ASVAB Science Test

Aerobic respiration occurs in

plants and animals. Aerobic respiration refers to oxygen-dependant respiration. Both plants and animals use oxygen to perform respiration.

Of these macromolecules, which are synthesized by ribosomes?

proteins. Ribosomes are organelles that help translate amino acids into proteins.

A kingdom consisting of eukaryotic, single-celled organisms is the

protista kingdom. Kingdom Protista includes all eurkaryotic, heterotrophic, unicellular organisms. Kingdom Plantae and Animalia contain multicellular organs. Kingdom Prokaryotae contains bacteria that are prokaryotic.

The gravity on the moon is about _____ of Earth's gravity.

1/6. The moon does not have as much mass as the earth. It is smaller, and the material of the moon is less dense than that of the earth.

A solution having a low concentration of hydrogen ions would best fit with which of the following pH ?

12. A low concentration of hydrogen ions results in a more basic or alkaline solution. Basic solutions have more hydroxyl ions. If the hydroxyl ion concentration is greater, the pH value will be higher. If the hydrogen ion concentration is greater, the pH value will be lower.

A typical human female has

22 pairs of chromosomes and two X chromosomes. The human female karyotype is 22 chromosomes with the 23rd pair, the sex chromosomes, consisting of two X chromosomes.

In humans, the trait for dimpled chins is dominant. Not having a dimpled chin is recessive. Two dimpled chin people who are heterozygous for this trait have children. What is the probability of dimpled versus non-dimpled offspring?

3/4 dimpled; 1/4 non-dimpled.

An atom with 8 protons, 12 neutrons, and 8 electrons has an atomic number of

8. The atomic number refers to the number of protons in the nucleus of each atom of an element.

Which of the following involves a chemical reaction?

A burning match changes from the chemicals causing combustion to the ash left after the burning is complete. The chemistry of the two is not similar. The examples using the water boiling, the ball bouncing, and the pencil breaking do not represent a chemical change; whether whole or separate the molecules maintain the same properties. The water and the pencil both represent a physical change, no chemical reaction or rearranging of molecules occurs. The ball bouncing is illustrating energy of motion.

Which of the following is considered a universal energy molecule for cells?

ATP. Adenosine triphosphate (ATP) is a nucleotide of adenine, ribose, and three phosphate groups. ATP acts as an energy carrier and drives virtually all energy-requiring cellular reactions.

The electrical circuit most likely used in everyday appliances is

Alternating current is the most common current used to supply electrical energy. It can be safely transferred at high voltages and over long distances.

Monocots and dicots are groups of

Angiosperms are a division of plants that are classified into two groups, monocots and dicots, which refer to seed leaf structure. (Monocots—one-seed leaves; dicots—two-seed leaves.)

A water shortage has resulted in restricted, small quantities of water to drink. Which hormone would increase in circulation as a result of this decreased water intake?

Anti-diuretic hormones work on renal tubules of the kidneys by making them reabsorb more water from the forming urine, and returning it to the bloodstream. Growth hormones stimulate body cells to grow and divide. Insulin lowers blood sugar levels. Oxytocin stimulates uterine contractions.

Color Vision results as a function of which of the following?

Cones are photoreceptors of the retinas that provide color vision and visual acuity.

Which one of the following is NOT a type of precipitation?

Fog. Precipitation may be defined as water in the solid or liquid state that falls on the earth. Common types of precipitation are the rain, snow, and hail. Fog is not a type of precipitation. It is formed by droplets of water vapor floating in the air near the ground. Rain, which falls from clouds, is the most common type of precipitation that takes place at temperatures above 0° C. Snow is precipitation in the solid form that occurs at temperatures below 0° C. Hailstones are associated with convectional currents and cumulonimbus clouds.

Igneous rock forms from

Igneous rock results from reactions from deep within the earth—molten magma cooling, solidifying and rising.

Which planet would most likely have a temperature of 800°F?

Mercury is the closest planet to the sun and would therefore sustain temperatures in excess of 800 °F

The process of cellular respiration in animal cells occurs in which organelle?

Mitochondria convert nutrients (glucose) into ATP by the chemical pathways of respiration.

The purpose of mitosis is

Mitosis is cell division of body cells. A parent cell divides into the daughter cells that are genetically identical to the parents. Meiosis generates sex cells (gametes) that are genetically different.

Which of the following respiratory gases are carried by a red blood cell?

O2 and CO2. The hemoglobin in red blood cells bind with O2 supplied by the respiratory system and carry the oxygen to body cells. It also picks up carbon dioxide as waste from body cells. H2CO3 is a weak carbonic acid, H2O is water, and CO is carbon monoxide, a toxic gas to humans. None are respiratory gases.

Which of the following materials could serve as a possible conductor?

