Free Teas Science Practice Questions
The ATI teas Science exam is one of the largest sections of the ATI TEAS exam (with 31% of it), and one of the most difficult for many test takers. With topics like Human Anatomy & Physiology, Chemistry, Biology, and Scientific Reasoning there is a lot to cover. Let's look at a few examples, starting with Human Anatomy & Physiology.
Anatomy and Physiology:
Question no. 1 – skeletal system:
Which of the following is an irregularly shaped bone?
A) Sacrum
B) Fibula
C) Sternum
D) Incus
Answer & Explanation
The correct answer is (A).The sacrum is an irregular bone at the base of the spine. The fibula is a long bone found in the leg. The sternum is a flat bone at the center of the chest. The incus is a sesamoid bone in the ear.
TEAS Science Tip - Anatomy:
Utilizing visual aids such as anatomical diagrams, charts, and models can be helpful for both understanding and explaining human anatomy.
Given the extensive memorization required for answering questions related to human anatomy, incorporating visual aids into your practice can significantly improve your understanding.
Consider using these visual aids both before and after formulating your responses, as they can facilitate a better grasp of those concepts
Question no. 2 – Renal System:
Which of the following statements regarding glucose renal transport is incorrect?
A) Glucose reabsorption depends on sodium reabsorption.
B) Increased glucose reabsorption subsequently increases renal blood flow and glomerular filtration rate.
C) The urinary glucose excretion rate equals the subtraction of the filtration and secretion rates from the reabsorption rate.
D) The renal glucose reabsorption mechanism resembles intestinal glucose reabsorption in the jejunum.
Answer & Explanation
The correct answer is (C).
In order to calculate glucose excretion rates, the following equation should be used: Urinary excretion rate = filtration rate–(reabsorption rate + secretion rate). In answer (C), the places of the filtration rate and reabsorption rate are changed.
Answer (A) describes a correct statement because glucose is transported through a symporter, conjugated to the transport of sodium. Answer (B) presents a true statement. Increased glucose delivery to the tubules causes them to reabsorb excess sodium along with glucose. This, in turn, decreases delivery of sodium chloride to the macula densa, activating a tubuloglomerular feedback which subsequently increases the renal blood flow and GFR.
Answer (D) states a true statement, since both intestinal and renal glucose transports are mediated by the same type of symport proteins. Therefore, answer (C) contains an incorrect statement, and it is, therefore, the correct answer.
Question no. 3 – physiology:
Which of the following does not affect the binding affinity of oxygen to hemoglobin?
A) The levels of hemoglobin within the erythrocyte cells
B) The allosteric regulation of hemoglobin
C) The pH level
D) The partial pressure of oxygen
Answer & Explanation
The correct answer is (A).
Hemoglobin is a protein, which binds and transports oxygen from the lungs to the tissues. In the tissues, hemoglobin releases the oxygen and binds the carbon dioxide; it is responsible for the clearance of about 15-20% of the carbon dioxide molecules.
This protein is also responsible for maintenance of the pH within the tissues by binding the helium ions, which in response, affects the pH. The binding of helium ions to the protein reduces the binding affinity of hemoglobin to oxygen.
The partial pressure of oxygen and the partial pressure of carbon dioxide affect the binding affinity of oxygen to hemoglobin by conformation changes of the protein. Hemoglobin consists of four units. Each unit can bind the oxygen via the heme group.
The binding has an allosteric effect on the other binding sites; the binding of each oxygen molecule increases the affinity of the other sites to oxygen; this is also called cooperative binding. The binding affinity is not affected by the levels of hemoglobin proteins in the blood.
The section comprises 51 questions to be answered in just over an hour (63 minutes). The ATI TEAS Science section is comprised of three topics:
· Human Anatomy & Physiology, (18 items, 40% of the Science section)
· Biology, (9 items, 20% of the Science section)
· Chemistry, (9 items, 20% of the Science section)
· Scientific Reasoning (9 items, 20% of the Science section)
· An additional 6 items are included as pretest items
The Science section can be many applicants' most daunting part of the TEAS Test. Use our detailed study
guides and thoroughly read the questions' explanations to learn the complex subject matter and solve full-length simulation tests to improve your performance under time pressure.
Human Anatomy and Physiology serve as the basic foundations for medicine – and therefore comprise a major component of the TEAS Science test. However, the section includes other topics – which serve as the roots of medical and life sciences. Let's continue with Chemistry questions, which include Chemical Reactions and Bonds, Acids and Bases, Stoichiometry, and States of Matter, among else.
Chemistry:
Question no. 4 - acids and bases:
Sodium hydroxide (NaOH) is added to acetic acid. Which of the following is expected to be the nature of the resulting solution?
