Answer the following question given this paragraph: Connective Tissues Connective tissues are made up of a matrix consisting of living cells and a non-living substance, called the ground substance. The ground substance is made of an organic substance (usually a protein) and an inorganic substance (usually a mineral or water). The principal cell of connective tissues is the fibroblast. This cell makes the fibers found in nearly all of the connective tissues. Fibroblasts are motile, able to carry out mitosis, and can synthesize whichever connective tissue is needed. Macrophages, lymphocytes, and, occasionally, leukocytes can be found in some of the tissues. Some tissues have specialized cells that are not found in the others. The matrix in connective tissues gives the tissue its density. When a connective tissue has a high concentration of cells or fibers, it has proportionally a less dense matrix. The organic portion or protein fibers found in connective tissues are either collagen, elastic, or reticular fibers. Collagen fibers provide strength to the tissue, preventing it from being torn or separated from the surrounding tissues. Elastic fibers are made of the protein elastin; this fiber can stretch to one and one half of its length and return to its original size and shape. Elastic fibers provide flexibility to the tissues. Reticular fibers are the third type of protein fiber found in connective tissues. This fiber consists of thin strands of collagen that form a network of fibers to support the tissue and other organs to which it is connected. The various types of connective tissues, the types of cells and fibers they are made of, and sample locations of the tissues is summarized in Table 33.3. Q: What is the principal cell of connective tissues? Choices: - organism - Cancer - neural - fibroblast A:
fibroblast
(Question)
Answer the following question given this paragraph: Female Hormones The control of reproduction in females is more complex. The female reproductive cycle is divided into the ovarian cycle and the menstrual cycle. The ovarian cycle governs the preparation of endocrine tissues and release of eggs, while the menstrual cycle governs the preparation and maintenance of the uterine lining (Figure 18.17). These cycles are coordinated over a 2232 day cycle, with an average length of 28 days. As with the male, the GnRH from the hypothalamus causes the release of the hormones FSH and LH from the anterior pituitary. In addition, estrogen and progesterone are released from the developing follicles. As with testosterone in males, estrogen is responsible for the secondary sexual characteristics of females. These include breast development, flaring of the hips, and a shorter period for bone growth. The Ovarian Cycle and the Menstrual Cycle The ovarian and menstrual cycles are regulated by hormones of the hypothalamus, pituitary, and ovaries (Figure 18.17). The ebb and flow of the hormones causes the ovarian and menstrual cycles to advance. The ovarian and menstrual cycles occur concurrently. The first half of the ovarian cycle is the follicular phase. Slowly rising levels of FSH cause the growth of follicles on the surface of the ovary. This process prepares the egg for ovulation. As the follicles grow, they begin releasing estrogen. The first few days of this cycle coincide with menstruation or the sloughing off of the functional layer of the endometrium in the uterus. After about five days, estrogen levels rise and the menstrual cycle enters the proliferative phase. The endometrium begins to regrow, replacing the blood vessels and glands that deteriorated during the end of the last cycle. Q: What two cycles make up the female reproductive cycle? Choices: - ovarian and cesarean - cervical and menstrual - digestive and menstrual - ovarian and menstrual A:
(Answer)
ovarian and menstrual
Ques: Answer the following question given this paragraph: Q: What organs have tiny tubes leading to and from elastic air sacs that improve airflow and oxygen uptake? Choices: - ovaries - apendix - liver - lungs A:
Ans: lungs
(Q).
Answer the following question given this paragraph: Alkanes contain only carbon-carbon single bonds. Q: What type of bonds do alkanes only contain? Choices: - hydrogen bonds - carbon-hydrogen bonds - hydrogen-carbon bonds - carbon-carbon single bonds A:
(A).
carbon-carbon single bonds
Ques:Answer the following question given this paragraph: A low level of radiation occurs naturally in the environment. This is called background radiation. One source of background radiation is rocks, which may contain small amounts of radioactive elements such as uranium. Another source is cosmic rays. These are charged particles that arrive on Earth from outer space. Background radiation is generally considered to be safe for living things. You can learn more about background radiation with the animation at this URL: http://www. pbs. org/wgbh/nova/dirtybomb/sources. html. Q: A low level of radiation occurs naturally in the environment and is called what? Choices: - Gamma radiation - Beta radiation - Alpha radiation - background radiation A:

Ans:background radiation
Answer the following question given this paragraph: 500. mm is equivalent to 0.5 m. Q: How many centimeters are in a meter? Choices: - 50 - 200 - 1000 - 100 A:
100