Answer:
A. Move substances down a concentration gradient
Explanation:
Active transport is the process of transport of substances in an energy dependent manner. The process of active transport requires energy to transport the substances against their concentration gradient. This means that active transport moves the substances from the region of their lower concentration to that of higher concentration.
<span>Brain is protected by bony skull and a liquid called the spinal fluid. The fluid acts as a cushion between brain and skull. It is a clear, colorless body fluid found in the brain and spinal cord. it is produced in the choroid plexuses of the ventricles of the brain, and absorbed in the arachnoid granulations.The spinal fluid occupies the subarachnoid space (between the arachnoid mater and the pia meter) and the ventricular system around and inside the brain and spinal cord.</span>
<span>This statement is false. The binomial nomenclature system was used to classify animals, but not until the 1700s when it was first formally introduced by Carl Linnaeus. In ancient times, plants and animals were instead usually just classified in terms of whether or not they were useful, or divided animals into categories such as 'domestic animals, wild animals, creeping animals, flying animals, sea animals'.</span><span />
Answer:
Explanation:
surface tension decreases when temperature increases because cohesive forces decrease with an increase of molecular thermal activity. The influence of the surrounding environment is due to the adhesive action liquid molecules have at the interface.
Answer:
97%
Explanation:
PKU is caused by a recessive mutation, which means that affected individuals are homozygous and recessive (<em>tt</em>).
<u>The frequency of genotypes according to Hardy-Weinberg equilibrium is:</u>
where p is the frequency of the <em>T</em> allele and q is the frequency of the <em>t</em> allele.
Affected individuals are 1 in 4500, which means the frequency of <em>tt </em>genotype is 1/4500.
If the population is in Hardy-Weinberg equilibrium,
The sum of the allele frequencies adds up to 1, therefore:
p + q = 1
p= 1 - q
p= 1 - 0.015
p= 0.985
The frequency of the TT genotype (homozygous wild-type individuals) will be:
97% of the population will have the homozygous wild-type TT genotype.
