Which of the following is used to determine a person's DNA sequence?
A. Enzymes
B. Blood types
C. Hormones
D. Genes
Genes are used in the process of DNA sequencing to determine the order of nucleotides in a DNA molecule.
Choice B.
Blood types is not the correct answer because blood types are determined by the presence or absence of specific antigens on the surface of red blood cells and are not directly related to DNA sequencing.
Choice C.
Hormones is not the correct answer because hormones are chemical messengers produced by glands in the body and are not directly involved in DNA sequencing.
Choice D.
Genes is the correct answer because genes are used in the process of DNA sequencing to determine the order of nucleotides in a DNA molecule.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: Stimulus: 1of 1. A group of students performed an experiment to test terminal velocity, which is the greatest speed obtained by a falling object. The students dropped different numbers of coffee filters and measured the resulting terminal velocity. Which of the following conclusions is supported by the data in the following data table? #OF FILTERS MASS (g) TERMINAL VELOCITY (m/s) 1 1.01 1.74 2 1.99 2.48 3 3.02 3.04 4 4.0 3.50 5 5.01 3.80
A. Terminal velocity is when the force of gravity is equal to air resistance.
B. Heavier objects take more time to reach terminal velocity.
C. Heavier objects fall faster than lighter objects.
D. The greater the number of filters, the smaller the terminal velocity.
Answer Explanation
Heavier objects fall faster than lighter objects.
The data in the table shows that as the number of filters (and therefore the mass) increases, the terminal velocity also increases.
This means that the heavier objects (with more filters) are falling faster than the lighter objects (with fewer filters).
Choice A is not supported by the data in the table as much as it is true.
Terminal velocity is indeed when the force of gravity is equal to air resistance, but this definition does not provide any information about the relationship between mass and terminal velocity.
Choice B is also not supported by the data in the table.
The data does not provide any information about the time it takes for an object to reach terminal velocity.
Choice D is not supported by the data in the table.
The data shows that as the number of filters increases, the terminal velocity also increases.
This means that the greater the number of filters, the greater (not smaller) the terminal velocity.
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Q #2: Which of the following represents the complementary strand of a DNA sequence 3' TCGATCGCA 5'?
A. 3' AGCTAGCGT 5'
B. 5’ AGCTAGCGT 3’
C. 5' UCGAUCGCA 3'
D. 3' TCGUTCGCU 3'
Answer Explanation
In DNA, the nitrogenous bases adenine (A) and thymine (T) pair together, while cytosine (C) and guanine (G) pair together.
Therefore, the complementary strand of the given DNA sequence 3' TCGATCGCA 5' would have the complementary nitrogenous bases as:
5’ AGCTAGCGT 3’
NOTE: The 5’ to 3’ direction of the complementary strand is opposite to that of the given strand.
Choice A.
3’ AGCTAGCGT 5’ is not correct because it is not complementary to the given strand.
Choice C.
5’ UCGAUCGCA 3’ is not correct because it contains uracil (U), which is a nitrogenous base found in RNA, not DNA.
Choice D.
3’ TCGUTCGCU 3’ is not correct because it also contains uracil (U), which is a nitrogenous base found in RNA, not DNA.
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Q #3: Why is it important for new scientific findings to be published?
A. Scientists will get paid if their findings are published.
B. Publishing findings will help scientists become more biased.
C. Other scientists can validate or disprove the findings
D. This prevents other scientists from performing similar tests
Answer Explanation
Other scientists can validate or disprove the findings.
It is important for new scientific findings to be published so that other scientists can review the research and either validate or disprove the findings.
This process of peer-review helps to ensure the accuracy and reliability of scientific research.
Choice A.
Scientists will get paid if their findings are published is not correct because while some scientists may receive funding or grants for their research, the primary goal of publishing scientific findings is not for financial gain.
Choice B.
Publishing findings will help scientists become more biased is not correct because the goal of publishing scientific findings is to share information and promote transparency, not to promote bias.
