Teas Practice Test B Science

Which of the following properties of water explains its characterization as the universal solvent?

Kinetic energy of liquid water molecules

High specific heat

Polarity of water molecules

High surface tension

C Polarity of water molecules

Polarity means water molecules can form shells around both positively and negatively charged particles. Therefore, water can solubilize ionic and covalent molecules with charge separation, making it a universal solvent.

A student observes that when the mercury rises and falls in a thermometer, the particles do not stick to the sides of the glass tube. However, when honey is poured from one glass container to another, the particles stick to the walls of the container. Which of the following explains the observation?

Mercury is more cohesive and less adhesive than honey.

Mercury is less cohesive and more adhesive than honey.

Mercury is less cohesive and less adhesive than honey.

Mercury is more cohesive and more adhesive than honey.

A Mercury is more cohesive and less adhesive than honey

Mercury atoms are more attracted to each other by cohesion than they are to glass by adhesion, while honey has high adhesion and sticks immediately to the glass surface. So, mercury rises and falls without any residue on the thermometer while honey sticks to the container.

Which of the following describes the concentration of hydrogen ions in water with a pH of 7?

107 M

7 M

0.7 M

10-7 M

D 10-7

The formula for pH is -log[H+]. Therefore, the concentration of hydrogen ions in water with a pH of 7 is 0.0000001 M (10-7 M).

Which of the following anatomical planes divides the body into superior and inferior portions?

Sagittal

Median

Frontal

Transverse

D Transverse

The transverse plane divides the body into upper (superior) and lower (inferior) portions.

Which of the following is 4/100 expressed as a percent?

0.04%

0.4%

4%

400%

C

A student wants to study how friction affects the distance traveled by a marble on a surface. A marble was pushed on four different surfaces with the same force and the time taken for it to travel 1 meter was noted. What experimental term is used to define the condition of pushing the marble with same force on all four surfaces?

Data collection

Dependent variable

Independent variable

Experimental constant

D Experimental Constant

A condition that is kept the same for each experimental group is called a constant.

Which of the following pathogens would be unaffected by treatment with an antibiotic that inhibits ribosome function?

Viruses

Bacteria

Protists

Fungi

A viruses

Viruses do not contain ribosomes. They use host ribosomes for protein synthesis. They are also not alive and cannot be treated by antibiotics.

When calculating population growth, which of the following equations is appropriate?

(Emigrants - immigrants) + (births - deaths)

(Immigrants - emigrants) + (births - deaths)

(Births + deaths) - (emigrants + immigrants)

(Births - deaths) - (immigrants + emigrants)

B (Immigrants - emigrants) + (Births - Deaths)

This calculation correctly adds the difference between people entering (immigration and births) and leaving the population (emigrants and deaths).

Which of the following hormones is released in response to a drop in blood pressure?

Melatonin

Somatostatin

Oxytocin

Aldosterone

D Aldosterone

Aldosterone retains salt in the kidneys and results in water retention, which increases blood volume and pressure.

Which of the following cells rid the body of dust and other particles that enter the lungs?

Alveoli

Macrophages

Sertoli cells

Erythrocytes

B Macrophages

Alveolar macrophages are abundant in the lungs and remove particles that escape entrapment by mucus.

"Dark matter" is a form of energy proposed to explain the repulsive forces between matter in the universe. It has never been observed directly. Which of the following is the best rationale for many scientists' contention that it exists?

It serves as a working hypothesis to explain real observations in the universe.

A basic scientific principle is to consider everything possible until proven otherwise.

Since light energy exists in the universe, dark energy must also exist.

Light energy from distant stars is very faint because it is absorbed by dark energy.

A It serves as a working hypothesis to explain real observation in the universe

Often scientists will make such a working hypothesis and assume an entity that fits the observed data. This strategy allows for experimental testing.

A chlorine atom has 17 electrons and 17 protons. It forms an ionic bond with sodium and gains a negative charge. Which of the following is true for the chloride ion?

