A Biology Questions On Cell Transport

Active transport is a process in which a cell uses energy to move molecules or ions against their concentration gradient, from an area of lower concentration to an area of higher concentration. This process requires the cell to expend energy in the form of ATP (adenosine triphosphate), which is the main energy currency of cells. Therefore, the statement that active transport requires a cell to expend energy in the chemical form of ATP is true.

The two types of cell transport are active and passive. Active transport refers to the movement of molecules or ions across a cell membrane against their concentration gradient, requiring the use of energy. Passive transport, on the other hand, does not require energy and includes processes like diffusion, where molecules move from an area of high concentration to an area of low concentration. The options "diffusion" and "automobile" are not types of cell transport and are therefore incorrect.

Carrier proteins are a type of transport protein that facilitate the movement of specific substances across a membrane. They bind to the substance being transported and undergo a conformational change to transport it across the membrane. This process is known as facilitated diffusion. Therefore, the statement that carrier proteins are used to transport specific substances across a membrane is true.

Active transport is the correct answer because it requires the use of ATP, which is energy, to move molecules or ions against their concentration gradient. In passive transport, on the other hand, molecules or ions move across the cell membrane without the need for energy. Therefore, since ATP is involved in this cell transport, it is classified as active transport.

Passive transport is a type of cellular transport that does not require energy or the use of ATP (adenosine triphosphate). Unlike active transport, which uses energy to move molecules against their concentration gradient, passive transport relies on the natural movement of molecules from an area of high concentration to an area of low concentration. This can occur through processes such as diffusion, osmosis, and facilitated diffusion. Therefore, energy and ATP are not needed for passive transport to occur.

The statement in the question is incorrect. A hypotonic solution has a lower solute concentration compared to another solution. In a hypotonic solution, water molecules move into the cells, causing them to swell or burst. Therefore, the concentration of both solutions is not equal in a hypotonic solution.

Osmosis is a process in which water molecules move from an area of lower solute concentration to an area of higher solute concentration through a semipermeable membrane. This movement is driven by the concentration gradient and does not require energy. Therefore, the statement that osmosis is the diffusion of water molecules through a cellular membrane is correct.

Passive transport refers to the movement of molecules across a cell membrane without the need for energy or ATP. This process occurs along the concentration gradient, from an area of high concentration to an area of low concentration. Examples of passive transport include diffusion, osmosis, and facilitated diffusion. In contrast, active transport requires energy to move molecules against the concentration gradient. Therefore, the given correct answer, "Passive," accurately describes a type of transport that does not require energy or ATP from the cell to operate.

When the concentration of molecules is equal throughout a cell, it is called equilibrium. In this state, there is no net movement of molecules as the concentration gradient is balanced. This means that the molecules are evenly distributed and there is no overall movement from one area to another. Equilibrium is a dynamic state where molecules continue to move but there is no overall change in concentration.

A hypertonic solution has a higher concentration of solutes compared to the inside of the cell. When a cell is placed in a hypertonic solution, water molecules move out of the cell through osmosis, causing the cell to shrink. This is because water molecules move from an area of lower solute concentration (inside the cell) to an area of higher solute concentration (the hypertonic solution) in order to equalize the concentration on both sides of the cell membrane. Therefore, the statement "Hypertonic solution causes a cell to shrink because of osmosis" is true.

In a hypotonic environment, water diffuses into the cells, causing them to swell and eventually burst. This is because the concentration of solutes outside the cells is lower than inside the cells, creating a concentration gradient that drives water into the cells. As a result, the cells become engorged with water and eventually burst, a process known as cytolysis.

Passive transport is a process in which molecules or ions move across a cell membrane without the use of energy. Osmosis is the passive transport of water molecules across a selectively permeable membrane, from an area of lower solute concentration to an area of higher solute concentration. Diffusion is the passive transport of molecules or ions from an area of higher concentration to an area of lower concentration. Therefore, osmosis and diffusion are the two main types of passive transport. Pumps and endocytosis are not examples of passive transport as they require energy.

