1.
Which is not made from cells?
Correct Answer
B. Sand
Explanation
Sand is not made from cells because it is a naturally occurring granular material composed of finely divided rock and mineral particles. Unlike living organisms such as mushrooms, dogs, and leaves, sand does not possess cellular structures or biological components. Sand is formed through processes such as erosion, weathering, and sedimentation, and does not have the characteristic features of living organisms.
2.
The first scientist to see animalcules, or tiny things was?
Correct Answer
D. Anton Van Leeuwenhoek
Explanation
Anton Van Leeuwenhoek is credited as the first scientist to observe and document animalcules, or microscopic organisms. He made significant advancements in the field of microscopy, constructing powerful microscopes that allowed him to observe and describe various microorganisms, including bacteria and protozoa. His discoveries were instrumental in the development of the field of microbiology and our understanding of the microscopic world.
3.
Which scientist discovered that all plants made up of living things?
Correct Answer
C. Mathias Schleiden
Explanation
Mathias Schleiden is credited with the discovery that all plants are made up of living things. He was a German botanist who, along with Theodor Schwann, formulated the cell theory, which states that all living organisms are composed of cells. Schleiden observed plant tissues under a microscope and concluded that plants are composed of individual cells. This discovery was a significant contribution to our understanding of the structure and function of plants.
4.
A structure that is found in plant cells but not in animal cells is?
Correct Answer
A. Cell wall
Explanation
The correct answer is cell wall. The cell wall is a rigid layer that surrounds the cell membrane in plant cells, providing support and protection. Animal cells do not have a cell wall, instead they have a flexible cell membrane that allows for movement and communication. The nucleus and nuclear membrane are present in both plant and animal cells, playing a role in genetic material storage and regulation.
5.
The grain-like organelles on which proteins are made up of are called?
Correct Answer
B. Ribosomes
Explanation
Ribosomes are the correct answer because they are the organelles responsible for protein synthesis in a cell. They are small, grain-like structures found either freely floating in the cytoplasm or attached to the endoplasmic reticulum. Ribosomes read the genetic information from the DNA and use it to assemble amino acids into proteins. They play a crucial role in protein synthesis, which is essential for various cellular functions and processes.
6.
The organelles on which proteins are made are called?
Correct Answer
C. Mitochondria
Explanation
Mitochondria are not the organelles on which proteins are made. Ribosomes are the organelles responsible for protein synthesis. They are found either freely floating in the cytoplasm or attached to the endoplasmic reticulum. Vacuoles are storage organelles and Golgi bodies are involved in processing and packaging proteins, but they are not directly involved in protein synthesis. Therefore, the correct answer is Ribosomes.
7.
The region between the cell membrane and the nucleus is called?
Correct Answer
D. Cytoplasm
Explanation
The region between the cell membrane and the nucleus is called the cytoplasm. It is a gel-like substance that fills the cell and contains various organelles, such as mitochondria and ribosomes. The cytoplasm plays a crucial role in cell metabolism, transport of molecules, and providing structural support to the cell. It also serves as a site for many cellular activities, including protein synthesis and cellular respiration.
8.
DNA and RNA are example of?
Correct Answer
B. Nucleic acids
Explanation
DNA and RNA are examples of nucleic acids. Nucleic acids are macromolecules that are essential for storing and transmitting genetic information in living organisms. DNA (deoxyribonucleic acid) carries the genetic instructions for the development, functioning, and reproduction of all known organisms. RNA (ribonucleic acid) plays a key role in protein synthesis and gene expression. Both DNA and RNA are composed of nucleotides, which are the building blocks of nucleic acids. Therefore, the correct answer is nucleic acids.
9.
Which type of organic compound includes sugar and starches?
