Correct Answer: A. prolactin

Correct Answer: A. 1/2

Correct Answer: C) muscles or glands which work in response to the stimulus received from the motor nerves

Explanation

This Biology question is testing your knowledge of effectors. Effectors are either muscles or glands that work in response to the stimulus received from the motor nerves. The correct answer to this question is option C. Muscles and glands are both types of effectors that work in response to the stimulus received from the motor nerves. Muscles are responsible for movement in the body, while glands produce and secrete hormones and other substances. It's important to understand the relationship between effectors and motor nerves. Motor nerves are responsible for carrying signals from the brain and spinal cord to the effectors, telling them to either contract or secrete a substance. This is how the body is able to carry out various actions and functions. Remember, effectors are not the same as efferent neurons, which are responsible for carrying signals from the brain and spinal cord to the muscles and glands. Therefore, option D is not the correct answer to this question. In summary, effectors are either muscles or glands that work in response to the stimulus received from the motor nerves. They are responsible for carrying out various functions in the body, such as movement and secretion of hormones.

Correct Answer: C) sperm cell

Explanation

Human somatic cells are cells that make up the body of an individual, excluding the reproductive cells (sperm and egg cells). These cells contain 23 pairs of chromosomes, with one chromosome in each pair inherited from each parent. One of these pairs is the sex chromosomes, which determines the sex of the individual. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY). The question is asking where the chromosome that is not found in somatic cells is located. The correct answer is option C: sperm cell. This is because the sperm cell provides the other half of the genetic material needed to form a zygote during fertilization. The sperm cell contains either an X or a Y chromosome, which determines the sex of the offspring. It is important to note that the chromosome that is not found in somatic cells is the one that determines the sex of the individual, and this is because the somatic cells already contain the other sex chromosome. For example, in females, the somatic cells contain two X chromosomes, so the missing chromosome is the Y chromosome. To learn more about this, please read the relevant sections of the recommended textbooks.

Correct Answer: A. the workers are sterile

Correct Answer: D. they gnaw the bark and destroy

Correct Answer: C. tendons

Correct Answer: B) Sodium chloride

Explanation

Urine is a liquid waste product that is excreted by the kidneys. It is composed of water and various dissolved substances that the body needs to get rid of. This question is asking us to identify the substance that is not found in urine. The options given are: water, sodium chloride, nitrogenous compounds, calcium chloride, and nitrogenous salts. Water is a major component of urine and is necessary for the body to eliminate waste products. Nitrogenous compounds such as urea, uric acid, and creatinine are also found in urine. These compounds are produced by the breakdown of proteins in the body. Nitrogenous salts, such as ammonium chloride, are also found in urine. Sodium chloride, on the other hand, is not normally found in urine in significant amounts. This is because the kidneys are able to regulate the amount of sodium in the body and eliminate excess sodium through urine. Calcium chloride, while not a common component of urine, can sometimes be found in trace amounts. Therefore, the correct answer to this question is option B: Sodium chloride. It is important to note that this substance can be found in other bodily fluids, such as sweat and tears, but is not a major component of urine. Overall, understanding the composition of urine and the function of the kidneys is important in understanding this question. To learn more about this, please read the relevant sections of the recommended textbooks.

Correct Answer: B. All of these

Explanation

There are generally considered to be three major differences between DNA and RNA. 1) DNA has a main sugar of deoxyribose and RNA has a main sugar of ribose, 2) RNA uses uracil instead of thymine, and 3) RNA is almost exclusively a single-stranded nucleic acid. Further, DNA is generally the template that an organism uses to create RNA (except in specific organisms which use reverse transcriptase and use RNA to create DNA).

Correct Answer: D. Hydrogen

Explanation

The correct answer is hydrogen bonding, and each nucleotide attracts its pairing mate because they have corresponding number of hydrogen bonds. Adenine is attracted to thymine to create two hydrogen bonds, and cytosine is attracted to guanine to form three hydrogen bonds. While phosphodiester bonds are very important in creating the strand of DNA, they are not the bond that keeps the two strands in the double helix structure.