It is an anion with 18 electrons and 17 protons.

It is an anion with 18 electrons and 18 protons.

It is a cation with 17 electrons and 18 protons.

It is a cation with 18 electrons and 18 protons.

A it is an anion with 18 electrons and 17 protons

When a chlorine atom gains an electron, its negative charge increases by 1 and it is now called an anion.

Which of the following cell types confers waterproofing on the outer layers of skin?

Melanocytes

Keratinocytes

Merkel cells

Langerhans cells

B Kertinocytes

Keratinocytes contain the protein keratin and are produced in the epidermis and migrate upward. The tight junctions between cells prevents water entry. They eventually form a layer of dead cells on the skin surface.

Which of the following statements accurately describes systemic circulation?

Supplies oxygen-poor blood from the right ventricle to the lungs

Receives oxygen-rich blood from the lungs to the right atrium

Supplies oxygen-rich blood from the left ventricle to the body

Receives oxygen-poor blood from the body to the left atrium

C supplies oxygen-rich blood from the left ventricle to the body

In systemic circulation, the left ventricle supplies oxygen-rich blood to the body, and the right atrium receives oxygen-poor blood from the body.

A student is assigned the task of measuring the weight of one tennis ball using a scale for which the zero adjustment on the balance is not working. The student is given three balls and the can in which they were packaged. Which of the following strategies will provide the best determination of the correct weight?

Weigh each ball separately and average the results.

Weigh the empty can, weigh the can with a ball in it, and compute the difference between the two.

Weigh the three balls together and divide by three.

Weigh each ball separately, adjusting the beam weights from below first, and then from above. Then, average the results.

B Weigh the empty can, weigh the can with the ball in it and compute the difference between the two

Finding the difference between the can with a ball in it and without a ball will provide the weight of the ball.

Which of the following is the value of the prefix milli- in the metric system?

10-6

1000

10-3

0.1

10-3

This value represents the prefix milli-, or 1/1000.

Which of the following statements is correct regarding the organisms in which photosynthesis and oxidative respiration occur?

Photosynthesis occurs only in plants, whereas oxidative respiration occurs in all life forms.

Photosynthesis occurs in many prokaryotes and some eukaryotes, whereas oxidative respiration occurs only in aerobic eukaryotes.

Photosynthesis occurs only in plants, whereas oxidative respiration occurs only in animals.

Photosynthesis occurs in many prokaryotes and eukaryotes, whereas oxidative respiration occurs only in aerobic prokaryotes and eukaryotes.

D photosynthesis occurs in many prokaryotes and eukaryotes, whereas oxidative respiration occurs only in aerobic prokaryotes and eukaryotes

Photosynthesis occurs in bacteria, certain protists, and plants, and oxidative respiration occurs in aerobes.

Which of the following is a type of specialized antigen-processing cell that activates T-cells of the immune system?

Plasma cells

Thrombocytes

Dendritic cells

Eosinophils

C dendrite cells

Dendritic cells process antigens and display them on surface receptors to helper T-cells of the immune system. Helper T-cells then activate cytotoxic T-cells and B-cells. Therefore, dendritic cells link the passive and active immune system.

Which of the following is the main function of bile juices?

Breaking down proteins

Emulsifying fats

Detoxifying poisons

Digesting carbohydrates

B Emulsifying fats

Bile juices contain surfactants that aid in fat emulsification and increase surface area for its digestion by lipases from the small intestine and pancreas.

Which of the following is the circular muscle that regulates the opening and closing of a body aperture?

Fossa

Fascia

Sphincter

Valve

C Sphincter

A sphincter is a circular muscle fascicle that opens and closes body apertures. There are several sphincters in the human body, including the anal sphincter and pyloric sphincter.

Acid reflux is a condition in which the gastric juices of the stomach flow backward into the esophagus. Which of the following causes acid reflux?