Correct Answer
D. Carbohydrates
Explanation
Carbohydrates are the type of organic compound that includes sugar and starches. Carbohydrates are the main source of energy for the body and are made up of carbon, hydrogen, and oxygen atoms. They can be found in foods such as fruits, vegetables, grains, and dairy products. Sugars and starches are both examples of carbohydrates, with sugars being simple carbohydrates and starches being complex carbohydrates. Carbohydrates play a crucial role in providing energy, regulating blood sugar levels, and supporting various bodily functions.
10.
The movement of molecules from an area of greater concentration to an area of less concentration is called?
Correct Answer
B. Diffusion
Explanation
Diffusion is the movement of molecules from an area of greater concentration to an area of lesser concentration. This process occurs spontaneously and does not require any external energy input. It is driven by the random motion of molecules and leads to the equalization of concentration throughout a system. Diffusion is a fundamental process in various biological and physical phenomena, such as the exchange of gases in the lungs, the movement of nutrients across cell membranes, and the mixing of substances in a liquid.
11.
Plants use sunlight to make food in a process called
Correct Answer
B. pHotosynthesis
Explanation
Plants use sunlight to make food through a process called photosynthesis. During photosynthesis, plants convert sunlight, water, and carbon dioxide into glucose and oxygen. This process occurs in the chloroplasts of plant cells, specifically in the chlorophyll pigment. The energy from sunlight is captured by chlorophyll and used to convert carbon dioxide and water into glucose, which is then used as a source of energy for the plant. Oxygen is released as a byproduct of photosynthesis. Respiration, fermentation, and mitosis are not involved in the process of using sunlight to make food.
12.
Carbon Dioxide enters a plant through its?
Correct Answer
D. Stomata
Explanation
Stomata are tiny openings or pores on the surface of plant leaves and stems. They are responsible for the exchange of gases, including carbon dioxide and oxygen, between the plant and its environment. Carbon dioxide enters the plant through these stomata during the process of photosynthesis.
13.
The first stage of respiration takes place in the?
Correct Answer
C. Cytoplasm
Explanation
The first stage of respiration takes place in the cytoplasm. During this stage, known as glycolysis, glucose is broken down into two molecules of pyruvate. This process occurs in the cytoplasm of the cell, outside of the mitochondria. The pyruvate molecules then enter the mitochondria for further stages of respiration, including the Krebs cycle and electron transport chain. However, the initial breakdown of glucose occurs in the cytoplasm.
14.
One product of fermentation in yeast cells is?
Correct Answer
A. Alcohol
Explanation
During fermentation, yeast cells break down glucose in the absence of oxygen to produce energy. One of the byproducts of this process is alcohol, specifically ethanol. Therefore, alcohol is a product of fermentation in yeast cells.
15.
DNA replication occurs during?
Correct Answer
D. InterpHase
Explanation
DNA replication occurs during interphase. Interphase is the longest phase of the cell cycle and it is the period when the cell prepares for cell division. During this phase, the cell undergoes growth, carries out its normal functions, and replicates its DNA in preparation for cell division. Therefore, interphase is the correct answer as it is the specific phase in which DNA replication takes place.
16.
Chromatin condenses and forms rod-like structures during?
Correct Answer
B. PropHase
Explanation
During prophase, chromatin condenses and forms rod-like structures called chromosomes. This is an important step in cell division, as the condensed chromosomes allow for easier separation and distribution of genetic material to daughter cells. In anaphase, the chromosomes are already separated and moving towards opposite poles of the cell. In telophase, the chromosomes decondense and form chromatin again. In interphase, the cell is in a resting phase and the chromatin is not condensed. Therefore, the correct answer is prophase.
17.
The final stage of the cell cycle is called?
Correct Answer
B. Cytokinesis
Explanation
Cytokinesis is the correct answer because it is the final stage of the cell cycle. During cytokinesis, the cytoplasm of the cell divides, resulting in the formation of two daughter cells. This process completes the cell cycle and is essential for the growth and development of organisms. Interphase is not the final stage, but rather the stage where the cell prepares for division. Mitosis is a stage that occurs before cytokinesis, where the nucleus of the cell divides. Telophase is a substage of mitosis, not the final stage of the cell cycle.
