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In the diagram below, which letter indicates the part of the cell that carries out a function most similar to a function of the human excretory system?
The nucleus of a cell coordinates processes and activities that take place in the cell. Which two systems perform a similar function in the human body?*
Base your answers to questions 3 on the diagram below and your knowledge of biology. The diagram represents an ameba, a single-celled organism, carrying out an essential life process.
Which two body systems allow humans to carry out the same life process as the ameba in the diagram?*
The diagram below represents a process that occurs in human systems.
This process is known as*
Base your answers to questions 5 on the diagrams below and on your knowledge of biology. The diagrams represent some of the systems that make up the human body.
Which row in the chart below correctly identifies the main function of these systems?
An individual eats a hamburger. Which two systems must interact to transfer the nutrients in the hamburger to human muscle tissue?*
The kidney is an organ that collects wastes and excess water from the blood and sends them to the bladder where they are stored before being removed from the body. Which two systems work together to perform this function?*
The list below includes three organ systems that are directly used when a human runs.
circulatory system muscular system skeletal system
Which system should also be included in the list?*
Although the digestive system is primarily responsible for the breakdown of food, this process can be disrupted if the circulatory system malfunctions. The best explanation for this disruption is that*
Which life function is not necessary for an individual organism to stay alive?*
White blood cells are most closely associated with which two body systems?*
Select one row in the chart below and explain how the systems in that row work together during exercise. 
Base your answer to question 13-16 on the information below and on your knowledge of biology.
It is estimated that every year more than 15 million babies are born too early. The lungs of these premature infants are often immature and easily damaged. Premature births happen for a variety of reasons—some known and some unknown. Those that are known include infections and conditions such as diabetes and high blood pressure. Scientists are researching what causes premature births, in an attempt to develop solutions to prevent them.
Scientists are also working on the development of an artificial placenta. At the University of Michigan, five premature lambs were placed in artificial placentas and kept alive for weeks. During this time, each lamb’s blood was circulated through its artificial placenta.
Discuss how the development of an artificial placenta is an important step in the study of premature births. In your answer, be sure to:
• explain why it would be harmful for a human mother’s blood to pass across the placenta and into the
• state how an artificial placenta would be of benefit to the lungs of premature infants 
• explain why the lambs’ blood must be filtered as it circulates through the artificial placenta 
• state one reason why premature lambs were likely used as model organisms in this study rather than
Base your answers to questions 17 on the information below and on your knowledge of biology.
Mitochondrial Replacement Therapy
Mutations in mitochondrial DNA (mtDNA) are associated with some severe human diseases and are inherited through the cytoplasm in the egg cell. These diseases vary, but often affect organs and tissues with the highest energy requirements, including the brain, heart, muscle, pancreas, and kidney.
Scientists have successfully used mitochondrial replacement therapy with monkeys. Scientists are considering using this technique to reduce the incidence of mitochondrial disease in children. The proposed treatment would involve removing the nucleus from an egg donated by a healthy woman and replacing it with an egg nucleus from a patient (mother) with mitochondrial disease. This would place the patient’s egg nucleus into the cytoplasm of the donor’s egg containing healthy mitochondria. The egg is then fertilized with the father’s sperm externally using in vitro fertilization (IVF) to produce a zygote. The zygote is cultured for a few days to produce an embryo.
State one reason why muscle tissues are likely to be affected by mitochondrial diseases. *
Base your answers to questions 18 on the passage below and on your knowledge of biology.
Smoking is Dumb
A study by Prof. Mark Weiner of Tel Aviv University’s Department of Psychiatry and the Sheba Medical Center of Tel Hashomer Hospital has determined that young men who smoke are likely to have lower IQs than their nonsmoking peers. Tracking 18- to 21-year- old men enlisted in the Israeli army in the largest study of its kind, he has been able to demonstrate an important connection between the number of cigarettes young males smoke and their IQ.
The average IQ for a nonsmoker was about 101, while the smokers’ average was more than seven IQ points lower at about 94, the study determined. The IQs of young men who smoked more than a pack a day were lower still, at about 90. An IQ score in a healthy population of such young men, with no mental disorders, falls within the range of 84 to 116.
Source: Science Daily April 2, 2010
Explain how chemicals present in cigarette smoke are able to enter the body and reach the brain. *