Grade 8 Biology Quiz

What is the basic unit of life?

• atom

• organism

• cell

• molecule

Name the organelle known as the 'powerhouse' of the cell.

• vacuole

• mitochondria

• nucleus

• ribosomes

Explain the process of osmosis.

• Osmosis is the movement of glucose molecules from an area of high concentration to an area of low concentration through a selectively permeable membrane.

• Osmosis is the movement of water molecules from an area of high concentration to an area of low concentration through a selectively permeable membrane.

• Osmosis is the movement of air molecules from an area of low concentration to an area of high concentration through a selectively permeable membrane.

• Osmosis is the movement of water molecules from an area of low concentration to an area of high concentration through a selectively permeable membrane.

What is the function of the cell membrane?

• Controls the movement of substances in and out of the cell

• Provides energy to the cell

• Regulates body temperature

• Stores genetic information

Define homeostasis and provide an example.

• Homeostasis is the ability of an organism to maintain a stable internal environment despite changes in the external environment. An example of homeostasis is the regulation of body temperature in humans.

• Homeostasis is the ability of an organism to change its internal environment based on the external environment. An example is the growth of plants.

• Homeostasis is the inability of an organism to maintain a stable internal environment. An example is the regulation of blood sugar levels in humans.

• Homeostasis is the ability of an organism to maintain a stable external environment despite changes in the internal environment. An example is the migration of birds.

What are the three main parts of a cell?

• cell wall, mitochondria, vacuole

• chloroplast, Golgi apparatus, endoplasmic reticulum

• ribosome, lysosome, peroxisome

• cell membrane, cytoplasm, nucleus

Explain the difference between active and passive transport.

• Active transport requires no energy, while passive transport requires energy

• Active transport moves substances with the concentration gradient, while passive transport moves substances against the concentration gradient

• Active transport is faster than passive transport, while passive transport is slower

• Active transport requires energy to move substances across the cell membrane, while passive transport does not require energy and relies on the concentration gradient.

How do cells maintain a stable internal environment?

• Cellular respiration

• Photosynthesis

• Mutation

• Homeostasis

What is the function of the nucleus in a cell?

• Energy production in the cell

• Transport of nutrients in the cell

• Storage of waste in the cell

• Control center of the cell

Describe the structure of a plant cell and its functions.

• The structure of a plant cell includes a cell wall, cell membrane, cytoplasm, nucleus, chloroplasts, and vacuoles. The functions of these parts include providing structural support, controlling what enters and exits the cell, storing nutrients, and carrying out photosynthesis.

• The structure of a plant cell includes a brain, spinal cord, and nerves. The functions of these parts include thinking and sending signals.

• The structure of a plant cell includes a metal frame, wheels, and engine. The functions of these parts include transportation and power generation.

• The structure of a plant cell includes bones, muscles, and blood vessels. The functions of these parts include movement and transportation of oxygen.