Which of the following types of RNA carries amino acids to the ribosome during protein synthesis?

A. Messenger RNA

B. Ribosomal RNA

C. Transfer RNA

D. Small nuclear RNA

Answer Explanation:

Transfer RNA (tRNA) is a type of RNA molecule that carries amino acids to the ribosome during protein synthesis. Each tRNA molecule has a specific sequence of three nucleotides called an anticodon, which pairs with a complementary codon in the messenger RNA (mRNA) sequence. Each tRNA also carries a specific amino acid that corresponds to the codon it recognizes, allowing the ribosome to link the amino acids together in the correct order to form a protein.

In contrast, messenger RNA (mRNA) carries the genetic information from the DNA to the ribosome, where it serves as a template for protein synthesis. Ribosomal RNA (rRNA) is a component of the ribosome itself, where it helps to catalyze the formation of peptide bonds between amino acids. Small nuclear RNA (snRNA) is involved in splicing of pre-mRNA molecules during post-transcriptional processing.

Therefore, the Correct Answer is C.

Q #1: What is the difference between innate and adaptive immunity?

A. Innate immunity is present at birth while adaptive immunity is acquired after exposure to pathogens.

B. Innate immunity is specific to particular pathogens while adaptive immunity is nonspecific.

C. Innate immunity is mediated by antibodies while adaptive immunity is mediated by T cells.

D. Innate immunity provides long-term protection while adaptive immunity provides only short-term protection.

Answer Explanation

Innate immunity and adaptive immunity are two arms of the immune system that work together to protect the body from pathogens. Innate immunity is the first line of defense and is present at birth. It includes physical and chemical barriers such as the skin, mucous membranes, and antimicrobial peptides, as well as cells such as macrophages and natural killer cells that can quickly recognize and atack pathogens. Innate immunity is nonspecific, meaning it responds to a wide variety of pathogens in a similar way.

Adaptive immunity, on the other hand, is acquired after exposure to pathogens. It involves the production of antibodies and activation of T cells, which are specific to particular pathogens. Adaptive immunity takes longer to develop than innate immunity, but it provides a more specific and targeted response to pathogens. Once the adaptive immune system has been activated against a particular pathogen, it can provide long-term protection against future infections with that pathogen.

Option b) is incorrect because innate immunity is nonspecific while adaptive immunity is specific. Option c) is incorrect because antibodies are a part of adaptive immunity while T cells can be a part of both innate and adaptive immunity. Option d) is incorrect because adaptive immunity can provide long-term protection, while innate immunity provides immediate but short-lived protection.
Q #2: What is the difference between a physical change and a chemical change?

A. A physical change involves the rearrangement of atoms and molecules while a chemical change involves the formation of new substances with diﬀerent chemical properties.

B. A physical change involves the change of one state of mater to another while a chemical change involves the change of one substance into another.

C. A physical change involves the breaking of chemical bonds while a chemical change involves the breaking of intermolecular forces.

D. A physical change involves the release of energy while a chemical change involves the absorption of energy.

Answer Explanation

A physical change is a change that aﬀects the physical properties of a substance, but does not change its chemical identity. Physical changes include changes in state, such as melting or boiling, changes in shape or size, and changes in phase, such as the dissolution of a solid in a liquid. In a physical change, the atoms and molecules of the substance are rearranged, but no new substances are formed.

A chemical change, on the other hand, is a change that results in the formation of new substances with diﬀerent chemical properties. Chemical changes involve the breaking of chemical bonds between atoms and the formation of new bonds to create new compounds. Chemical changes are usually accompanied by a change in color, the formation of a gas or a solid, or the release or absorption of energy.

Overall, the main diﬀerence between a physical change and a chemical change is that a physical change only aﬀects the physical properties of a substance while a chemical change results in the formation of new substances with diﬀerent chemical properties.
Q #3: What is the name of the joint that allows for rotation of the arm at the shoulder?

A. Elbow joint

B. Hip joint

C. Knee joint

D. Shoulder joint

Answer Explanation
Q #4: Which of the following units is used to indicate length?

A. kg

B. L

C. s

D. m

Answer Explanation

The unit used to indicate length is the meter (m). It is the base unit of length in the International System of Units (SI).
Q #5: What is the name of the genetic disorder caused by the presence of an extra chromosome 21?

A. Turner syndrome

B. Klinefelter syndrome

C. Down syndrome

D. Huntington's disease

Answer Explanation

Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21. It is also known as trisomy 21, because aﬀected individuals have three copies of chromosome 21 instead of the normal two.