Diffusion is the movement of particles from an area of high concentration to an area of low concentration. This is because particles naturally tend to spread out and move towards areas where there are fewer particles. Therefore, the correct answer is "High - to low".

In a hypertonic environment, the concentration of solutes outside the cells is higher than inside the cells. As a result, water moves out of the cells through osmosis, causing the cells to shrink away from the cell walls. This loss of water also leads to a decrease in turgor pressure within the cells.

Active transport refers to the movement of solutes across a cell membrane against their concentration gradient, requiring the use of energy. The sodium-potassium pump is a prime example of active transport, as it actively transports sodium ions out of the cell and potassium ions into the cell, utilizing ATP to drive the process. This process helps maintain the concentration gradients of these ions, which is crucial for various cellular functions such as nerve impulse transmission and muscle contraction.

The given picture is not of endocytosis.

A hypertonic solution causes a cell to shrink because of osmosis. In a hypertonic solution, the concentration of solutes outside the cell is higher than inside the cell. This creates a concentration gradient, causing water to move out of the cell through osmosis, resulting in the cell shrinking.

The correct answer is Endocytosis. Endocytosis is a type of active transport where cells take in substances by engulfing them with their cell membrane. This process allows the cell to bring in large molecules or particles that cannot pass through the membrane on their own. In the image, it is likely that the cell is engulfing a substance, indicating the process of endocytosis.

Facilitated diffusion is a type of passive transport that involves the use of carrier proteins to facilitate the movement of molecules across a cell membrane. Unlike simple diffusion, which occurs directly through the phospholipid bilayer, facilitated diffusion allows for the transport of larger or charged molecules that cannot easily pass through the membrane on their own. The carrier proteins bind to specific molecules and undergo a conformational change to transport them across the membrane. This process does not require energy expenditure by the cell and occurs down the concentration gradient.

Contractile vacuoles are organelles found in certain organisms, such as protists, that live in freshwater environments. These vacuoles function to regulate the water balance within the cell by pumping excess water out of the cell. This helps maintain the cell's internal environment and prevents it from bursting or becoming too diluted. Therefore, contractile vacuoles are used by organisms to pump water out of the cell.

Diffusion is the process by which particles move from an area of higher concentration to an area of lower concentration. It occurs due to the random movement of particles and does not require any external energy input. This movement down the concentration gradient allows for the equalization of particle distribution, resulting in a more uniform concentration throughout the system.

Exocytosis is the process by which a substance is transported out of a cell through the fusion of a vesicle with the cell membrane. This allows the contents of the vesicle to be released into the extracellular space. It is a vital cellular mechanism for the secretion of various substances such as hormones, neurotransmitters, and digestive enzymes. During exocytosis, the vesicle membrane merges with the cell membrane, creating a pore through which the substance is expelled from the cell. This process is essential for cellular communication, signaling, and maintaining homeostasis.

Endocytosis is the process by which substances are taken into a cell from the outside environment. During endocytosis, the cell membrane surrounds and engulfs the substance, forming a vesicle that is then brought into the cell's cytoplasm. This process is important for the uptake of nutrients, the removal of waste materials, and the regulation of cell signaling.

Cells use active transport to move things in and out of the cell through pumps/channels, endocytosis, and exocytosis. Pumps and channels are proteins that actively transport molecules across the cell membrane, requiring energy. Endocytosis is the process by which cells engulf substances from the external environment by forming vesicles. Exocytosis, on the other hand, involves the release of substances from the cell by fusing vesicles with the cell membrane. Diffusion, mentioned in the question, is a passive transport process and not an example of active transport.

Active transport is the process by which substances are moved against their concentration gradient, from an area of low concentration to an area of high concentration. This process requires energy in the form of ATP (adenosine triphosphate) and is carried out by specific proteins in the cell membrane called pumps. These pumps actively transport ions or molecules across the membrane, allowing the cell to maintain a concentration gradient that is necessary for various cellular functions.