Choice D.
This prevents other scientists from performing similar tests is not correct because publishing scientific findings allows other scientists to build upon the research and perform further tests to validate or disprove the findings.
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Q #4: In a plant in which fuzzy leaves (F) are dominant over smooth leaves (f), which of the following crosses will produce only offspring with smooth leaves?
A. FF x FF
B. Ff x Ff
C. ff x ff
D. Ff x ff
Answer Explanation
ff.
In this cross, both parents are homozygous recessive for the smooth leaf trait
(ff).
This means that all of their offspring will inherit two copies of the recessive allele (f) and will therefore have smooth leaves.
Choice A.
FF x FF is not correct because both parents are homozygous dominant for the fuzzy leaf trait (FF) and all of their offspring will inherit two copies of the dominant allele (F) and will therefore have fuzzy leaves.
Choice B.
Ff x Ff is not correct because both parents are heterozygous for the leaf trait (Ff) and their offspring can inherit either one dominant allele (F) or one recessive allele (f) from each parent, resulting in a 3:1 ratio of fuzzy to smooth leaves. Choice D.
Ff x ff is not correct because one parent is heterozygous for the leaf trait (Ff) while the other is homozygous recessive (ff), resulting in a 1:1 ratio of fuzzy to smooth leaves in their offspring.
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Q #5: Which of the following structures in the female reproductive system secretes hormones to maintain the uterine lining during pregnancy?
A. Umbilical cord
B. Corpus luteum
C. Oviduct
D. Oocyte
Answer Explanation
The corpus luteum is a structure that develops in the ovary after an egg has been released.
It secretes the hormone progesterone, which prepares the uterus for a fertilized egg to implant and helps maintain the uterine lining during pregnancy1.
Choice A.
Umbilical cord is not correct because it is a structure that connects the developing fetus to the placenta and provides nutrients and oxygen to the fetus, but does not secrete hormones.
Choice C.
Oviduct is not correct because it is a tube that transports eggs from the ovary to the uterus, but does not secrete hormones.
Choice D.
Oocyte is not correct because it is an immature egg cell, but does not secrete hormones.
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Q #6: Which of the following glands synthesizes antidiuretic hormone?
A. Pineal gland
B. Thymus
C. Hypothalamus
D. Pancreas
Answer Explanation
The hypothalamus is a region of the brain that synthesizes antidiuretic hormone (ADH), also known as vasopressin.
ADH is then transported to the posterior pituitary gland via neurohypophysial capillaries, where it is stored until it is ready to be secreted into the circulation.
Choice A.
Pineal gland is not correct because it is a small endocrine gland located in the brain that secretes the hormone melatonin, which regulates sleep-wake cycles, but it does not synthesize ADH.
Choice B.
Thymus is not correct because it is a gland located in the chest that produces hormones involved in immune system development, but it does not synthesize ADH.
Choice D.
Pancreas is not correct because it is a gland located behind the stomach that secretes hormones such as insulin and glucagon, which regulate blood sugar levels, but it does not synthesize ADH.
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Q #7: Which of the following indicates the function of sodium bicarbonate secreted by the pancreas?
A. Sodium bicarbonate is a protease that digests carbohydrates.
B. Sodium bicarbonate stimulates the pyloric sphincter.
C. Sodium bicarbonate inhibits peristalsis.
D. Sodium bicarbonate neutralizes the acidity of chyme.
Answer Explanation
Sodium bicarbonate neutralizes the acidity of chyme.
The pancreas secretes large amounts of sodium bicarbonate, which protects the duodenum by neutralizing the acid that comes from the stomach.
This compound helps neutralize stomach acid generated during the digestive process.
Choice A is incorrect because sodium bicarbonate is not a protease that digests carbohydrates.
Proteases are enzymes that break down proteins, while sodium bicarbonate is a chemical compound that helps neutralize stomach acid.