A) Neutral
B) Basic
C) Depends on the amount of added NaOH
D) Depends on the acid’s pH prior to the addition of NaOH
Answer & Explanation
The correct answer is (C).
Adding a strong base to a weak acid is called titration (as is adding a strong acid to a weak base). Each weak acid or base has its own titration curve, with the solution's pH versus the amount of added strong base or acid. The curve, which is empiric, gives the solution's pH at any amount of added base or acid.
For example, using the acetic acid's titration curve below, you can see that after adding 20 ml of NaOH, the solution is still acidic, and after adding 30 ml of NaOH, the solution becomes basic.
TEAS Science Tip - Chemistry:
The previous question can provide two valuable insights:
1. In certain questions, creating a visual representation, such as a graph like the one provided in the previous explanation, can simplify the problem-solving process. We recommend you do so, as it can be "worth the time." This visual doesn't have to be accurate or aesthetically pleasing; it simply needs to serve as a helpful tool.
2. When you don’t understand some sentences or rules, try to substitute real numbers, and then check the sentence. This approach can help you determine whether a sentence is correct or incorrect.
Question no. 5 – chemical reactions:
The proposed mechanism for the reaction A → D consists of 3 steps. The reaction profile diagram that describes this mechanism is given below:
Which one of the following statements is true?
A) The overall reaction is endothermic.
B) The reaction B → C is the fastest step of the overall reaction.
C) The reaction B → C is the rate-determining step of the overall reaction.
D) There are two intermediates and three transition states in the overall reaction.
The correct answer is (D).
The graph describes a reaction process of reactant/substrate A to new product D. Reactant A is less stable than product D as on the y axial it has a reduced value. The peaks describe activated complexes which are less stable than their product and B and C describe the transitional state, which is lower than the activated complex in the energy but is less stable than the product regarding the energy cost.
Specifically, the activated complex is a molecular structure, formed through collisions, which either dissociates back into the reactants or forms products and is completely unstable. The transition states are the points of greatest energies along the reaction profile, and the intermediate is a more stable species that takes part in a reaction mechanism but is not a reactant and does not occur in the reaction rate law. According to the profile above, the reaction mechanism consists of three transition states (points of maximum energy) and two intermediates (points B and C).
Therefore, answer (D) is the correct answer. Note the activation energy is the minimum energy of collisions required for a chemical reaction to occur. Thus, it is an energy barrier that separates the reactants from the products. Only a fraction of all colliding molecules have sufficient kinetic energy to overcome it. On a reaction profile, the activation energy of a forward reaction is the energy difference between an activated complex and a reactant.
Answer (A) is incorrect because the enthalpy change (ΔH) of the overall reaction equals the energy difference between the products and reactants. Because the products have lower energy than the reactants, ΔH < 0, the reaction is exothermic and not endothermic. Answer (B) is incorrect because reaction C → D, and not B → C, is the fastest step of the overall reaction because it has the lowest activation energy. Answer (C) is incorrect because reaction A → B, and not B → C, is the rate-limiting step of the overall reaction because it has the greatest activation energy.
Notice: The chemistry questions, as well as the following Biology questions, are new, and have been added to TEAS 7, replacing the Life & Physical Sciences section on TEAS.
Next is Biology. Key areas here include heredity, DNA, mitosis and meiosis, macromolecules, and cellular biology. Next is Biology. Key areas here include heredity, DNA, mitosis and meiosis, macromolecules, and cellular biology.
Biology:
Question no. 6 – mitosis and meiosis
Which of the following occurs in mitosis but not in meiosis?
A) The mother cell divides once into two daughter cells
B) DNA replication
C) Cross-over in homologous chromosomes
D) Divides from a reproductive cell
Answer & Explanation
The correct answer is (A).
In mitosis, which occurs in somatic cells (regular cells with 2n chromosomes that are not reproductive cells), the chromosomal material is duplicated (to become 4n) and one mother cell divides once into two diploid (2n) daughter cells. In meiosis, which occurs in reproductive cells (2n), after the duplication of the chromosomal material (4n), one mother cell divides twice into four haploid (n) daughter cells.
DNA replication occurs in meiosis as well as in mitosis. Cross-over in homologous chromosomes, the process in which the genetic information stored on two homologous chromosomes is "shuffled," occurs in meiosis and not in mitosis.