18.
During DNA replication, adenine pairs with?
Correct Answer
A. Thymine
Explanation
During DNA replication, adenine pairs with thymine. This is because adenine and thymine are complementary base pairs in DNA. Adenine forms two hydrogen bonds with thymine, creating a stable base pair. This pairing is essential for the accurate replication of DNA, as each strand serves as a template for the synthesis of a new complementary strand. The pairing of adenine with thymine ensures that the genetic information is faithfully copied during DNA replication.
19.
The cell grows to its mature size during?
Correct Answer
D. InterpHase
Explanation
During interphase, the cell grows and carries out its normal functions. This is the longest phase of the cell cycle and is divided into three subphases: G1, S, and G2. During G1, the cell grows in size and synthesizes proteins and organelles. In the S phase, DNA replication occurs, resulting in the duplication of the cell's genetic material. Finally, during G2, the cell continues to grow and prepares for cell division. Therefore, interphase is the phase in which the cell grows to its mature size before undergoing mitosis.
20.
Most cases of cancer are caused by?
Correct Answer
A. Mutations
Explanation
Mutations are changes in the DNA sequence that can lead to the development of cancer. These changes can occur spontaneously or be caused by exposure to certain chemicals, toxins, or viruses. Mutations can disrupt the normal functioning of genes involved in cell growth and division, leading to uncontrolled cell growth and the formation of tumors. While radiation, tumors, and drugs can be factors that contribute to the development of cancer in some cases, mutations are the primary cause.
21.
The cytoplasm is the part of the cell in which?
Correct Answer
B. Proteins are made
Explanation
The cytoplasm is the part of the cell where proteins are made. This is because it contains various organelles, such as ribosomes, which are responsible for protein synthesis. Proteins are essential for various cellular functions and are involved in processes like cell signaling, enzyme activity, and structural support. Therefore, the cytoplasm plays a crucial role in protein production within the cell.
22.
A mutation that causes disease resistance in potatoes is a(n)?
Correct Answer
C. Helpful mutation
Explanation
A mutation that causes disease resistance in potatoes is considered a helpful mutation because it provides an advantage to the organism. In this case, the mutation allows the potatoes to resist diseases, which can improve their chances of survival and productivity. This beneficial trait can be passed on to future generations, leading to a population of potatoes with enhanced disease resistance.
23.
The porcess by which the number of chromosome is reduced by half to form sex cells is called?
Correct Answer
C. Meiosis
Explanation
Meiosis is the correct answer because it is the process by which the number of chromosomes is reduced by half to form sex cells. During meiosis, the genetic material is shuffled and recombined, resulting in genetic diversity. This process is essential for sexual reproduction and ensures that each offspring receives a unique combination of genes from their parents. Protein synthesis, heredity, and probability are not related to the reduction of chromosome number during the formation of sex cells.
24.
In the first step of protein synthesis what occurs?
Correct Answer
B. Messenger RNA is made using DNA as the pattern
Explanation
In the first step of protein synthesis, messenger RNA is made using DNA as the pattern. This process is called transcription, where the DNA sequence is copied into a complementary messenger RNA (mRNA) molecule. This mRNA molecule carries the genetic information from the DNA to the ribosomes, where it will be used as a template for protein synthesis. The mRNA molecule attaches to a ribosome in the subsequent step, allowing for the translation of the genetic code into a specific amino acid sequence.
25.
Gregor Mendel's work was foundation for the understanding why....
Correct Answer
D. Offspring have traits similar to those of their parents
Explanation
Gregor Mendel's work was the foundation for understanding why offspring have traits similar to those of their parents. Through his experiments with pea plants, Mendel discovered the principles of inheritance and established the concept of dominant and recessive traits. He observed that certain traits were consistently passed down from parents to offspring, and he developed the laws of segregation and independent assortment to explain how these traits are inherited. Mendel's work laid the groundwork for the field of genetics and provided a scientific explanation for why offspring resemble their parents in terms of inherited traits.
