Bihar STET Paper 1 Science Mock Test - 4 - Bihar PGT/TGT/PRT MCQ

The cerebrum, the large, outer part of the brain, controls reading, thinking, learning, speech , emotions and planned muscle movements like walking.

The working of both smooth and cardiac muscles is involuntary while Skeletal or striated muscles move  according to our will  and are voluntary in action.

Answer:
The nucleous consists of protons and neutrons. Here is a detailed explanation of the components of the nucleous:
1. Protons:
- Protons are positively charged particles found in the nucleus of an atom.
- They have a mass of approximately 1 atomic mass unit (amu).
- The number of protons in an atom determines its atomic number, which defines the element.
2. Neutrons:
- Neutrons are neutral particles found in the nucleus of an atom.
- They have a mass similar to protons, approximately 1 amu.
- The number of neutrons in an atom can vary, resulting in different isotopes of an element.
3. Electrons:
- Electrons are negatively charged particles found in energy levels or shells outside the nucleus.
- They have a much smaller mass compared to protons and neutrons.
- The number of electrons in an atom is equal to the number of protons, ensuring overall neutrality.
Summary:
- The nucleus of an atom consists of protons and neutrons.
- Protons carry a positive charge and define the atomic number of an element.
- Neutrons are neutral particles and contribute to the mass of the atom.
- Electrons orbit around the nucleus in energy levels.

The solution on which the solute is more than the solvent .It is called concentrated solution. Concentrated solution is a solution that contains a large amount of solute relative to the amount that could dissolve.

At low pressure

Explanation: Boiling occurs when the vapor pressure of a liquid equals the external pressure. At lower pressures, the boiling point of water decreases. So, if the external pressure is reduced significantly (below atmospheric pressure), water can boil at room temperature. This phenomenon can be observed in a vacuum chamber, where the pressure is significantly reduced, allowing water to boil at room temperature.

DNA is the heridity material and genes which are located on chromosomes are made up of DNA.

Scattering of beam of light when passes through a solution is called tyndall effect. Colloidal solution shows the tyndall effect and scatter the beam of light.

The number of successful variations are maximised by the process of sexual reproduction. If we observe a field of sugarcane we find very little variations among the individual plants. But in a number of animals including human beings, which reproduce sexually, quite distinct variations are visible among different individuals.

Number of moles = Mass (in grams) / Molar mass.

Hypotonic solutions are the ones which have a lower concentration of solute than the inside the cell. Water diffuses into the cell to balance the solute concentration on either side (outside and inside) equal. Here the cell swells up due to entry of water by endosmosis. 

Number of Neutrons Released in the Fission of U-235
To determine the number of neutrons released in the fission of U-235, we need to understand the process of nuclear fission and the specific properties of U-235.
1. Nuclear Fission:
Nuclear fission is a process in which the nucleus of an atom is split into two or more smaller nuclei. This process releases a large amount of energy and additional neutrons.
2. U-235:
Uranium-235 (U-235) is a specific isotope of uranium that is commonly used as fuel in nuclear reactors. U-235 is fissile, meaning it can undergo nuclear fission when bombarded with low-energy neutrons.
3. Neutron Induced Fission of U-235:
When U-235 absorbs a low-energy neutron, it becomes unstable and splits into two smaller nuclei, releasing a large amount of energy and additional neutrons. These released neutrons can then go on to induce fission in other U-235 nuclei, creating a chain reaction.
4. Neutron Multiplication Factor (k):
The number of neutrons released in each fission event plays a crucial role in sustaining a chain reaction. The neutron multiplication factor, denoted as "k," represents the average number of neutrons produced in each fission event that go on to cause subsequent fissions.
5. Average Number of Neutrons Released in U-235 Fission:
The average number of neutrons released in the fission of U-235 is approximately 2.5. This means that, on average, each fission event of U-235 produces 2.5 neutrons that can induce fission in other U-235 nuclei.
6. Answer:
Based on the information provided, the correct answer is D: 3.0.

Baking soda is the common name for sodium bicarbonate, a chemical compound represented by the formula NaHCO3. It is widely used in baking and cooking as a leavening agent and for various household purposes.

Human activities are responsible for the disturbance of the balanced system of environment. Increasing human population is a major reason for cutting of trees. Vast tracts of forest had been cleared to make way for farmland and for making new houses, factories and infrastructure.
Production of more paper is also responsible for depletion of forest cover. Around 4 billion trees worldwide are cut down for paper every year.

When acids react with carbonates, such as calcium carbonate (found in chalk, limestone and marble), salt, water and carbon dioxide are made. In general: Acid + Metal carbonate Salt + Water + Carbon dioxide

Cinnabar is a toxic mercury sulfide mineral with a chemical composition of HgS. It is the only important ore of mercury. It has a bright red color that has caused people to use it as a pigment, and carve it into jewelry and ornaments for thousands of years in many parts of the world. Because it is toxic, its pigment and jewelry uses have almost been discontinued.

The peripheral nervous system facilitates communication between the central nervous system and other parts of the body.