Choice B is incorrect because sodium bicarbonate does not stimulate the pyloric sphincter.
The pyloric sphincter is a ring of smooth muscle that separates the stomach from the duodenum and regulates the passage of partially digested food (chyme) into the small intestine.
Choice C is incorrect because sodium bicarbonate does not inhibit peristalsis.
Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract.
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Q #8: Which of the following allows the AIDS virus, which contains RNA, to insert viral DNA into the DNA of a host cell after the AIDS virus enters the cell?
A. The phospholipids found on the envelope of the virus.
B. Reverse transcriptase, an enzyme encoded by the virus.
C. Receptor proteins located on the surface of the virus.
D. The protein that makes up the capsid of the virus.
Answer Explanation
Reverse transcriptase, an enzyme encoded by the virus.
Reverse transcriptase is a virus-specific enzyme that transcribes an RNA template to DNA1.
This allows the AIDS virus, which contains RNA, to insert viral DNA into the DNA of a host cell after the AIDS virus enters the cell.
Choice A, The phospholipids found on the envelope of the virus, is not the correct answer because phospholipids are a major component of cell membranes and do not play a direct role in inserting viral DNA into the DNA of a host cell.
Choice C, Receptor proteins located on the surface of the virus, is not the correct answer because receptor proteins located on the surface of the virus play a role in attachment and fusion of HIV virons to host cells, but do not play a direct role in inserting viral DNA into the DNA of a host cell.
Choice D, The protein that makes up the capsid of the virus, is not the correct answer because capsid is the outer protein shell of a virus and does not play a direct role in inserting viral DNA into the DNA of a host cell.
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Q #9: Which of the following substances protects the skin from ultraviolet radiation?
A. Melanin
B. Perspiration
C. Sebum
D. Keratin
Answer Explanation
Melanin.
Melanin is a pigment produced by cells called melanocytes in the skin.
It protects the skin from ultraviolet (UV) radiation by absorbing and dissipating over 99.9% of absorbed UV radiation.
This helps to prevent DNA damage and other adverse effects of UV radiation on the skin.
Choice B.
Perspiration is not correct because it is a fluid produced by sweat glands in the skin that helps to regulate body temperature, but it does not protect the skin from UV radiation.
Choice C.
Sebum is not correct because it is an oily substance produced by sebaceous glands in the skin that helps to lubricate and protect the skin, but it does not protect the skin from UV radiation.
Choice D.
Keratin is not correct because it is a fibrous protein that provides strength and durability to the skin, hair and nails, but it does not protect the skin from UV radiation.
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Q #10: Nitrogen gas is an extremely stable molecule because of which of the following?
A. Ionic bonds
B. Hydrogen bonds
C. Resonance bonds
D. Triple covalent bonds
Answer Explanation
Triple covalent bonds.
Nitrogen gas (N2) is an extremely stable molecule because it consists of two nitrogen atoms bonded together by a triple covalent bond.
A covalent bond is a type of chemical bond where atoms share electrons to form a molecule.
In a triple covalent bond, three pairs of electrons are shared between the two atoms, resulting in a very strong bond that makes the molecule extremely stable.
Choice A.
Ionic bonds is not correct because ionic bonds involve the transfer of electrons from one atom to another to form ions, which are then attracted to each other due to their opposite charges.
Nitrogen gas does not contain ions and is not held together by ionic bonds.
Choice B.
Hydrogen bonds is not correct because hydrogen bonds are weak electrostatic attractions between molecules that contain hydrogen atoms bonded to highly electronegative atoms such as oxygen or nitrogen.
Nitrogen gas does not contain hydrogen atoms and is not held together by hydrogen bonds.
Choice C.
Resonance bonds is not correct because resonance refers to the delocalization of electrons in a molecule where multiple Lewis structures can be drawn to represent the molecule.
Nitrogen gas has a single Lewis structure and does not exhibit resonance.