26.
In the genetic code, a group of three nitrogen bases codes for the attachment of a specific what?
Correct Answer
D. Amino acid
Explanation
In the genetic code, a group of three nitrogen bases, known as a codon, codes for the attachment of a specific amino acid. This process occurs during protein synthesis, where messenger RNA (mRNA) carries the genetic information from DNA to the ribosomes, and transfer RNA (tRNA) brings the corresponding amino acids to the ribosomes. The mRNA codon and tRNA anticodon pair up, ensuring that the correct amino acid is added to the growing protein chain. Therefore, the correct answer is amino acid.
27.
For codominant traits, heterozygotes have the phenotype of what?
Correct Answer
C. Neither the dominant nor recessive allele
Explanation
For codominant traits, heterozygotes have a phenotype that expresses both alleles equally. This means that neither the dominant allele nor the recessive allele is completely dominant over the other. Instead, both alleles are expressed and contribute to the phenotype of the individual. This results in a unique phenotype that is different from either the dominant or recessive phenotype.
28.
During meiosis, sex cells form when chromosome pairs are
Correct Answer
C. Seperated
Explanation
During meiosis, sex cells, also known as gametes, are formed through a process called chromosome separation. This occurs during the second division of meiosis, known as meiosis II. In this phase, the replicated chromosomes line up at the center of the cell and are pulled apart, or separated, to opposite poles of the cell. This ensures that each gamete receives only one copy of each chromosome, resulting in the formation of haploid cells that are genetically distinct from each other. Therefore, the correct answer is "separated."
29.
An organism's phenotype is its
Correct Answer
A. pHysical appearance
Explanation
The phenotype of an organism refers to its physical appearance, which includes observable characteristics such as color, shape, size, and behavior. It is determined by the interaction of the organism's genetic makeup (genotype) with environmental factors. While the genetic makeup and allele combination play a role in determining the phenotype, they alone do not fully define it. Therefore, the correct answer is physical appearance.
30.
An allele whose trait always shows up in an organism when the allele is present is a....
Correct Answer
B. Dominant allele
Explanation
A dominant allele is an allele that always expresses its trait in an organism, regardless of whether it is paired with another dominant allele or a recessive allele. This means that even if there is only one copy of the dominant allele present, it will still be able to determine the organism's phenotype. In contrast, a recessive allele only expresses its trait when it is paired with another recessive allele. Therefore, the correct answer is dominant allele.
31.
The most abundant gas in the universe is?
Correct Answer
A. Nitrogen
Explanation
Nitrogen is the most abundant gas in the universe because it makes up about 78% of Earth's atmosphere. It is also found in the atmospheres of other planets and in the interstellar medium. Nitrogen is an essential element for life and is used by plants and animals in various biological processes. Additionally, nitrogen is a major component of many important compounds such as proteins and nucleic acids.
32.
Most air pollution is caused by?
Correct Answer
D. The burning of fossil fuels
Explanation
The burning of fossil fuels is the main cause of air pollution. When fossil fuels such as coal, oil, and natural gas are burned for energy, they release harmful pollutants into the air, including carbon dioxide, sulfur dioxide, nitrogen oxides, and particulate matter. These pollutants contribute to the formation of smog, acid rain, and the greenhouse effect, leading to various health and environmental problems. Dust and pollen, erupting volcanoes, and acid rain can also contribute to air pollution, but they are not the primary sources like the burning of fossil fuels.
33.
Harmful substances in air, water or soil are called
Correct Answer
B. Pollutants
Explanation
Harmful substances that are present in the air, water, or soil are commonly referred to as pollutants. These pollutants can include various substances such as chemicals, toxins, gases, or even solid particles. They are considered harmful as they can have detrimental effects on the environment, human health, and ecosystems. Therefore, pollutants are the correct term used to describe these harmful substances in the given context.
34.
A barometer is used for?
