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To accurately measure the density of a series of small irregular solids made of plastic, wood, fibreglass, and glass, a student will need which of the following laboratory tools?

A. Graduated cylinder, water, weighing balance

B. Graduated cylinder, spectrophotometer, water

C. Graduated beaker, metric ruler, water

D. Weighing balance, Bunsen burner, metric ruler

Answer Explanation:

To accurately measure the density of a series of small irregular solids made of plastic, wood, fiberglass, and glass, a student will need a graduated cylinder, water, and a weighing balance. The student can use the water displacement method to determine the volume of each solid by measuring the volume of water displaced when the solid is submerged in a graduated cylinder filled with water. The mass of each solid can be measured using a weighing balance. The density can then be calculated by dividing the mass by the volume.

The other options are not correct because they do not provide the necessary tools to accurately measure the density of the solids. A spectrophotometer is used to measure light absorption and is not necessary for measuring density. A graduated beaker is less accurate than a graduated cylinder for measuring volume. A Bunsen burner is used for heating and is not necessary for measuring density.

Therefore, the Correct Answer is A.

More Questions on TEAS 7 Science

  • Q #1: Which of the following is the process in which an ovarian follicle matures and releases a reproductive egg?

    A. Oogenesis

    B. Menstruation

    C. Ovulation

    D. Fertilization

    Answer Explanation

    Ovulation is the process in which an ovarian follicle matures and releases a reproductive egg. During ovulation, the egg is released from the ovary and travels down the fallopian tube where it may be fertilized by sperm.

    The other options are not processes in which an ovarian follicle matures and releases a reproductive egg. Oogenesis is the process of egg cell formation, menstruation is the shedding of the uterine lining, and fertilization is the fusion of an egg and sperm to form a zygote.

  • Q #2: Which of the following structures is present in both prokaryotic and eukaryotic cells?

    A. Endoplasmic reticulum

    B. Cell membrane

    C. Chloroplast

    D. Golgi apparatus

    Answer Explanation

    The structure that is present in both prokaryotic and eukaryotic cells is the cell membrane ². The cell membrane is a thin layer that surrounds the cell and separates its internal environment from the external environment ². It is composed of a lipid bilayer and proteins and regulates the movement of substances into and out of the cell ².

    The other options are not correct because they are not present in both prokaryotic and eukaryotic cells. The endoplasmic reticulum, chloroplast, and Golgi apparatus are organelles that are only found in eukaryotic cells ².

  • Q #3: Which of the following properties does soap, an emulsifier, have that make it useful for washing dirt off one’s hands with water?

    A. Soap’s dual polar and nonpolar nature helps bond oil and water

    B. Soap’s acidity causes grime to precipitate into the water

    C. Soap’s enzymatic action helps to dissolve grime into small particles

    D. Soap’s rough texture physically scours grime off surfaces

    Answer Explanation

    The correct answer is a. Soap’s dual polar and nonpolar nature helps bond oil and water. Soap is an emulsifier, which means that it has both polar and nonpolar regions. The polar regions of soap molecules are atracted to water, while the nonpolar regions are atracted to oil and grease. This allows soap to bond with both water and oil, helping to remove dirt and grime from surfaces.

    B. Soap’s acidity does not cause grime to precipitate into the water.

    C. Soap does not have enzymatic action that helps to dissolve grime into small particles.

    D. Soap’s texture does not physically scour grime off surfaces.

  • Q #4: In which of the following regions of the body are the tibia and fibula?

    A. Coxal

    B. Antecubital

    C. Tarsal

    D. Crural

    Answer Explanation

    The tibia and fibula are located in the crural region of the body, which is the lower leg between the knee and ankle. The coxal region refers to the hip area, the antecubital region is the front of the elbow, and the tarsal region is the ankle and foot.

  • Q #5: Which of the following layers of skin lack blood vessels?

    A. Papillary

    B. Epidermis

    C. Reticular

    D. Hypodermis

    Answer Explanation

    The layer of skin that lacks blood vessels is the epidermis. The epidermis is the thin outer layer of the skin and does not have any blood vessels within it. It is composed of keratinized, stratified squamous epithelium and is made of four or five layers of epithelial cells, depending on its location in the body.

    The other options are not correct because they do contain blood vessels. The papillary layer is part of the dermis, which contains blood vessels. The reticular layer is also part of the dermis and contains blood vessels . The hypodermis is a layer below the dermis and also contains blood vessels.

