Cell Transport and Homeostasis Review

What is homeostasis?

• The process of cell division

• The constant internal physical and chemical conditions maintained by organisms

• The breakdown of glucose

• The movement of water across a membrane

Answer explanation

Homeostasis refers to the constant internal physical and chemical conditions maintained by organisms, ensuring stability despite external changes. This is crucial for survival and proper functioning.

Tags

NGSS.HS-LS1-3

What is the role of the cell membrane in cellular transport?

• It produces energy for the cell

• It controls what enters and leaves the cell

• It stores genetic information

• It synthesizes proteins

Answer explanation

The cell membrane plays a crucial role in cellular transport by controlling what enters and leaves the cell, maintaining homeostasis and allowing selective permeability.

Which type of transport does not require energy?

• Active transport

• Passive transport

• Endocytosis

• Exocytosis

Answer explanation

Passive transport does not require energy as it relies on the natural movement of molecules from areas of high concentration to low concentration. In contrast, active transport, endocytosis, and exocytosis require energy.

What is facilitated diffusion?

• Diffusion of water across a membrane

• Diffusion that requires energy

• Diffusion involving proteins that span the cell membrane

• Diffusion of large particles through endocytosis

Answer explanation

Facilitated diffusion is a process where molecules pass through the cell membrane via specific proteins that span the membrane, allowing substances to move down their concentration gradient without the use of energy.

What happens to a cell in a hypertonic solution?

• It swells

• It shrinks

• It remains the same

• It bursts

Answer explanation

In a hypertonic solution, the concentration of solutes outside the cell is higher than inside. Water moves out of the cell to balance the solute concentrations, causing the cell to shrink.

What is active transport?

• Movement of substances without energy

• Movement of substances using energy

• Movement of substances through diffusion

• Movement of substances through osmosis

Answer explanation

Active transport is the movement of substances across cell membranes using energy, typically in the form of ATP. This process allows cells to move substances against their concentration gradient, unlike passive transport methods.

Which ions are pumped into the cell during active transport?

• Sodium ions (Na+)

• Calcium ions (Ca2+)

• Potassium ions (K+)

• Chloride ions (Cl-)

Answer explanation

During active transport, potassium ions (K+) are pumped into the cell, which is crucial for maintaining the cell's membrane potential and overall function. This process is primarily facilitated by the sodium-potassium pump.

What process involves the cell membrane wrapping around a particle to bring it into the cell?

• Exocytosis

• Osmosis

• Endocytosis

• Diffusion

Answer explanation

Endocytosis is the process where the cell membrane engulfs a particle, forming a vesicle to bring it into the cell. This distinguishes it from exocytosis, which is the process of expelling materials from the cell.

What is the role of exocytosis in a cell?

• Bringing particles into the cell

• Moving waste and other materials outside the cell

• Transporting ions into the cell

• Facilitating diffusion

Answer explanation

Exocytosis is the process by which cells move waste and other materials outside. This is crucial for maintaining cellular function and homeostasis, making 'Moving waste and other materials outside the cell' the correct choice.

Which of the following will occur if a cell is in a hypotonic solution?

• Water will move out of the cell through active transport to maintain homeostasis.

• Water will move into the cell through active transport to maintain homeostasis.

• Water will move out of the cell through passive transport to maintain homeostasis.

• Water will move into the cell through passive transport to maintain homeostasis.

Answer explanation

In a hypotonic solution, water moves into the cell through passive transport due to osmosis, as the concentration of solutes is lower outside the cell. This influx helps maintain homeostasis by balancing internal and external solute levels.

Tags

NGSS.HS-LS1-3