Correct Answer
C. Air pressure
Explanation
A barometer is used to measure air pressure. It is a device that helps in determining the atmospheric pressure, which is the force exerted by the weight of the air molecules in the atmosphere. By measuring air pressure, a barometer can provide valuable information about weather patterns and changes. It is commonly used in meteorology and also in various industries such as aviation and agriculture, where knowledge of air pressure is important for decision-making and forecasting.
35.
The inner layer, or "weather layer," of the atmosphere is called?
Correct Answer
B. TropospHere
Explanation
The inner layer of the atmosphere is called the troposphere. It is the lowest layer of the atmosphere and extends from the Earth's surface up to about 10-15 kilometers. This layer is where weather occurs and where most of the Earth's air mass is located. It is also where temperature decreases with increasing altitude.
36.
Which layer of the atmosphere contains ozone, which protects the Earth from harmful ultraviolet rays?
Correct Answer
D. StratospHere
Explanation
The stratosphere is the correct answer because it is the layer of the atmosphere that contains the ozone layer. Ozone is a molecule made up of three oxygen atoms and it acts as a protective shield, absorbing and filtering out harmful ultraviolet (UV) rays from the sun. This is important because excessive UV radiation can cause skin cancer, cataracts, and other harmful effects on both humans and the environment. The presence of ozone in the stratosphere helps to protect the Earth's surface from these harmful UV rays.
37.
The "northern lights" or the Aurora Borealis are in what layer of the atmosphere?
Correct Answer
E. IonospHere
Explanation
The northern lights, also known as the Aurora Borealis, occur in the ionosphere. This is the layer of the Earth's atmosphere that is located between the mesosphere and the exosphere. The ionosphere is characterized by a high concentration of ions and free electrons, which are responsible for the colorful displays of the northern lights.
38.
Meteroids burn up in what layer of the atmosphere?
Correct Answer
A. MesospHere
Explanation
Meteoroids are small rocky or metallic objects that enter the Earth's atmosphere from outer space. As they travel through the atmosphere, they encounter air molecules and friction causes them to heat up and burn up. This burning process occurs mainly in the mesosphere, which is the layer of the atmosphere located between the stratosphere and the thermosphere. The mesosphere is characterized by low temperatures and high altitude, making it the ideal layer for meteoroids to burn up.
39.
As the density of air increase, its pressure...?
Correct Answer
C. Decreases
Explanation
As the density of air increases, its pressure decreases. This is because an increase in density means that there are more air molecules in a given volume, resulting in more collisions between the molecules. These collisions exert a force on the walls of the container, causing a decrease in pressure. Therefore, as the density of air increases, the pressure it exerts decreases.
40.
The sky looks blue because of .....
Correct Answer
C. Scattering
Explanation
The sky looks blue because of scattering. When sunlight passes through the Earth's atmosphere, the shorter blue wavelengths are scattered more than the longer red wavelengths. This scattering causes the blue light to be dispersed in all directions, making the sky appear blue to our eyes.
41.
The direct transfer of electromagnetic waves is called?
Correct Answer
D. Radiation
Explanation
Radiation is the correct answer because it refers to the direct transfer of electromagnetic waves. Unlike conduction, which involves the transfer of heat through direct contact, or convection, which involves the transfer of heat through the movement of fluids, radiation does not require a medium. It can occur through empty space and is responsible for the transfer of heat from the Sun to the Earth.
42.
On the Fahrenheit scale, the freezing point of water is?
Correct Answer
B. -32
Explanation
On the Fahrenheit scale, the freezing point of water is -32 degrees. This means that at this temperature, water will freeze and turn into ice. The Fahrenheit scale is commonly used in the United States and a few other countries. It is based on dividing the range between the freezing and boiling points of water into 180 equal intervals. The freezing point of water is marked as 32 degrees on this scale, and since the question asks for the freezing point in negative, the correct answer is -32.
43.
The upward movement of warm air and the downward movement of cool air is called a?
