The measurement indicated by the line across the center of the cell is best referred to as which of the following?
A. Area.
B. Diameter.
C. Volume.
D. Radius.
Diameter.
The diameter is the measurement of a straight line passing through the center of a circle and connecting two points on its circumference.
In this case, the line across the center of the cell represents the diameter of the cell.
Choice A, Area, is not the correct answer because area refers to the amount of space inside a two-dimensional shape.
Choice C, Volume, is not the correct answer because volume refers to the amount of space occupied by a three-dimensional object.
Choice D, Radius, is not the correct answer because radius refers to the distance from the center of a circle to its circumference and is half the length of the diameter.
Therefore, the Correct Answer is B.
More Questions on TEAS 7 Science
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Q #1: To separate genomic DNA fragments by size, which of these laboratory methods is most useful?
A. Titration
B. Electrophoresis
C. Filtration
D. Spectrophotometry
Answer Explanation
Electrophoresis is the most useful laboratory method for separating genomic DNA fragments by size.
Electrophoresis is a technique that uses an electric field to separate charged molecules, such as DNA fragments, based on their size and charge.
Choice A is not correct because titration is a laboratory method used to determine the concentration of a solution.
Choice C is not correct because filtration is a laboratory method used to separate solids from liquids.
Choice D is not correct because spectrophotometry is a laboratory method used to measure the absorbance of light by a solution.
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Q #2: Which of the following are the two major parts of the nervous system?
A. Autonomic nervous system and somatic nervous system.
B. Peripheral nervous system and somatic nervous system
C. Peripheral nervous system and central nervous system.
D. Autonomic nervous system and central nervous system.
Answer Explanation
The two major parts of the nervous system are the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).
The CNS is made up of the brain and spinal cord and acts as the integration and command center of the body.
The PNS represents the conduit between the CNS and the body and is further subdivided into the somatic nervous system (SNS) and the autonomic nervous system (ANS).
Choice A is incorrect because it only mentions two subdivisions of the PNS, which are the autonomic nervous system (ANS) and somatic nervous system (SNS).
Choice B is incorrect because it only mentions one major part of the nervous system, which is the PNS, and one subdivision of it, which is the SNS.
Choice D is incorrect because it only mentions one major part of the nervous system, which is the CNS, and one subdivision of the PNS, which is the ANS.
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Q #3: In a phase diagram, which of the following is the term used for a substance held at a temperature and pressure where the solid, liquid, and gaseous states of a substance exist simultaneously?
A. Triple point
B. Critical temperature
C. Critical point
D. Absolute zero
Answer Explanation
Triple point.
In a phase diagram, the term used for a substance held at a temperature and pressure where the solid, liquid, and gaseous states of a substance exist simultaneously is the triple point.
The triple point is a unique point on a phase diagram where the three states of matter (solid, liquid, and gas) can coexist in equilibrium.
At the triple point, the temperature and pressure of the substance are fixed.
Option B, critical temperature, is the temperature at which a gas cannot be liquefied, regardless of the pressure applied.
It is a characteristic property of a substance and is typically higher than the boiling point of the liquid at standard pressure.
Option C, critical point, is the point on a phase diagram where the liquid and gas phases of a substance become indistinguishable.
At the critical point, the distinction between the liquid and gas phases disappears, and the substance becomes a supercritical fluid.
Option D, absolute zero, is the theoretical temperature at which all matter has zero thermal energy.
At absolute zero, all substances are in their solid state, but it is not relevant to a phase diagram, as it is a temperature where no transitions between states occur.
In summary, the term used for a substance held at a temperature and pressure where the solid, liquid, and gaseous states of a substance exist simultaneously in a phase diagram is the triple point, whereas the other options provided are not relevant or are characteristic properties of substances in different contexts.
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Q #4: Parasitic worm infestation is hypothesized to be damaging to the host. However, scientists have recently discovered that worm infestation can relieve the effects of certain autoimmune disorders. In which of the following ways should the hypothesis be modified, given the new findings?
A. Worm infestation prevents the body from immune malfunction
B. Worm infestation reduces the severity of certain autoimmune disorders
C. Worm infestations exacerbate the body's immune reactions
D. Lack of worm infestations is the cause of some autoimmune disorders
Answer Explanation
The hypothesis should be modified to include the new findings that worm infestation can relieve the effects of certain autoimmune disorders.
A possible modification could be: “Parasitic worm infestation can have both damaging and beneficial effects on the host.
While it can cause harm, it has also been found to reduce the severity of certain autoimmune disorders.”
