Answer:
The reflex arc follows this sequence of events
1. sensory receptor activation
2. sensory neuron activation
3.information processing
4. motor neuron activation
5. effector response
Explanation:
Reflex arc is the pathway of nerves during a reflex action. An example of a reflex arc is when we accidentally touch a hot object. First, the receptor in the skin detects a stimulus in this case the change in temperature. Second, the sensory neuron transmit the electrical impulses to the Central Nervous System for information processing. Then relay neurons connect sensory neurons to motor neurons. Third, motor neurons sends electrical impulses to an effector wherein the effector produces a response ( muscle contracts to move the hand away from the hot object. This happens in a split of seconds.
Answer:
Consumer Spending Declines
Explanation:
Answer:
It seems that a reciprocal translocation is going on.
Explanation:
A translocation occurs when a chromosomal fragment changes its location in the same chromosome from the original to a new one. Or when it leaves the chromosome to re-locate in a new different chromosome.
According to this, there are different types of translocations:
- Intrachromosomal translocations:
- Intra-radial: the change in position occurs in the same arm of the chromosome. For instance, 123.456789 → 123.478569
- Extra-radial: The change in position occurs from one arm to the other of the same chromosome. For instance, 123.456789 → 15623.4789
- Extrachromosomal translocations:
- Transposition: not reciprocal interchange. The fragment leaves a chromosome to re-locate in another chromosome. The other chromosome does not send any fragment to the first one.
- Reciprocal translocation: There is a reciprocal interchange. A fragment of chromosome A goes to B, and a fragment of chromosome B goes to A.
Reciprocal translocations might be:
- Fraternal: the interchange occurs among homologous chromosomes
- External: the interchange occurs among non-homologous chromosomes
Reciprocal translocations are easily recognized during meiosis because an association between four chromosomes can be observed. This association is a quadrivalent structure.
During metaphase 1, the centromeres involved in the quadrivalent originate centromeric co-orientation or disjunction.
Answer:
If an individual has a dominant phenotype it is not known what the exact genotype is. For example with the phenotype of brown eye color , the genotype could be heterozygous.
Explanation:
Dominant is a trait that shows dominance over a recessive trait. The dominant trait might have a heterozygous or homozygous genotype.
For example, if the brown eye is a dominant phenotype, it might be that a person might have a heterozygous genotype for this trait. One of the alleles might be the dominant one while the other allele might be recessive. In such a case, the effect of the recessive trait is masked by the dominant trait. Hence, the organism shows the dominant phenotype but has a heterozygous genotype.
