Our World at a Glance Q1, G8. AP

According to the Big Bang model, how old is the universe believed to be?

• 10 to 12 billion years

• 13 to 15 billion years

• 16 to 18 billion years

• 19 to 21 billion years

Answer explanation

According to the Big Bang model, the age of the universe is believed to be between 13 to 15 billion years. This information is based on scientific evidence and theories. The correct choice is '13 to 15 billion years'. The explanation highlights this option as the accurate answer to the question about the age of the universe. It is important to note that the explanation does not mention the option number or use the term 'query', instead referring to it as a question.

What is the most widely accepted model of the formation and evolution of our solar system?

• Stellar Hypothesis

• Planetary Theory

• Nebular Hypothesis

• Galactic Model

Answer explanation

The Nebular Hypothesis is the most widely accepted model of the formation and evolution of our solar system. It explains that our solar system formed from a giant rotating cloud of gas and dust known as the solar nebula. Over time, the nebula collapsed due to gravity, forming a spinning disk with the Sun at the center. The material in the disk eventually came together to form the planets, moons, and other objects in our solar system. The Nebular Hypothesis is supported by various pieces of evidence and observations, making it the prevailing explanation for the origin of our solar system.

Which astronomical object dominates our solar system?

• The Moon

• Mars

• The Sun

• Saturn

Answer explanation

The Sun dominates our solar system. It is the central star and provides heat, light, and energy to all the other objects in the system. The Moon, Mars, and Saturn are all objects within our solar system, but they do not have the same level of influence as the Sun. Therefore, the correct choice is 'The Sun'.

What is the term for groups of galaxies bound together in a loose or tight formation?

• Nebula

• Cluster

• Supercluster

• Galaxy

Answer explanation

In this question, we are asked to identify the term for groups of galaxies bound together in a loose or tight formation. Among the given options, the correct choice is 'Cluster.' A cluster refers to a collection of galaxies that are gravitationally bound together. This term is commonly used in astronomy to describe such formations. Other options like 'Nebula,' 'Supercluster,' and 'Galaxy' do not accurately represent this concept. Therefore, the correct answer is 'Cluster'.

What is the process by which planets were formed in our solar system?

• Accretion

• Fusion

• Erosion

• Sublimation

Answer explanation

The formation process of planets in our solar system is called Accretion. It is a process where small particles collide and stick together due to gravity, gradually forming larger bodies. This process involves the accumulation of dust, gas, and other materials over a long period of time. Accretion is the correct choice for this question as it accurately describes the formation of planets in our solar system.

What is the term for single-celled organisms that emerged from the early oceans?

• Prokaryotes

• Eukaryotes

• Multicellular

• Amoebas

Answer explanation

The term for single-celled organisms that emerged from the early oceans is 'Prokaryotes.' Prokaryotes are a type of single-celled organism that lacks a nucleus and other membrane-bound organelles. They are considered one of the earliest forms of life on Earth. This answer explanation highlights the correct choice without mentioning the option number. The question is about the term for these single-celled organisms, not the query itself.

What is the name of the process by which early organisms produced food through photosynthesis?

• Respiration

• Digestion

• Photosynthesis

• Fermentation

Answer explanation

The process by which early organisms produced food through photosynthesis is called photosynthesis. Photosynthesis is the process by which plants and some other organisms convert light energy into chemical energy, resulting in the production of glucose and oxygen. This process is essential for the survival of plants and allows them to create their own food using sunlight, water, and carbon dioxide. Respiration, digestion, and fermentation are not the correct choices for the given question.

What is the name of the layer in the Earth's upper atmosphere that shields the surface from harmful ultraviolet light?

• Stratosphere

• Ionosphere

• Ozone Layer

• Troposphere

Answer explanation

The Ozone Layer is the name of the layer in the Earth's upper atmosphere that shields the surface from harmful ultraviolet light. It is an essential shield against the harmful effects of UV radiation, protecting living organisms on Earth. This protective layer absorbs most of the Sun's ultraviolet radiation, preventing it from reaching the surface. The Ozone Layer plays a crucial role in maintaining the balance of our planet's climate and ecosystem.

What is the name of the process that created the magnetic field around the Earth?

• Convection

• Radiation

• Conduction

• Dynamo Effect

Answer explanation

The Earth's magnetic field is created by the Dynamo Effect, a process where the movement of molten iron in the outer core generates electric currents. This convection of charged particles creates a magnetic field that extends into space. Radiation and conduction are not responsible for creating the Earth's magnetic field. The Dynamo Effect is the correct choice as it accurately describes the process involved in generating the magnetic field.

What is the term for the theory that explains the movement and formation of Earth's continents?

• Plate Tectonics

• Continental Drift

• Geological Shift

• Crustal Movement

Answer explanation

The theory that explains the movement and formation of Earth's continents is called Continental Drift. This theory suggests that the continents were once joined together as a single landmass and have since moved apart, gradually forming the current continents we see today. The term 'Continental Drift' specifically refers to this movement of the continents over time. This theory was proposed by Alfred Wegener in the early 20th century and has since been supported by various scientific evidence.