Choice A.
Worm infestation prevents the body from immune malfunction is not correct because it overstates the findings and implies that worm infestation completely prevents immune malfunction, which is not supported by the evidence.
Choice C.
Worm infestations exacerbate the body’s immune reactions is not correct because it contradicts the new findings that worm infestation can relieve the effects of certain autoimmune disorders.
Choice D.
Lack of worm infestations is the cause of some autoimmune disorders is not correct because it overstates the findings and implies a causal relationship between lack of worm infestations and autoimmune disorders, which is not supported by the evidence.
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Q #5: Which of the following is used to determine a person's DNA sequence?
A. Enzymes
B. Blood types
C. Hormones
D. Genes
Answer Explanation
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.
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Q #6: Which of the following microorganisms lack their own metabolic pathways and can only reproduce inside of a host cell?
A. Bacteria
B. Protozoa
C. Helminths
D. Viruses
Answer Explanation
Viruses.
Viruses lack essential machinery needed to reproduce by themselves.
In fact, viruses can only reproduce after infecting a living cell - a process called viral replication.
Once inside a living cell, viruses re-program the cell’s machinery to produce viral proteins and genetic material to make new copies of themselves.
Choice A, Bacteria, is not the correct answer because bacteria have their own metabolic pathways and can reproduce outside of a host cell.
Choice B, Protozoa, is also not the correct answer because protozoa are singlecelled eukaryotes that have their own metabolic pathways and can reproduce outside of a host cell.
Choice C, Helminths, is not the correct answer because helminths are multicellular parasitic worms that have their own metabolic pathways and can reproduce outside of a host cell.
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Q #7: Which of the following vessels carries oxygenated blood?
A. Superior vena cava
B. Inferior vena cava.
C. Pulmonary artery
D. Pulmonary vein
Answer Explanation
The pulmonary veins are the vessels that carry oxygenated blood from the lungs to the left atrium of the heart.
Choice A is not correct because the superior vena cava carries deoxygenated blood from the upper body to the right atrium of the heart.
Choice B is not correct because the inferior vena cava carries deoxygenated blood from the lower body to the right atrium of the heart.
Choice C is not correct because the pulmonary artery carries deoxygenated blood from the right ventricle of the heart to the lungs.
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Q #8: Which of the following is the process in which an ovarian follicle matures and releases a reproductive egg?
A. Menstruation
B. Fertilization
C. Ovulation
D. Oogenesis
Answer Explanation
Ovulation is the process in which an ovarian follicle matures and releases a reproductive egg.
During ovulation, a mature egg is released from the female ovary, enabling it to be fertilized by male sperm cells 1.
Choice A is incorrect because menstruation is the process of shedding the uterine lining, which occurs when an egg is not fertilized.
Choice B is incorrect because fertilization is the process of a sperm cell joining with an egg cell to form a zygote.
Choice D is incorrect because oogenesis is the process of forming female gametes (eggs) in the ovaries.
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Q #9: Which of the following is the atomic number of an atom that has 12 protons and 12 neutrons?
A. 24
B. 12
C. 1
D. 144
Answer Explanation
The atomic number of an atom is equal to the number of protons in its nucleus.
In this case, the atom has 12 protons, so its atomic number is 12.
Choice A, 24, is not the correct answer because it represents the sum of the number of protons and neutrons in the atom’s nucleus, which is known as the mass number.
Choice C, 1, is not the correct answer because it does not represent the number of protons in the atom’s nucleus.
Choice D, 144, is not the correct answer because it represents the square of the mass number and does not represent any property of the atom.
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Q #10: In the following data table of an experiment carried out at 4°C (39.2 F) over 4 hours Solution in bag Solution outside bag Bag mass change (g): water Water -0.2 20% sucrose Water +2.4 , 40% sucrose Water +4.3 , 60% sucrose water +5.8 Which of the following options represents the dependent variable?
A. Duration
B. Temperature
C. Bag mass change
D. Solution used outside
Answer Explanation
Bag mass change is the dependent variable in this experiment.
In an experiment, the dependent variable is the variable that is being measured and is expected to change in response to changes in the independent variable(s).
In this case, the bag mass change is being measured and is expected to change in response to changes in the independent variable (sucrose concentration).
Choice A is incorrect because duration is not a variable in this experiment.
Choice B is incorrect because temperature is not a variable in this experiment.
Choice D is incorrect because sucrose concentration is an independent variable, not a dependent variable.
An independent variable is a variable that is manipulated by the experimenter to see how it affects the dependent
