Answer:
B Physical separation of populations prevents interbreeding and mixing of gene pools.
Explanation:
Geographic isolation means two populations are unable to reproduce with one another. This means that over time, the variation in the gene pool will be different for one group compared to the other, and the species will genetically diverge from one another. resulting in speciation.
Answer:
Option 3, Chromatids remain attached to one another until anaphase
Explanation:
Centromere lies at the center, end or other points of the chromosome and joins the two sister chromatids. During cell division, the spindle fibers attaches at the centromere and detaches the chromosomes during the anaphase of the cell division to ensure that each daughter cell gets equal number of chromosomes at the end of mitosis. Centromere plays an essential role in the separation of chromosomes.
Hence, option 3 is correct
Answer:
Sedimentary rocks
Explanation: Where are fossils found? Fossils are found almost exclusively in sedimentary rocks—rocks that form when sand, silt, mud, and organic material settle out of water or air to form layers that are then compacted into rock. So the answer will be <em>Sedimentary</em> rocks.
<span>From the belief that clavicles- when exposed, e.g. in a topless dress or in a state of semi-nakedness or nakedness- make a woman or man look beautiful</span>
Answer:
Reflexes are not a function of the spinal cord.
Explanation:
The spinal cord is part of the central nervous system and is made up of neurons that go along it (from the end of the brain stem almost to the bottom of the spine).
The spinal cord receives incoming messages from the peripheral nervous system (including the sensory neurons) and pass on messages from the brain to efferent neurons (motor neurons at muscles).
The spinal cord contributes to learning as it passes on the info received from sensory neurons (that there is an obstacle in the path) to the brain and passes on the response from the brain to the muscles (to lift the foot up higher).
The spinal cord is essential for integration as it passes on sensory information to the brain to determine motor output.
Reflexes are when sensory information is quickly sent straight to motor neurons to move. It does not need to go to the brain (hence does not need to go to the spinal cord) for the reaction as it would be too slow. This is seen when someone who is paraplegic (paralysed at lower torso) can still move their leg in response to the doctor tapping their knee even when they cannot forcibly move their legs.
Therefore reflexes are not a function of the spinal cord.