The extra chromosome 21 in Down syndrome occurs due to a random error in cell division, which leads to the production of an abnormal gamete (egg or sperm) with an extra copy of the chromosome. When this gamete fuses with a normal gamete during fertilization, the resulting zygote has 47 chromosomes instead of the usual 46, and develops into a fetus with Down syndrome.

Down syndrome is characterized by a range of physical and intellectual symptoms, including developmental delays, intellectual disability, distinctive facial features, heart defects, and increased risk of certain medical conditions such as leukemia and Alzheimer's disease. However, the severity and expression of these symptoms can vary widely among aﬀected individuals.
Q #6: Which of the following is a chemical property of a substance?

A. Density

B. Melting point

C. Boiling point

D. Reactivity with acid

Answer Explanation

Chemical properties are characteristics of a substance that describe its ability to undergo a chemical change or reaction with another substance.

Reactivity with acid is a chemical property because it describes how a substance will react with an acid to produce a new substance. Density, melting point, and boiling point are physical properties that describe how a substance behaves under certain conditions but do not involve a chemical change or reaction.
Q #7: What is the primary pigment responsible for photosynthesis in plants?

A. Chlorophyll a

B. Chlorophyll b

C. Carotenoids

D. Anthocyanins

Answer Explanation

Chlorophyll a is the primary pigment responsible for photosynthesis in plants. It is a green pigment that is essential for capturing light energy from the sun and converting it into chemical energy that can be used by the plant. Chlorophyll a absorbs light most efficiently in the blue and red parts of the spectrum, and reﬂects green light, giving plants their characteristic green color

Chlorophyll b is another type of chlorophyll that is also involved in photosynthesis, but it is not as abundant as chlorophyll a. Chlorophyll b absorbs light most efficiently in the blue and orange parts of the spectrum and reﬂects yellow-green light.

Carotenoids are pigments that are present in many plants and are involved in photosynthesis as well as protecting the plant from damage caused by excess light. Carotenoids are responsible for the orange, yellow, and red colors of many fruits and vegetables.

Anthocyanins are pigments that give plants their red, purple, and blue colors. While they are not directly involved in photosynthesis, they play a role in atracting pollinators and protecting the plant from damage caused by UV radiation.
Q #8: What is the largest organ in the human body by surface area?

A. Brain

B. Heart

C. Liver

D. Skin

Answer Explanation

The largest organ in the human body by surface area is the skin. It covers the entire external surface of the body and has an average surface area of about 20 square feet in adults.
Q #9: Which of the following types of RNA carries amino acids to the ribosome during protein synthesis?

A. Messenger RNA

B. Ribosomal RNA

C. Transfer RNA

D. Small nuclear RNA

Answer Explanation

Transfer RNA (tRNA) is a type of RNA molecule that carries amino acids to the ribosome during protein synthesis. Each tRNA molecule has a specific sequence of three nucleotides called an anticodon, which pairs with a complementary codon in the messenger RNA (mRNA) sequence. Each tRNA also carries a specific amino acid that corresponds to the codon it recognizes, allowing the ribosome to link the amino acids together in the correct order to form a protein.

In contrast, messenger RNA (mRNA) carries the genetic information from the DNA to the ribosome, where it serves as a template for protein synthesis. Ribosomal RNA (rRNA) is a component of the ribosome itself, where it helps to catalyze the formation of peptide bonds between amino acids. Small nuclear RNA (snRNA) is involved in splicing of pre-mRNA molecules during post-transcriptional processing.
Q #10: What are the steps involved in the scientific method?

A. Observation, hypothesis, prediction, experimentation, analysis, conclusion.

B. Hypothesis, observation, prediction, experimentation, analysis, conclusion.

C. Prediction, observation, experimentation, analysis, conclusion, hypothesis.

D. Observation, data collection, analysis, experimentation, hypothesis, conclusion.
Answer Explanation

The scientific method is a systematic approach used to answer questions or test hypotheses about the natural world. The steps involved in the scientific method are:
1. Observation: This is the first step in the scientific method. It involves observing a phenomenon or a problem and gathering information about it.
2. Hypothesis: After making an observation, a scientist forms a hypothesis, which is a tentative explanation for the phenomenon or problem.
3. Prediction: Based on the hypothesis, the scientist makes a prediction about what will happen in an experiment or what they will observe.
4. Experimentation: The scientist designs and conducts an experiment to test the hypothesis and prediction.
5. Analysis: The data collected from the experiment are analyzed to determine if they support or refute the hypothesis.
6. Conclusion: Based on the analysis of the data, the scientist draws a conclusion about whether the hypothesis is supported or refuted.
Option b) is incorrect because it starts with hypothesis before observation. Option c) is incorrect because prediction comes before experimentation. Option d) is incorrect because hypothesis comes after observation and data collection.