TEAS Science Tip - Biology:
Both mitosis and meiosis consist of a series of stages. We recommend you familiarize yourself with the key stages of each process: in mitosis, these stages include prophase, metaphase, anaphase, and telophase, while meiosis include meiosis 1 and meiosis 2. You can use visual aids such as charts and graphs to extend your knowledge. You will see that knowing the sequence of events on these stages and the specific changes that occur, such as chromosome duplication, alignment, and separation, will enable you to provide accurate and detailed explanations when answering questions about this process.
Memorizing in the TEAS Science section is a big to your success in the exam. Beginning practicing now will help you to memorize more details and crucial information for the exam.
Question no. 7 – cellular biology:
Which of the following is characteristic only to eukaryotes and not to prokaryotes?
A) Histones
B) Ribosomes
C) Genetic recombination
D) Flagella
Answer & Explanation
The correct answer is (A).
Histones are proteins found in eukaryotic cell nuclei. They package and order DNA into nucleosomes.
Prokaryotes do not produce these proteins as their DNA is a single circular chromosome. Answer (B) is incorrect because both organism types have ribosomes, only in different sizes. Eukaryotic ribosomes are larger.
Answer (C) is incorrect because both organisms can genetically recombinate; prokaryotes through conjugation, and eukaryotes through sexual reproduction. Answer (D) is incorrect because species of both classes can have flagella on their membrane surface although they differ in composition.
Let's continue to the science question type covered in this TEAS Science Free Practice Test – Scientific Reasoning. While it may be less trivial than previous questions – it is essential for medical staff to be well-educated in this field. Questions include topics like Data Interpretation, Scientific Measurement, and Critical Thinking
Scientific Reasoning:
Question no. 8 – the scientific method:
Scientists experimented to examine whether a new medicine they developed for reducing blood pressure is better than an old medicine that already exists in the market.
They divided their participants into four groups: the first group took the new medicine, the second group took the old medicine, the third group took a pill without any active ingredient, and the fourth group received no treatment.
The blood pressure of the four groups was measured before the treatment and again after two weeks of treatment, and the difference was calculated for each group.
Which statements regarding the experiment are true?
A) The dependent variable is the blood pressure after the treatment.
B) The purpose of the second group is to examine a placebo effect.
C) The independent variable is the treatment type.
D) The fourth group is a control group.
Answer & Explanation
The correct answers are C and D.
In a scientific experiment, the independent variable is the variable that is changed or controlled to examine its effects on the dependent variable. In this experiment, the effect of different types of treatment (new medicine, old medicine, pill with no active ingredient, no treatment) was examined, so this is the independent variable, and answer C is correct.
A control group is a group that is similar in its characteristics to the experimental groups, but it does not receive the tested treatment. The scientists expect to see no change in the control group so that they can prove that the treatment is what caused the change in the experimental group. In this experiment, the fourth group did not receive any treatment, so it is a control group and answer D is correct.
Answer A is incorrect because the blood pressure after the treatment is not the dependent variable in the experiment. The dependent variable is the difference between the blood pressure before the treatment and the blood pressure after the treatment.
Answer B is incorrect. The placebo effect is a phenomenon in which the condition of a patient seems to improve after taking an inactive treatment, due to the belief that they are taking a real medicine. In this experiment, the second group received the old medicine, and the third group received an inactive pill, so the third's group purpose is to examine a placebo effect, and not the second's group.
TEAS Science Tip – Scientific Reasoning:
For complex, overwhelming questions, try a two-step approach to avoid getting overwhelmed:
1. Read the text to understand its main ideas.
2. For each statement, go back to the text to check its accuracy.
This strategy improves accuracy by focusing on relevant information without repeatedly reading the entire text to memorize every detail.
Question no. 9 – measurements and tools:
During a lab lesson, a chemistry student was asked to transfer exactly 2 milliliters of a solution from a test tube that contains 20 milliliters of the solution to another test tube. Which of the following tools should the student use?
A) Graduated cylinder
B) Thermometer
C) Volumetric pipette
D) Meter stick
Answer & Explanation
The correct answer is C.
A volumetric pipette is a laboratory tool that is used for transferring small volumes of liquids with a very high degree of accuracy. Therefore, the student should use a volumetric pipette, and answer C is correct.
Answer A is incorrect because a graduated cylinder is used for measuring greater volumes of liquids, and not for transferring small volumes of liquids.
Answer B is incorrect because a thermometer is used to measure temperature and not volume.
Answer D is incorrect because a meter stick is used to measure length and not volume.
Prepare For The Full TEAS Test
While the TEAS Science exam may be the largest component of the TEAS exam, it is certainly not the only one. Our experts at TestPrep-Online have comprised a comprehensive preparation course for all of the TEAS sections which includes full TEAS Science Practice tests, as well as Free Practice Test so you can get a better understanding of what the test includes.
