Answer:
Parabolic dunes
Explanation:
A parabolic dune is a U-shaped mound of sand. The tips point upwind because they are anchored by vegetation.
A is wrong. The tips of a barchan dune point downwind
C is wrong. A longitudinal dune is parallel to the prevailing wind.
D is wrong. The ridge of a transverse dune is perpendicular to the prevailing wind.
It generally increases algae growth as nutrients are circulated up from the floor of the ocean.
Answer:
The correct answer is option A. "The contents of blood come into closer contact with tissues in a closed system than an open system".
Explanation:
In a closed circulatory system, the blood has an specific path, circulating from arteries to veins and to smaller blood vessels throughout the body. This is in contrast with open circulatory systems at which the blood is not contained in arteries or veins but it suffuses the body. A closed circulatory system have many advantages over open circulatory system, however in a closed circulatory system the contents of blood are not into closer contact with tissues in than an open system. Actually, in an open circulatory system the blood is in closer contact with tissues.
Answer:
Mutations rarely occur
Explanation:
Mutations are genetic changes, i.e., alterations in the DNA sequence. Generally, mutations have deleterious effects, but there are exceptions where mutations may confer an adaptive advantage in a given environment. Mutations are often deleterious, and thereby these genetic changes are rare events. In consequence, mutation rates, i.e., the frequency by which new mutations arise in an organism over time, are generally very low. Finally, mutations that arise only in germ cells can be inherited from a generation to the next generation, while somatic mutations cannot be inherited.
Assuming Hardy-Weinberg equilbrium, we have
p + q = 1
where p = frequency of dominant allele and q = frequency of recessive allele. So
p = 1 - q = 1 - 0.04 = 0.96
Consequently we have
• p² = 0.9216 = frequency of hom ozygous domininant genotype
• pq = 0.0768 = frequency of heterozygous genotype
• q² = 0.0016 = frequency of hom ozygous recessive genotype
since
p² + 2pq + q² = 1