  • Q #6: An individual suffers severe blunt trauma to the thoracic cavity. Which of the following organs are at greatest risk from this injury?

    A. Heart and lungs

    B. Brain and spinal cord

    C. Liver and stomach

    D. Large and small intestines

    Answer Explanation

    The correct answer is a. Heart and lungs. The thoracic cavity contains the heart and lungs, which are at greatest risk from severe blunt trauma to this area.

    a.The brain and spinal cord are not located in the thoracic cavity and are therefore not at greatest risk from blunt trauma to this area.

    c.The liver and stomach are located in the abdominal cavity, which is below the thoracic cavity. While these organs may be affected by severe blunt trauma to the thoracic cavity, they are not at greatest risk.

    d.The large and small intestines are also located in the abdominal cavity and are not at greatest risk from blunt trauma to the thoracic cavity.

     

  • Q #7: Which of the following actions allows for repolarization of a neuron?

    A. The inhibition of sodium and potassium pumps, stopping all ion movement into the neuron

    B. The opening of sodium channels, allowing sodium to enter the neuron

    C. The closing of both sodium and potassium channels to restrict movement of ions into and out of the neuron

    D. The opening of potassium channels allowing potassium to leave the neuron

    Answer Explanation

    D. The opening of potassium channels allowing potassium to leave the neuron

    The correct answer is d. The opening of potassium channels allowing potassium to leave the neuron. Repolarization of a neuron occurs after an action potential, when the neuron's membrane potential returns to its resting state. This is achieved by the opening of potassium channels, which allows potassium ions to flow out of the neuron. This movement of positively charged ions out of the neuron helps to restore the negative membrane potential.

    A. The inhibition of sodium and potassium pumps would not allow for repolarization because these pumps are necessary for maintaining the resting membrane potential.

    B. The opening of sodium channels would cause depolarization, not repolarization.

    C. The closing of both sodium and potassium channels would restrict ion movement, but it would not allow for repolarization.

  • Q #8: Experiments cannot validate hypotheses, only falsify them. The statement above can be restated in which of the following ways?  

    A. a. Until disproved, an explanation for an observation is valid.

    B. b. Certain concepts cannot be subjected to direct experimentation.

    C. c. A hypothesis that has not been falsified remains provisional.

    D. d. Proving a hypothesis exempts it from further testing

    Answer Explanation

     

    The statement "Experiments cannot validate hypotheses, only falsify them" can be restated as "A hypothesis that has not been falsified remains provisional." This means that a hypothesis is considered valid until it is disproved by experimental evidence. However, even if a hypothesis has not been falsified, it is still considered provisional and subject to further testing and scrutiny.

    a."Until disproved, an explanation for an observation is valid" is similar to the correct answer but does not capture the provisional nature of a hypothesis.

    b."Certain concepts cannot be subjected to direct experimentation" is not a restatement of the original statement.

           d. "Proving a hypothesis exempts it from further testing" is incorrect because no hypothesis can be definitively proven and all hypotheses are subject to further testing and         scrutiny.

  • Q #9: Which of the following is a component of the integumentary system that secretes pheromones?

    A. Fossa ovalis

    B. Seminiferous tubule

    C. Dermal papilla

    D. Apocrine gland

    Answer Explanation

    The apocrine gland is a component of the integumentary system that secretes pheromones. Pheromones are chemical signals that are released by an individual and can affect the behavior or physiology of other individuals of the same species.

    The other options are not components of the integumentary system that secrete pheromones. The fossa ovalis is a depression in the interatrial septum of the heart, the seminiferous tubule is a structure in the testes where sperm are produced, and the dermal papilla is a structure at the base of a hair follicle that provides nutrients to the hair.

  • Q #10: Which of the following functions does the myelin sheath perform for a nerve cell?

    A. Insulation

    B. Regeneration

    C. Sensory perception

    D. Nutrition

    Answer Explanation

    The myelin sheath is a protective membrane that wraps around parts of certain nerve cells.

    Its fatty-protein coating provides protective insulation for your nerve cell like the plastic insulation covering that encases the wires of an electrical cord ².

    This allows the electrical impulses to travel quickly and efficiently between one nerve cell and the next. The other options are incorrect because they do not describe the functions of the myelin sheath.

    Regeneration, sensory perception, and nutrition are not functions performed by the myelin sheath for a nerve cell.