Only silver has the metallic properties to allow electrons to pass or move freely within it. Wood, rubber, and resin do not conduct electrons and could serve as insulators.

Amoebas are single-celled organisms that eat by surrounding and engulfing its food. This process of eating is

Phagocytosis is a form of food ingestion used by amoebas and some white blood cells.

Which of the following receptors is present in the retina of the eye?

Photoreceptors. Photoreceptors are present in the retina of the eye. Stato-Acousto receptors are present in the ear. The mucous membrane is present in the inner lining of the nose. Chemoreceptors are present on the tongue.

Mammals, birds, amphibians and reptiles are examples of organisms belonging to which phylum?

Phylum Chordata represents only organisms having vertebrae (backbone).

A glass that falls off a table onto the floor illustrates

Potential energy is the capacity to do work. The potential energy of the glass is converted to movement, a form of kinetic energy, as it falls off the table.

A positive charge is characteristic of a(n)

Protons are positively charged particles in the atomic nucleus.

Which of the following is the result of a vitamin deficiency disease?

Rickets is a bone deformity disease caused by a vitamin D deficiency usually occurring early in life.

A stuntman misses a safety prop and falls, breaking his humerus. In what region of the body is the humerus found?

The humerus is found in the upper arm of the human skeleton.

A list of the elements in order of increasing atomic number is called the

The periodic table lists elements according to increasing atomic number and groups with similar properties.

_________ are not considered members of the basic food groups.

Vitamins and Minerals. Meats, dairy, and carbohydrates are all members of the major food groups. Vitamins and minerals are provided by assimilation of food from the food groups.

Which of the following cells are an important part of the immune system?

White blood cells are mobile components that help protect the body from bacterial, viral, and parasitic invaders, and toxins, and tumor cells. They initiate an inflammatory or immune response.

White light from the sun is

White light represents an expression of all colors combined.

A molecule is _________________________.

a combination of two or more atoms. Molecules are units of matter in which chemical bonds hold together two or more atoms of the same or different elements.

An uncharged particle in the atomic nucleus is

a neutron. Neutrons lack a charge. Protons are positively charged particles in the atomic nucleus. Electrons are negatively charged particles in the atomic nucleus. Ions are atoms with an electric charge.

Radioactivity of an element results from

a spontaneous disintegration of atomic nuclei. Radioactive elements are unstable and result in dissimilar numbers of protons and neutrons. They spontaneously lose subatomic particles and energy at known rates.

An archaeologist found an insect in a layer of clay, a fern in a layer of sand, a crustacean in a layer of mud, an amphibian in a layer of clay, and a bird in a layer of rock. The insect probably lived at the same time as the______________.

amphibian. Since the amphibian was also found in a layer of clay it probably existed around the same time as the insect. The bird, the fern and the crustacean were all found in different layers thus not making a correlation to living at the same time.

Human blood has a pH of about 7.4, if the pH were to change to 6.9 this indicates

an increase in acidity(The pH drops from 7.4 to 6.9. An increase of the proton (H+) concentration thus decreases the pH. A lower pH results in an increase in acidity.)

If an atom gains or loses an electron it is now

an ion. When atoms gain or lose electrons, the atom is no longer neutral and has a net charge that is either positive or negative. For example if an atom were to lose an electron there would now be an imbalance in favor of the protons. The atom would no longer be neutral but now carry a positive charge.

A control that reduces undesired pH fluctuations is a(n)

buffers. Buffers, or buffer systems are partnerships between weak acids and the base that forms when it dissolves in water. Buffers work to counteract slight shifts in pH. Acids are substances that that donate protons (H+) when dissolved in water. Bases are substances that accept protons forming hydroxyl (OH-) ions. Salts are substances that release ions other than H+ or OH- in solutions.

The uncontrolled chain reaction that takes place in a nuclear reactor is controlled by

cadmium rods. Nuclear fission is the process of disintegration of the heavy nuclei of radioactive atoms into nuclei of lighter atoms. Energy gets liberated in the form of gamma rays. This process is carried out in a reactor in a controlled way. The nuclei of the radioactive atoms disintegrate to give out many neutrons, which again disintegrate the heavy nuclei, causing a chain reaction. In a nuclear reactor, cadmium rods act as moderators and absorb the excess neutrons while allowing only a few to carry out the chain reaction in a controlled manner. Turbines convert nuclear energy into electrical energy. A water pump absorbs excess heat and a concrete wall protects the surroundings from harmful radiation.

Acid rain can cause which type of weathering?

chemical. Acid rain as well as acid fog, and acid snow represent precipitation that is much more acidic than normal, less than pH 5.6. Air pollutants such as sulfur dioxide and oxides of nitrogen can cause this excess acidity, which can chemically damage buildings, vegetation, aquatic life, soil etc.