Correct Answer
C. Convection current
Explanation
Convection current is the correct answer because it accurately describes the upward movement of warm air and the downward movement of cool air. Convection is the transfer of heat through the movement of fluids (in this case, air) due to differences in temperature. As warm air rises, it creates a low-pressure area, causing cool air to flow in and replace it. This continuous cycle of upward and downward movement is known as a convection current.
44.
Wind direction is measured with a?
Correct Answer
A. Wind vane
Explanation
A wind vane is used to measure wind direction. It consists of a freely rotating arrow or pointer that aligns itself with the direction of the wind. This allows meteorologists and weather enthusiasts to determine the direction from which the wind is blowing. In contrast, a psychrometer is used to measure humidity, an anemometer is used to measure wind speed, and a thermometer is used to measure temperature. Therefore, the correct answer is wind vane.
45.
In the Northern Hemisphere, global winds that blow from southwest to the northeast are called...
Correct Answer
D. Prevailing westerlies
Explanation
The correct answer is prevailing westerlies. In the Northern Hemisphere, prevailing westerlies are the global winds that blow from southwest to northeast. These winds are responsible for the movement of weather systems across the mid-latitudes, including the United States and Europe. They play a crucial role in influencing the climate and weather patterns in these regions. Prevailing westerlies are characterized by their consistent direction and are caused by the Earth's rotation and the difference in heating between the equator and the poles.
46.
You compare the reading of a wet-bulb and dry-bulb thermometers to measure?
Correct Answer
D. Relative humidity
Explanation
The reading of a wet-bulb and dry-bulb thermometers is used to measure relative humidity. The wet-bulb thermometer is covered with a wet cloth, and as the water evaporates, it cools the bulb. The dry-bulb thermometer measures the ambient air temperature. By comparing the two readings, the difference between the wet-bulb temperature and the dry-bulb temperature can be used to calculate the relative humidity. This method is commonly used in weather forecasting and determining comfort levels in indoor environments.
47.
Clouds form when air is cooled to a....
Correct Answer
B. Dew point
Explanation
Clouds form when air is cooled to its dew point. The dew point is the temperature at which the air becomes saturated with water vapor and condensation begins to occur. As the air cools, it loses its ability to hold moisture, causing the water vapor to condense into tiny water droplets or ice crystals, forming clouds. Therefore, the dew point is the correct answer as it accurately describes the process of cloud formation.
48.
Hailstones form only in the type of cloud called a....
Correct Answer
C. Cumulonimbus
Explanation
Cumulonimbus clouds are known for their vertical development and are often associated with thunderstorms. These clouds have a large vertical extent, reaching high altitudes and producing intense updrafts. Hailstones form within cumulonimbus clouds when strong updrafts carry raindrops upward into extremely cold regions of the cloud, causing them to freeze and accumulate layers of ice. As the hailstone becomes too heavy for the updrafts to support, it falls to the ground as hail. Therefore, cumulonimbus clouds are the type of cloud in which hailstones form.
49.
A form of precipitation in which rain freezes as it falls through the air is called
Correct Answer
C. Sleet
Explanation
Sleet is a form of precipitation that occurs when raindrops freeze into ice pellets before reaching the ground. This happens when there is a layer of freezing air between the cloud and the surface, causing the raindrops to partially freeze. As a result, when the sleet reaches the ground, it falls as small ice pellets rather than liquid raindrops. This is different from freezing rain, which falls as liquid raindrops but freezes upon contact with cold surfaces. Snow is another form of precipitation, but it consists of ice crystals that fall from the clouds without melting. Hail, on the other hand, is formed in thunderstorms and consists of layered ice pellets.
50.
Which type of air mass brings cool, humid weather to the West Coast of the United States?
Correct Answer
C. Maritime polar
Explanation
Maritime polar air masses bring cool, humid weather to the West Coast of the United States. These air masses originate over the cold ocean waters of the North Pacific and move towards the coast, bringing in cool temperatures and moisture. The maritime polar air masses are responsible for the foggy and damp conditions commonly experienced in this region.