Trên thước kẻ, đơn vị nhỏ nhất là gì?

Choose the best sequence to complete the sentence: "Oxygen is needed for (1) of humans, animals, and plants, and for (2) in life and production."

Thiết bị được hiển thị được sử dụng để tách các thành phần của hỗn hợp nào?

The sequence of images shows oil and water being combined, shaken, and then separating. What type of mixture formation is illustrated?

Look at the images: a gas stove flame, a kerosene lamp, an alcohol burner, and a coal fire. Which list correctly names the fuels used in order?

In many rural areas, people build biogas digesters to collect animal waste, which decomposes to produce a gas used for cooking or running generators. What is a main benefit of building such digesters?

Which material conducts electricity well?

Which set includes materials that are available in nature?

Which material cannot be recycled?

Fill in the blank in the statement: “A raw material is a material … that has not been processed and needs to be transformed to create a product.”

To maintain good health with a reasonable diet, what should we do?

Which of the following is not a fuel?

Coal is mined to supply thermal power plants to produce electricity. In this case, coal is called what?

Which is an efficient, economical way to use fuels?

Which group of foods below is a form of staple foods?

Which of the following is not a fossil fuel?

Among the foods below, which contains the most protein?

Which type of raw material below is almost nonrenewable?

Which type of fuel has a high heat output and burns completely most easily?

Using which form of energy causes the most air pollution?

Which of the following is considered a raw material?

Which crop below is not considered a staple food crop?

A mixture is formed from what?

Which of the following is a homogeneous mixture?

Which of the following is an emulsion?

Which of the following is a suspension?

Which item below is made of cells?

Look at the plant cell diagram where an arrow points to a part of the cell. Which part is indicated by the arrow?

How do animal cells differ from plant cells?

Fill in the blank: A cell is the unit of structure and ______ of all living organisms.

Observe the bacterium diagram. The arrow is pointing to which component of the cell?

Which statement is false?

What is the function of the cell membrane?

Which component controls all of the cell’s activities?

Refer to the labeled plant cell diagram. Which label indicates the cell membrane?

Refer to the labeled plant cell diagram. Which label indicates the component that controls all cell activities?

Based on the lifecycle diagram (cell → grows → mature cell → divides → two daughter cells), how many stages does cell reproduction go through?

What is the process called when a solid changes into a liquid?

Which process shows a chemical change?

Which natural phenomenon is caused by the condensation of water vapor?

A glowing matchstick is placed into a glass jar containing gas A, and the match bursts into flame. Identify gas A.

Which component of air is the main cause of the greenhouse effect?

To separate sand from water, which method should be used?

To separate cooking oil from water, which method should be used?

Consider the statements about cells: (1) All living organisms are made of cells. (2) In organisms, cells vary widely in size and shape. (3) Plant and animal cells have the same structure. (4) Cells perform many life functions of an organism. (5) Cells cannot reproduce. How many statements are correct?

Fill in the blank to complete the sentence: "Natural science is the branch of science that studies ..., natural laws, and their effects on human life and the environment."