The earth's orbit around the sun

completes every 365.25 days, completes every day. The earth follows an elliptical pattern as it orbits around the sun. The orbit is complete every 365.25 days.

When you sprinkle regular table salt on food, the salt will

dissociate by a decomposition reaction. The empirical equation for salt is Na+Cl-. When mixed with food, NaCl breaks into Na+ and Cl- ions.

Seismic activity as recorded by a seismograph is best associated with

earthquakes. The rupture of a fault precipitates an earthquake. As the earthquake begins, shockwaves are generated called seismic waves. These waves are analyzed and recorded by a seismograph.

Communication between neighboring cells is maintained through

endoplasmic reticulum. The function of the endoplasmic reticulum is to transport chemicals between and within cells. Therefore, it helps in communication between neighboring cells. Plasmodesma is a protoplasmic connection between cells. Golgi complex regulates the secretory pathway and controls trafficking of different types of proteins. Vacuoles store water, pigments, salts, and sugar. Therefore, choices B, C, and D are incorrect.

The mass of an element that combines with one part by weight of hydrogen is defined as its

equivalent weight. Equivalent weight is the mass of the element that combines with one part by weight of hydrogen or with one atom of hydrogen (1.008 parts by mass). When any monovalent element combines with one atom of hydrogen, its equivalent weight becomes equal to its atomic weight. A monovalent element such as chlorine combines with one atom of hydrogen to form a molecule of hydrogen chloride. So, in this case, the equivalent weight of chlorine is equal to its atomic weight: 35. Choices A, B, and D are incorrect because they differ in their basic definition. Atomic weight is the mass of an atom. Subatomic weight is the mass of a subatomic particle and the molecular weight is a sum of the masses of the atoms present in the molecule.

A nucleus is found in

eukaryotic cells. Eukaryotic is the general classification for all organisms that have a true nucleus and membrane-bound organelles.

If you wanted to obtain the greatest amount of energy from your daily diet without concern for any other factors, which component would you eat more of?

fats. Gram for gram, fat supplies more calories for energy than proteins, carbohydrates (starches), and vegetables.

Evidence of pre-existing life is most likely found in

fossils. Fossils are considered recognizable, physical records of life from the distant past.

Which state of matter has the greatest amount of kinetic energy?

gas. Gases have the most kinetic energy because molecules of gas move very quickly. They have no definite shape and fill all available space of a given volume.

Iodine added to table salt can help prevent which disease?

goiter. Iodine supplementation can help prevent goiter. Insufficient iodine can impair normal thyroid function resulting in goiter.

Atmospheric gases that allow light to enter the atmosphere but do not allow heat to exit create a

greenhouse effect. When atmospheric gases (greenhouse gases) such as carbon dioxide, methane, chloroflouorocarbons trap incoming and exiting solar radiation within the atmosphere, a gradual warming of the atmosphere occurs.

In the modern periodic table, the number of electrons in the outermost shell of an atom is equal to the

group number. The modern periodic table is based on the atomic number of elements. A modern periodic table has eighteen vertical columns called groups and seven horizontal rows called periods. Elements belonging to the same group have the same outer electronic distribution. The number of electrons in the outermost shell of an atom is equal to its group number.

A person who is a carrier for sickle cell anemia is genetically

heterozygous for the trait. Double dose sickle cell anemia results from two recessive alleles (ss). A person who is heterozygous dominant (Ss) is said to carry the sickle trait and may cause minor amounts of red blood cells to sickle. The possession of the dominant allele in the heterozygous state masks the ill affects of the recessive allele.

Polar molecules attracted to water are

hydrophilic. The term hydrophilic literally means "water loving." Polar substances such as water have areas of positive and negative charges. So any other polar substance will have a high affinity to the polar properties of water and will easily dissolve in water.

Chewing is necessary for digestion because it

increases the surface area of food exposed to enzymatic action. Chewing is a mechanical act whereby food can be broken into smaller pieces, mixed with saliva, and ultimately be prepped for faster, more efficient enzyme action.

As a magnetic pole is approached, the magnetic force

increases. Magnetic poles represent separate regions on a magnet where the force of attraction or repulsion is the greatest. Like poles repel, and unlike (opposite) poles attract. This magnetic force of attraction or repulsion increases the closer an object approaches the pole.

Diabetes mellitus results from the malfunction of

insulin. The correct answer is B. Diabetes mellitus results from the hyposecretion or hypoactivity of insulin.

One atom of Carbon has an atomic weight of 12 units; another atom of Carbon weighs 14 units. These two atoms are

isotopes. All atoms of an element have the same number of protons and electrons, but can differ in the amount of neutrons it possesses. If an atom of a certain element has more or less electrons than those having the most common number of neutrons, it is called an isotope.