The cardiac sphincter does not close tightly.

Peristalsis occurs slowly in the esophagus.

Excess gastric juices are produced by the stomach.

The pH value for gastric juices is increased.

A The cardiac sphincter does not close tightly

Acid reflux occurs when gastric juices, which otherwise stay inside the stomach, flow backward into the esophagus because the cardiac sphincter does not close tightly.

In chickens, feather color can be white (WW), black (BB), or speckled (BW). A cross between a black-feathered chicken and a white-feathered chicken produces speckled-feathered chickens. Which of the following is the outcome of a cross between two F1 offspring?

1 BB: 1 BW: 1 WW

1 BB: 2 BW: 1 WW

2 BB: 1 BW: 1 WW

1 BB: 1 BW: 2 WW

B) 1 BB: 2 BW: 1 WW

B and W are codominant alleles. Therefore, the genotype of all F1 offspring is BW. An F1 cross between two BW offspring will produce 1 BB: 2 BW: 1 WW in the F2 generation.

Which of the following statements best explains why RNA inside a cell is almost never found as a single-stranded molecule?

Alleles for genes are found in pairs, so their RNAs also pair up.

RNA normally exists with its complementary strand in a double helix.

RNA and DNA form hybrid pairs for all transcribing parts of the chromosome.

Short stretches of complementary sequences can cause RNA to fold back on itself.

D Short stretches of complementary sequences can cause RNA to fold back on itself.

Even short segments of RNA that are complementary can pair with each other within a single strand.

An atom of lithium has 3 protons, 4 neutrons, and 3 electrons. What is this atom's mass number?

3

6

10

7

D 7

The mass number of an atom is the sum of the number of protons and neutrons in its nucleus.

In human blood types, A and B alleles are codominant and O is recessive. Which of the following combinations of the parents' genotypes has the highest probability of producing a child with blood type O?

Both parents are heterozygous and have blood type AB.

One parent is heterozygous for blood type A and the other is heterozygous for blood type B.

One parent is homozygous for blood type A and the other is homozygous for blood type O.

One parent has blood type AB and the other is homozygous for blood type O.

B) One parent is heterozygous for blood type A and the other is heterozygous for blood type B.

A heterozygous genotype for type A blood will be AO and for type B blood will be BO. Therefore, there is a 25% chance for a child to have genotype OO.

Which of these terms specifically means the intake and expulsion of air using the lungs?

Inspiration

Aeration

Ventilation

Oxygenation

C Ventilation

This term means the same as "breathing": the intake and expulsion of air using the lungs.

If an intensive property is independent of the amount of the material being measured, which of the following is an example of an intensive property?

Mass

Density

Volume

Length

B Density

Density is a ratio of material present in a given volume. Water will have the same density whether in a bucket or in a cup. It is independent of the amount of material. Therefore, it is an intensive property.

Which of the following options lists the correct order of events in a signaling pathway in a feedback loop used to maintain homeostasis?

Receptor → Effector → Integration → Stimulus → Response

Receptor → Stimulus → Integration → Response → Effector

Stimulus → Effector → Integration → Receptor → Response

Stimulus → Receptor → Integration → Effector → Response

D Stimulus → Receptor → Integration →Effector → Response

This answer is correct because a stimulus is the initial signal detected by a receptor. Information received is sent to the nervous system and an effector is used to achieve a response.

Which component of a phospholipid gives it nonpolar characteristics?

Glycerol molecule

Hydrogen bonds

Phosphate group

Carbon-hydrogen chains

D Carbon-hydrogen chains

Carbon-hydrogen chains do not have electronegative atoms and confer nonpolarity on the tails of phospholipids.

Which of the following chemical bonds is found within a molecule of ammonia, NH3, given that N is a highly electronegative element and has a valence of 5?

