Which of the following is a function of the respiratory system?
A. Transport of nutrients to the body
B. Pumping of blood to the lungs
C. Exchange of gases between the body and the environment
D. Digeson of food in the stomach
One of the main funcons of the respiratory system is to facilitate the exchange of gases between the body and the environment. During inhalaon, air enters the lungs and oxygen is absorbed into the bloodstream. During exhalaon, carbon dioxide is removed from the body and expelled into the environment.
Therefore, the Correct Answer is C.
More Questions on TEAS 7 Science
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Q #1: What is the difference between a solid and a liquid?
A. Solids have a definite shape and volume while liquids have a definite volume but no fixed shape.
B. Solids have no definite shape or volume while liquids have a definite volume and take the shape of their container.
C. Solids and liquids have the same physical properties.
D. Solids have a definite volume but take the shape of their container while liquids have a definite shape and volume.
Answer Explanation
The main difference between a solid and a liquid is their physical state and the way their particles are arranged. In a solid, the particles are tightly packed together and have a fixed position, which gives the solid a definite shape and volume. Solids are also characterized by their high density, low compressibility, and high thermal conductivity.
In contrast, the particles in a liquid are more loosely packed and can move around each other, which allows the liquid to take the shape of its container. Liquids have a definite volume but no fixed shape, which means they can be poured or spilled. Liquids also have a lower density than solids, are more compressible than solids, and have lower thermal conductivity than solids.
Option b) is incorrect because it describes the properties of a gas, not a liquid. Option c) is incorrect because solids and liquids have different physical properties. Option d) is incorrect because it describes the properties of a gas, not a liquid or a solid.
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Q #2: What is the difference between innate and adaptive immunity?
A. Innate immunity is present at birth while adaptive immunity is acquired after exposure to pathogens.
B. Innate immunity is acquired after exposure to pathogens while adaptive immunity is present at birth.
C. Innate immunity is mediated by antibodies while adaptive immunity is mediated by T cells.
D. Innate immunity provides long-term protection while adaptive immunity provides only short-term protection.
Answer Explanation
Innate immunity and adaptive immunity are two arms of the immune system that work together to protect the body from pathogens. Innate immunity is the first line of defense and is present at birth. It includes physical and chemical barriers such as the skin, mucous membranes, and antimicrobial peptides, as well as cells such as macrophages and natural killer cells that can quickly recognize and atack pathogens. Innate immunity is nonspecific, meaning it responds to a wide variety of pathogens in a similar way.
Adaptive immunity, on the other hand, is acquired after exposure to pathogens. It involves the production of antibodies and activation of T cells, which are specific to particular pathogens. Adaptive immunity takes longer to develop than innate immunity, but it provides a more specific and targeted response to pathogens. Once the adaptive immune system has been activated against a particular pathogen, it can provide long-term protection against future infections with that pathogen.
Option b) is incorrect because innate immunity is nonspecific while adaptive immunity is specific. Option c) is incorrect because antibodies are a part of adaptive immunity while T cells can be a part of both innate and adaptive immunity. Option d) is incorrect because adaptive immunity can provide long-term protection, while innate immunity provides immediate but short-lived protection.
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Q #3: What is the name of the genetic disorder caused by the presence of an extra chromosome 21?
A. Turner syndrome
B. Klinefelter syndrome
C. Down syndrome
D. Huntington's disease
Answer Explanation
Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21. It is also known as trisomy 21, because affected individuals have three copies of chromosome 21 instead of the normal two.
The extra chromosome 21 in Down syndrome occurs due to a random error in cell division, which leads to the production of an abnormal gamete (egg or sperm) with an extra copy of the chromosome. When this gamete fuses with a normal gamete during fertilization, the resulting zygote has 47 chromosomes instead of the usual 46, and develops into a fetus with Down syndrome.
Down syndrome is characterized by a range of physical and intellectual symptoms, including developmental delays, intellectual disability, distinctive facial features, heart defects, and increased risk of certain medical conditions such as leukemia and Alzheimer's disease. However, the severity and expression of these symptoms can vary widely among affected individuals.
