Answer:
Waldemar carried the recessive allele.
Explanation:
The carrier is the individual that has the affected allele or mutation but does not express the trait, or might express it in different levels. Although, as the person carries the mutation, she or he might transmit the genetic mutation associated with a disease to the progeny. In general, these diseases are inherited as recessive traits.
So, in the exposed example we know that:
- hemophilia is a sex-linked disorder
- hemophilia is determined by a recessive allele on the X chromosome.
- Irene is a carrier.
- Her husband is not a carrier.
- Her children Waldemar and Henry have hemophilia.
If Irene is a carrier, this means that she is heterozygous and that her genotype is X⁺X⁻ (Being the symbol + the dominant allele, and - the recessive one for that expresses the trait)
The fact that Irene´s husband is not a carrier means that his genotype is X⁺Y
Their boys Waldemar and Henry have hemophilia, so both their genotypes are X⁻Y
The best evidence to prove that Irene was heterozygous for hemophilia is that Alice carried the recessive allele.
- Alice is Irene´s Mother, and she is a carrier as well. Irene´s father, Louis, is not a carrier, so she could have inherited a dominant allele from her father and a recessive allele from her mother, X⁺X⁻, or she could have inherited two dominant alleles from both her parents X⁺X⁺. This is not proof enough of Irene being heterozygous.
- The fact that Alexandra, Irene´s sister, was also a carrier does not say anything about Irene´s genotype, because they could both share the same genotype or not. This is not proof of Irene being heterozygous.
- Frederick (her brother) was hemophilic. He received a recessive allele from Alice, but this does not say anything about Irene´s genotype.
- The fact that Waldemar (her son) was hemophilic, is the best evidence to prove that Irene was heterozygous for hemophilia. Walderman received the Y chromosome from his father and an X chromosome from his mother. The X chromosome that he received from his mother carried the recessive allele for the trait, and this is why he had hemophilia. This means that there is no best evidence for Irene´s genotype than her son´s genotype.
Answer:
C. Removing this step decreases the amount of carbon in the air: This is correct, removing factories would decrease the emission of greenhouse gases, thus decreasing CO2 in the atmosphere.
Explanation:
When we look at the picture we can see that the line that goes from G to C, goes from a factory to the atmosphere. As we know factories release a great number of elements into the atmosphere being one of them, carbon dioxide. Therefore taking into consideration we can proceed to analyze the following statements.
A. Removing this step prevents photosynthesis in the next step: This is not true industry increases carbon dioxide in the atmosphere, even if they don't exist there is enough CO2 for plants to perform photosynthesis.
B.Removing this step increases the amount of carbon in the soil: This is not true as factories release carbon dioxide to the atmosphere, not the soil.
C. Removing this step decreases the amount of carbon in the air: This is correct, removing factories would decrease the emission of greenhouse gases, thus decreasing CO2 in the atmosphere.
D. Removing this step increases carbon storage in plants: This is incorrect the carbon storage in plants is cording to their necessities independently of the abundance in CO2, in the atmosphere.
Explanation:
All living organisms need nutrients to survive. While plants can obtain nutrients from their roots and the energy molecules required for cellular function through the process of photosynthesis, animals obtain their nutrients by the consumption of other organisms. At the cellular level, the biological molecules necessary for animal function are amino acids, lipid molecules, nucleotides, and simple sugars. However, the food consumed consists of protein, fat, and complex carbohydrates. Animals must convert these macromolecules into the simple molecules required for maintaining cellular function. The conversion of the food consumed to the nutrients required is a multistep process involving digestion and absorption. During digestion, food particles are broken down to smaller components, which are later absorbed by the body. This happens by both physical means, such as chewing, and by chemical means.
One of the challenges in human nutrition is maintaining a balance between food intake, storage, and energy expenditure. Taking in more food energy than is used in activity leads to storage of the excess in the form of fat deposits. The rise in obesity and the resulting diseases like type 2 diabetes makes understanding the role of diet and nutrition in maintaining good health all the more important.
Answer:
conscious neural control
Explanation:
Neural control of digestive tract is unconscious achieved via the autonomic nervous system.
Local nervous system of the digestive system is called the enteric or intrinsic nervous system. The major components of this nervous system are two networks or plexuses of neurons:
• The myenteric plexus – controls digestive tract motility
• The submucous plexus - regulates gastrointestinal blood flow and controls epithelial cell function.
Explanation:
Reflexes do slow with age. Physical changes in nerve fibers slow the speed of conduction. And the parts of the brain involved in motor control lose cells over time.
Researchers found that the brain's response time begins to decline at age 24. The descent is a slow, but nonetheless, steady one.
