Answer: Women are carriers for the disease hemophilia because hemophilia is an X-linked disease. The recessive allele for the disease is found on the X chromosome.
The sons of carrier women get hemophilia because males have one X chromosome and one Y chromosome. The sons of a carrier woman may inherit the affected X chromosome from their mother, and a Y chromosome from their father. They have only one X chromosome and one it's affected, will result in hemophilia.
Explanation: Women are carriers because in most cases, only one of their two X chromosomes are affected. The two female X chromosome is rarely affected.
Daughters of carrier women will not get the disease because they need two affected X chromosomes to manifest the disease. So even if they inherit one affected X chromosome from their mother, the second X chromosome they will inherit from their father will be normal. Therefore, daughters of carrier women can only be carriers.
Answer:
The most important reason for learning about environmental systems is due to the fact that we should know what's going on in the world around us. If we were to travel to Asia, we should know the forests that lie there to pack appropriately. It's also important to just be aware of how the world works. It's also good to know what rock type you'll be walking on, so you can pack shoes accordingly. Overall, it's better to know the world around you than to live in ignorance.
Humans are called heterotrophs
Answer:
The answer is "form only at boundaries between two continental plates." :)
Question:All known organisms use genetic information to produce protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.
a) the earliest macromolecules probably arose when lightning struck an oxygen-free atmosphere
b) all organisms are descended from one or a few common ancestors
c) the genetic code readily evolves by natural selection
d) there's only one possible way to encode information in a macromolecule
Answer:
b) all organisms are descended from one or a few common ancestors
Explanation:
Protein synthesis occurs when the nucleotide sequence of the mRNA is read in the form of genetic codes. A specific genetic code specifies the same amino acid in all living beings. For example, the code "UUU" codes for phenylalanine in all the living beings irrespective of their species. This suggests that all the life forms have originated from one or few common ancestors and the genetic code has been preserved during the course of evolution of various species.
