Many scientific studies of dietary health effects are observational. Compared to experimental studies, observational studies can extend over a longer time period, use a more representative population, and measure disease outcomes in addition to risk factors for disease. In an observational study, researchers enlist a study group, and use questionnaires and medical tests to quantify participants' health behaviors and status at the start of the study. The researchers continue to collect data on the participants over many years. Information about each particpant's diet, lifestyle habits, risk factors, and disease outcomes are all recorded and analyzed. A landmark study of this type -- called the Nurses' Health Study -- was begun in 1976 with more than 120,000 female nurses. Data from a subset of this group (80,082 women) was used to study dietary fat intake from 1980 to 1994. One goal of that study was to measure the effect of dietary trans fats on cardiovascular health. Do you understand how the Nurses Health observational study of dietary fats was set up and carried out? Sort the statements into the appropriate bins depending on whether they represent factors that varied from participant to participant at the start of this study, factors that were consistent from the start of the study, and factors that were measured in the study.

there is no

explanation:

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.

answer >   yes we do, women; have three holes, urethral opening(pee hole, vagina, and the women pee/girls pee out of the urethra like the men do; only they have a single opening to pee/ejaculate.   (sorry if i'm too forward with this, but this is for a biology class, isn't it? )

hope that !         : )