FREE PISA Science Literacy Questions and Answers
BIODIVERSITY
Biodiversity refers to the variety of life forms present in a particular ecosystem or on Earth as a whole. It encompasses genetic diversity, species diversity, and ecosystem diversity. Which of the following factors is a significant threat to biodiversity?
Explanation:
Climate change poses a significant threat to biodiversity by altering temperature and precipitation patterns, leading to habitat loss, shifts in species distributions, and changes in ecosystems. This disruption can result in the decline or extinction of species, thereby reducing overall biodiversity.
PLANT PHOTOSYNTHESIS
Plants undergo photosynthesis, a process where they convert light energy into chemical energy, primarily in the form of glucose. This process occurs in chloroplasts, where chlorophyll captures light energy. Which of the following is a direct product of the light-dependent reactions of photosynthesis?
Explanation:
Oxygen is a direct product of the light-dependent reactions of photosynthesis, which take place in the thylakoid membranes of chloroplasts. During these reactions, water molecules are split into oxygen, protons, and electrons, releasing oxygen as a byproduct.
MOTION AND FORCES
Motion and forces are fundamental concepts in physics that describe the movement of objects and the interactions between them. According to Newton's first law of motion, an object at rest tends to stay at rest, and an object in motion tends to stay in motion unless acted upon by an external force. Which of the following scenarios best illustrates Newton's first law of motion?
Explanation:
Newton's first law of motion states that an object in motion tends to stay in motion unless acted upon by an external force. In the scenario described, the soccer ball is initially in motion due to being kicked across the field. Once the external force (the kick) ceases, the ball eventually comes to a stop on its own, demonstrating the tendency of objects in motion to remain in motion until acted upon by an external force.
BIRD MIGRATION
Bird migration is a seasonal large-scale movement of birds to and from their breeding grounds. Every year volunteers count migrating birds at specific locations. Scientists capture some of the birds and tag their legs with a combination of colored rings and flags. The scientists use sightings of tagged birds together with volunteers' counts to determine the migratory routes of birds.
Most migratory birds gather in one area and then migrate in large groups rather than individually. This behavior is a result of evolution. Which of the following is the best scientific explanation for the evolution of this behavior in most migratory birds?
Explanation:
Option A suggests that migrating in large groups provides protection from predators and increases the chances of survival and reproduction, which promotes the evolution of this behavior in migratory birds.
BIRD MIGRATION
Bird migration is a seasonal large-scale movement of birds to and from their breeding grounds. Every year volunteers count migrating birds at specific locations. Scientists capture some of the birds and tag their legs with a combination of colored rings and flags. The scientists use sightings of tagged birds together with volunteers' counts to determine the migratory routes of birds.
Most migratory birds gather in one area and then migrate in large groups rather than individually. This behavior is a result of evolution. What is the primary purpose of tagging migratory birds with colored rings and flags?
Explanation:
Tagging migratory birds with colored rings and flags allows scientists to track their movements and gather data on their migratory routes. By observing the sightings of these tagged birds along with counts conducted by volunteers, scientists can piece together the paths that migratory birds take during their seasonal migrations. This information helps researchers better understand bird migration patterns and behavior.
ELECTRICITY CONDUCTION
Electrical conductivity is a property of materials that describes their ability to conduct electric current. Metals are known for their high electrical conductivity due to the mobility of electrons in their atomic structure. Which of the following materials is an example of a good electrical insulator?
Explanation:
Glass is an example of a good electrical insulator because it does not allow electric current to flow easily through it. Unlike metals, which have loosely bound electrons that can move freely and conduct electricity, insulating materials like glass have tightly bound electrons, making it difficult for electricity to pass through them.
CHEMICAL REACTIONS
Chemical reactions involve the transformation of substances into new substances. During a chemical reaction, bonds between atoms are broken and new bonds are formed. Which of the following statements best describes an exothermic chemical reaction?
Explanation:
In an exothermic chemical reaction, energy is released to the surroundings in the form of heat or light. This results in an increase in temperature in the surrounding environment.
CELL STRUCTURE
Cells are the basic units of life and exhibit a variety of structures and functions. The cell membrane, also known as the plasma membrane, plays a crucial role in regulating the passage of substances into and out of the cell. Which of the following organelles is responsible for the synthesis of proteins within the cell?
Explanation:
The endoplasmic reticulum (ER) is responsible for the synthesis of proteins within the cell. It consists of a network of membranous tubules and sacs called cisternae, where protein synthesis occurs. There are two types of endoplasmic reticulum: rough endoplasmic reticulum (RER), which is studded with ribosomes and involved in protein synthesis, and smooth endoplasmic reticulum (SER), which lacks ribosomes and participates in lipid metabolism and detoxification.
ECOSYSTEM DYNAMICS
Ecosystems consist of living organisms interacting with each other and their physical environment. Trophic levels represent the position of organisms in a food chain or food web based on their feeding relationships. Which of the following organisms is likely to occupy the highest trophic level in a marine food chain?
Explanation:
Apex predators, such as large sharks or killer whales in marine ecosystems, occupy the highest trophic level. They are at the top of the food chain and typically have no natural predators. As such, they play a crucial role in regulating the populations of other organisms in the ecosystem and maintaining ecosystem balance.
ATOMIC STRUCTURE
Atoms are composed of subatomic particles, including protons, neutrons, and electrons. The atomic number of an atom corresponds to the number of protons in its nucleus. Which of the following elements has the same number of protons as carbon (C)?
Explanation:
The atomic number of carbon (C) is 6, which means it has 6 protons in its nucleus. Boron (B) also has 6 protons in its nucleus, making it the element with the same number of protons as carbon. Therefore, the correct answer is option D) Boron.
GENETIC INHERITANCE
In genetic inheritance, traits are passed down from parents to offspring through genes. In Mendelian genetics, traits are often inherited according to specific patterns. Which term refers to the genetic makeup of an individual for a particular trait?
Explanation:
The genotype refers to the genetic makeup of an individual for a particular trait, representing the combination of alleles inherited from the individual's parents. This genetic composition determines the observable characteristics, known as the phenotype, which may vary based on the specific alleles present.