Choose the correct order for taxonomic classification.

kingdom, phylum, class, order, family, genus, specie. This is the current taxonomic classification system, identifying organisms from their most general to most specific classifications.

Warm air has _________ atmospheric pressure than cold air.

less. Warm air is less dense than cool air and exerts less pressure on the atmosphere.

Sound waves move faster in _________ as a result of density.

liquids and solids. The speed of wave transmission depends on the properties of its medium. Liquids and solids have a greater density thus making the vibratory motion of sounds waves faster.

The appearance of deep holes and craters on the moon's surface are predominately the result of

meteoroids. Meteors colliding with the moon are among the prevalent current theories to explain its craterous surface. There is no concrete evidence that volcanic activity still occurs on the moon.

When a bus starts, its passengers experience a backward jerk because

of the inertia of the bodies. Inertia is the tendency of a body to maintain its state of rest or uniform motion, unless, acted upon by an external, unbalanced force. So, when the bus starts suddenly, its passengers experience a pseudo-force in the backward direction.

Roads along a curvature are banked to

reduce the centrifugal force on vehicles. A vehicle moves in a circular motion along a curved, leveled road. The vehicle is, therefore, subjected to a centrifugal force, which is a pseudo-force that acts on a body when it is in a non-inertial or accelerated frame of reference. The banked road provides a centripetal force that is necessary to keep the vehicle from skidding along the surface. The friction between the road and the tire also provides a centripetal force. Therefore, the road along a curvature is banked to reduce the centrifugal force on vehicles.

You are stranded in a desert. After some time you notice a pool of water off in the distance. You never reach the water and you realize it was a mirage. What is the most likely cause of this phenomenon?

refraction of light rays off the sand creating a false image. Refraction or refractory index refers to the ability to bend light rays. Illusory images can result from the bending of rays when passing from one medium to another. In this example the light rays from the sun were bent by the sand which causes the rays to move in many different directions causing the resulting effect of the mirage.

Two adaptations that help most of the desert plants to obtain and retain water are

shallow roots and small leaves. Plants in the desert tend to be widely scattered because of lack of water. The plants that survive compete for the small amount of water that is available. Some plants store water in their leaves, roots, and stem. They have shallow roots that spread out to take in surface moisture quickly from heavy dew and occasional rains. Desert plants also tend to have small leaves to reduce loss of water due to transpiration.

The bulk of the chemical breakdown and nutrient absorption occurs in the

small intestine. The small intestine is the site where the majority of digestive enzymes are secreted for the breakdown and usage of nutrients. The large intestine reabsorbs water and compacts undigested material into feces. The liver produces bile to emulsify fats and detoxify blood. The pancreas produces several digestive enzymes as well as the hormones insulin and glucagon.

Blood pressure is a measure of

systolic blood pressure over diastolic blood pressure. Blood pressure is a measure of heart contraction and relaxation. This causes the pressure within the arteries to rise and fall. Thus systolic pressure represents peak pressure during contraction and diastolic represents pressure during relaxation.

Exercise causes the respiratory (breathing) rate to increase because

the heart rate has increased. Exercise increases your body cells' need for oxygen because cells are using it faster. This in turn causes the heart to beat faster to circulate oxygen carrying red blood cells to body tissues.

The most important source of energy for our planet is

the sun. The radiant energy from the sun fuels many necessary processes that take place near the earth's surface. It is responsible for the circulation of the atmosphere and it powers photosynthesis in the biosphere.

The winds that blow from the subtropical high-pressure belt to the equatorial belt are known as the

trade winds. The winds that blow from the subtropical high-pressure belt to the equatorial belt are the trade winds. As they blow towards the equator, they become warmer and do not provide rainfall unless and until they meet a mountain barrier at right angles. The Westerlies are winds that blow from the subtropical high-pressure belt to the sub-polar belt. Polar winds blow from the polar high-pressure belt to the sub-polar low-pressure belt. Local winds originate from local temperature and pressure.

A weather front is created by

two distinct air masses meeting. A front is created when two different masses of air meet and do not mix and form boundaries. For instance, when a cold air mass from the north encounters a warm air mass from the south, the warm less dense air is pushed up. This encounter can cause specific cloud formations and weather patterns that may indicate rain. Barometric pressure is a measure of atmospheric pressure. Relative humidity is an index of moisture levels in the air relative to the maximum moisture that can be held at a certain temperature. Dew point is the measurement of temperature at which humidity condenses into a liquid.

The _______ that causes AIDS is _______.

virus; HIV

A cell containing 5% solute material is placed in a solution consisting of 10% solute. The net movement of ________ molecules will be ____ the cell due to osmosis.

water, out of. Osmotic movement of water is from high to low. The solute's concentration gradient drives the movement of water. The concentration of water in the cell is higher than the concentration of water the cells are placed in.