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The reproductive cycle in females is regulated primarily by*
Base your answers to questions 2 on the graph below and on your knowledge of biology. The graph shows the number of species that have become extinct since 1800. It also shows the change in the size of the human population for the same period of time.
The rapid increase in human population between 1960 and 2010 is most likely the direct result of advances in*
Which factor is a major cause of the changes that occur during puberty, the years when the rate of human physical growth increases and reproductive maturity occurs?*
The photograph below shows two color variations of Himalayan rabbits. In the winter, the rabbits resemble the one on the left. In the summer, the rabbits resemble the one on the right.
The changes in fur color are most likely due to*
Exposure to certain environmental toxins, such as pesticides, may reduce fertility in males by interfering with their ability to produce gametes. These toxins are most likely having an effect on the*
The human female reproductive cycle is regulated primarily by the*
Testosterone directly affects the*
Base your answers to questions 8 on the graph below and on your knowledge of biology. The graph shows some events associated with the reproductive cycle of human females.
Which sections of the graph represent structures affected directly by the hormones shown?*
Populations of aspen trees in the western United States are being destroyed by an unexplained illness. The altered landscape is affecting the animals that live there. Populations of deer mice are increasing greatly in these areas. Unfortunately, these mice often carry a virus that is deadly to humans. This scenario best illustrates that*
Three human hormones most directly involved in sexual reproduction are*
Base your answer to question 11-13 on the information below and on your knowledge of biology.
The Critical Role of the Placenta
The proper functioning of the placenta is critical to the growth and development of a healthy fetus. For example, the placenta appears to act as a nutrient sensor. It regulates the amounts and types of nutrients that are transported from the mother to the fetus.
Improper functioning of the placenta can alter the structure and function of specific cells and organ systems in the developing fetus, putting it at risk for health problems as an adult. For example, in some pregnancies, the placenta develops a resistance to blood flow. This resistance appears to force the heart of the fetus to work harder. This could result in an increased chance of the individual developing heart disease as an adult. A group of hormones known as glucocorticoids affects the development of all the tissues and organ systems. One of the things this group of hormones does is to alter cell function by changing the structure of cell membrane receptors.
Discuss the importance of the placenta in the development of a healthy fetus. In your answer, be sure to:
• identify two factors that could influence the nutrients that can pass from the mother to the fetus [1]
• identify the group of hormones that alter cell membrane receptors and explain how this alteration can affect cell function [1]
• state the role of the uterus in the development of the fetus and the placenta [1]*
All organisms need to reproduce for the continuation of their species. Discuss the process of reproduction in humans. In your answer, be sure to:
• identify one hormone present in a female that is involved in regulating the reproductive cycle [1]
• state one way the nucleus of a sex cell is different from the nucleus of a body cell [1]
• state how the normal chromosome number for humans is maintained from one generation to the next [1]
• identify one action by the mother that can influence the development of the embryo and state a result of that influence [1]*
Base your answers to questions 18 on the information and diagram below and on your knowledge of biology.
Endometriosis is a condition that occurs in some women, causing multiple cells or layers of cells to grow outside of the uterus. In some cases, these growths can actually cover the entire ovary or cause the tube leading from the ovary to the uterus to be blocked. The diagram below represents the female reproductive system. Two structures, A and B, are labeled.
Select either surgical procedure or hormone therapy and explain why it can be an effective treatment for endometriosis. [1]
Effective treatment:*
Base your answers to questions 19 on the information below and on your knowledge of biology.
The testes of a human male produce gametes. The process that produces these gametes differs from the process that produces new skin cells in the same individual.
Identify the type of cell division involved in each process. [1]
Skin cells:
Gametes:*
Base your answers to questions 20 on the information below and on your knowledge of biology.
Placental mammals – as opposed to the kind that lay eggs, such as the platypus, or carry young in pouches, such as the kangaroo – are an extraordinarily diverse group of animals with more than 5000 species today. They [placental mammals] include examples that fly, swim, and run, and range in weight from a couple of grams to hundreds of tons. …
Source: “Earliest Placental Mammal Ancestor Pinpointed,” BBC News, February 7, 2013.
Describe one advantage for an offspring to develop internally as opposed to developing externally. [1]*