Glass lid of solar cooker trapped the heat energy inside the box.

The atoms other than hydrogen and carbon are called heteroatoms.

The ovaries are the organs in the female reproductive system responsible for producing female gametes, known as eggs, as well as hormones like estrogen and progesterone. These hormones play a crucial role in triggering the development of secondary sexual characteristics in girls during puberty.

Directional growth movements in response to stimuli are termed as tropism.

Myopia is an eye defect in which light coming from an object gets focused slightly in front of the retina instead of directly falling on the retina. In this defect, a person cannot see distant objects, but can see the objects closer to him clearly. It is also known as Nearsightedness or Short Sightedness.
Myopia is caused due to the variation in the distance between the eye lens and retina. This distance increases when the eyeball gets elongated along its axis. This results in the object at a distance to appear blurry.
Thus, myopia is due to elongation of the eyeball.

The decomposers in an ecosystem play a crucial role in breaking down organic material and recycling nutrients. They are responsible for the decomposition process, which converts complex organic compounds into simpler inorganic forms that can be utilized by other organisms. Here is a detailed explanation of the role of decomposers in an ecosystem:
1. Convert organic material to inorganic forms:
- Decomposers such as bacteria, fungi, and certain types of insects break down dead plants, animals, and other organic matter.
- They release enzymes that break down complex organic compounds, such as proteins and carbohydrates, into simpler forms.
- This process releases inorganic nutrients, such as nitrogen, phosphorus, and carbon, back into the soil or water.
2. Release nutrients for use by other organisms:
- Decomposers play a crucial role in nutrient cycling by releasing essential elements from organic matter.
- These nutrients are then available for uptake by plants, which form the base of the food chain.
- In this way, decomposers help to maintain the overall balance and productivity of the ecosystem.
3. Improve soil fertility:
- Decomposers contribute to the formation of humus, a dark, organic-rich substance that improves soil fertility.
- As decomposers break down organic matter, they release nutrients that are absorbed by plants, promoting their growth.
- The organic matter also improves the soil's ability to retain water, nutrients, and support a diverse range of plant life.
4. Enhance ecosystem resilience:
- Decomposers play a vital role in recycling nutrients and breaking down dead organisms.
- This helps to prevent the accumulation of organic waste, which could lead to the release of harmful substances or the spread of diseases.
- By efficiently decomposing organic matter, decomposers contribute to the overall health and resilience of the ecosystem.
In conclusion, decomposers in an ecosystem are responsible for converting organic material into inorganic forms, releasing nutrients for use by other organisms, improving soil fertility, and enhancing the overall resilience of the ecosystem. Their role is essential in maintaining the balance and sustainability of the ecosystem.

NEP 2020 emphasizes providing equal opportunities for all genders and addressing gender-based discrimination in education.

Scaffolding process in education is a teaching strategy to expedite children's learning process. Using this method, teachers first demonstrate how to deal a problem, then go back and offer support as and when required. Once basic learning is done, they give prompts, ask questions, cues to make the child learn and build the concept on what he has already learned.

Teachers in multi-age classrooms are encouraged to use a range of teaching and assessment strategies to address the different ages of their students, implement flexible patterns of grouping, accommodate specific learning goals, engage all students in active participation, and promote a climate of respect for oneself and others.

In explore learning phase, the students investigate the topic more thoroughly. They need not be over-directed and need to find their way to the materials. They will need some direction and the teacher can circulate, asking important questions, listening to their interactions, and ensuring that they remain on task.
The 6 E's and S (Engage, Explore, Explain, Elaborate, Evaluate, Extend, and Standards) lesson plan format was developed by teachers, in consultation with faculty from schools of education, and is based on a constructivist model of teaching. The lesson plans are based on constructivist instructional models, with activities and sections of the plan designed to have the students continually add (or construct) new knowledge on top of existing knowledge.

The correct answer is Dynasty.

Key Points

• When members of the same family become rulers one after the other, the family is called a dynasty.
• An example of a dynasty is the Mauryan Dynasty.
• Wherein, there were three important rulers- Chandragupta, his son Bindusara, and Bindusara's son Ashoka.
• Alternative terms for dynasty are 'family', 'clan' etc.

 Thus, we can say that Dynasty is when members of the same family become rulers one after the other.

Additional Information

•  Empire is a political construct in which one state dominates over another state or a series of states.

The Rio de Janeiro Summit took place in the year 1992.

⇒ (2/1000) × (5/10)

⇒ (10/10000)

⇒ (1/1000) = 0.001

∴ 0.002 x 0.5 = 0.001

Given expression,

84% of 9600 + 48% of 6900 = ? + 50% of 2000

⇒ (84/100) × 9600 + (48/100) × 6900 = ? + (50/100) × 2000

⇒ 84 × 96 + 48 × 69 = ? + 50 × 20

⇒ 8064 + 3312 = ? + 1000

⇒ 11376 = ? + 1000

⇒ ? = 11376 - 1000 = 10376