Nonpolar covalent bonds

Polar covalent bonds

Ionic bonds

Hydrogen bonds

Polar covalent bonds

Nitrogen is more electronegative than hydrogen, leading to an unequal sharing of electrons, which is the definition of polar covalent bonds.

Which of the following conditions might help a species to escape extinction in the face of changing environmental conditions, such as habitat destruction?

Extreme specialization

Small populations

Narrow ecological niches

Generalized distribution

D Generalization Distribution

A wide distribution will allow some members to survive detrimental changes.

Which of the following procedures is an appropriate negative control for testing the hypothesis that air contains bread mold spores?

Seal slices of bread in a container to minimize air contact.

Place slices of bread in a refrigerated environment.

Add ingredients to the bread recipe that will slow mold growth.

Expose a different mold-supporting medium to air.

Seal slices of bread in a container to minimize air contact.

A negative control verifies the testing environment. Here, the testing environment is the air. Therefore, excluding air from the bread in the container is the appropriate negative control.

A student placed 20 mL NaOH solution in a beaker and added 5 mL of HCl to it. Which of the following would happen when the two substances are mixed?

Hydrogen gas is released.

Carbon dioxide gas is produced.

The pH of the resultant solution is reduced.

The concentration of OH- ions is increased.

The pH of the resultant solution is reduced.

Acids donate H+ ions, which combine with OH- ions to make water. The lower the concentration of OH- ions, the lower the pH of the solution.

Which of the following describes the role of regulatory genes?

Regulatory genes control the expression of structural genes.

Regulatory genes catalyze chemical reactions.

Regulatory genes transfer information stored in DNA into proteins.

Regulatory genes code for membrane proteins.

Regulatory genes control the expression of structural genes.

Structural genes are transcribed into messenger RNA that assemble amino acids to produce functional proteins. Regulatory genes control the expression and activity of structural genes.

Which of the following bones is the large, fused bone of the upper jaw that contains teeth?

Maxilla

The maxilla refers to the large, fused bone of the upper jaw. It is formed by the fusion of the left and right maxillary bones.

Which of the following will likely happen in the case of blocked and injured ureters?

Frequent urination

No urine formation

Reduced flow of urine to the bladder

Bladder stretches due to an increase in urine volume

Reduced flow of urine to the bladder

Ureters are the tubes that carry urine from the kidneys to the bladder. When ureters are blocked or injured, the flow of urine to the bladder is reduced.

Which of the following statements correctly describes the relationship between genes and chromosomes?

Genes are DNA sequences found on chromosomes.

Chromosomes contain genes composed of amino acids.

Chromosomes are DNA sequences found on genes.

Genes contain chromosomes composed of amino acids.

Genes are DNA sequences found on chromosomes.

Genes are linear sequences of DNA on chromosomes, and they encode hereditary information that is transmitted to offspring.

Which of the following is the gland on a hair follicle that supplies the hair shaft and the skin with oily secretions?

Eccrine gland

Apocrine gland

Sebaceous gland

Ceruminous gland

Sebaceous gland

Sebaceous glands are flask-shaped with short ducts that open into hair follicles. They produce sebum, an oily secretion.

A blood pressure reading of 120/70 mm Hg refers to arterial pressures recorded during which of the following events?

Atrial contraction/ventricular contraction

Atrial contraction/ventricular relaxation

Ventricular contraction/ventricular relaxation

Ventricular relaxation/atrial relaxation

Ventricular contraction/ventricular relaxation

A blood pressure reading of 120 is peak arterial pressure during ventricular contraction (ventricular systole); 70 refers to minimal pressure during ventricular relaxation (ventricular diastole).

Which of the following is true of enzyme-catalyzed reactions?

The enzyme is not consumed in the reaction.

The substrate is produced in the active site.

The substrate remains unchanged during the reaction.

The enzyme raises the activation energy of the reaction.

The enzyme is not consumed in the reaction.

The enzyme lowers the energy required to initiate the reaction without being consumed in the process.