beside vesicles these proteins are also involved in organelles’ transport in opposite directions through the cytoplasm.
Answer:
D. magnetism, electrical conductivity, high melting point
Explanation:
Magnetism is the property of metal due to which they are attracted by magnets. Metals have high electrical conductivity which means they are good conductors of electricity. They also have high melting points i. e. they require high amount of heat to change its solid state into liquid state. In melting, bonds are broken down due to the applicable of heat energy.
Answer:
The salinity of water increases as you move from inland areas out towards to ocean.
Explanation:
Salinity refers to the concentration of salt in the water. The salinity of water increases as you move from inland areas out towards to ocean because the ocean has high salinity than the inland areas. That is it can be said that the ocean contains brackish water. Brackish water has more concentration of salt than freshwater.
Answer: After 3 rounds, 8 segments having 2 original strands on different segments will be present.
Explanation:
The polymerase chain reaction selectively and repeatedly copy the double stranded DNA (dsDNA) in the PCR machine.
1st round:
Single piece of double stranded DNA (dsDNA) unwinds in two seperate strands, before complementary nucleotides are synthesized to establish double helix.
2nd round:
The two dsDNA yields 4 segments before complementary nucleotides are synthesized
3rd round:
The four dsDNA yields 8 segments before complementary nucleotides are synthesized.
Therefore, at the end of 3 rounds, the two original strands will be present on the 8 different segments of copied DNA.
Stars begin to form from clouds of gas in space. The cold temperatures and high densities (compared to elsewhere in space, but would be considered a vacuum on Earth) of these clouds allow gravity to overcome thermal pressure and start the gravitational collapse that will form a star.
