Cell Parts And Membrane Transport Quiz

The cell membrane is made up of a phospholipid bilayer. Phospholipids have a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail. These phospholipids arrange themselves in a double layer, with the hydrophilic heads facing outward towards the watery environment both inside and outside the cell, and the hydrophobic tails facing inward, creating a barrier that separates the cell from its surroundings. This structure allows the cell membrane to selectively control the movement of substances in and out of the cell.

Active transport and passive transport are two different mechanisms by which substances are transported across cell membranes. Passive transport does not require energy and occurs through diffusion or facilitated diffusion, where substances move from an area of high concentration to an area of low concentration. On the other hand, active transport requires energy to move substances against their concentration gradient, from an area of low concentration to an area of high concentration. Therefore, the correct answer is energy, as active transport relies on the expenditure of energy to transport substances across the cell membrane.

The Golgi apparatus is responsible for processing, packaging, and "shipping" molecules in a eukaryotic cell. It receives molecules from the endoplasmic reticulum, modifies them, and then packages them into vesicles for transport to their final destination within or outside the cell. The Golgi apparatus plays a crucial role in the secretion of proteins, lipids, and other molecules, as well as in the formation of lysosomes. It consists of a series of flattened sacs called cisternae, which are stacked on top of each other.

Diffusion is the movement of molecules from an area of high concentration to an area of low concentration. This process occurs due to the random motion of molecules and aims to achieve a state of equilibrium where the concentration is equal throughout the system. Therefore, the correct answer is "an area of high concentration to an area of low concentration."

Animal cells do not have a cell wall. Unlike plant cells, animal cells are surrounded by a flexible cell membrane that allows for movement and interaction with their environment. The absence of a cell wall in animal cells enables them to change shape, which is essential for functions such as cell division and the ability to engulf particles. The cell membrane also regulates the movement of substances in and out of the cell, maintaining homeostasis.

When an animal cell is surrounded by fresh water, the concentration of solutes inside the cell is higher than outside. This creates a concentration gradient, causing water to move into the cell through osmosis. As water moves into the cell, the cell starts to swell and can eventually burst if the influx of water is not regulated. Therefore, the osmotic pressure causes water to move into the cell.

Prokaryotic cells lack a nucleus. Unlike eukaryotic cells, which have a distinct membrane-bound nucleus that contains the genetic material, prokaryotic cells have their genetic material dispersed in the cytoplasm. The absence of a nucleus allows for a simpler and more efficient structure in prokaryotic cells, which are typically smaller and have a simpler organization compared to eukaryotic cells. This lack of a nucleus also means that prokaryotic cells do not have a nuclear membrane or a distinct nucleolus.

Ribosomes are the cell structures that assemble proteins using coded instructions from the nucleus. They are responsible for protein synthesis, which is the process of building proteins from amino acids. Ribosomes can be found in both prokaryotic and eukaryotic cells, and they can be free-floating in the cytoplasm or attached to the endoplasmic reticulum. The coded instructions for protein synthesis are stored in the form of DNA in the nucleus, and they are transcribed into messenger RNA (mRNA) molecules. These mRNA molecules then travel to the ribosomes, where the actual process of protein synthesis takes place.

Fungi cells are similar to plant cells in that they both have a cell wall, which provides structural support and protection. However, plant cells have chloroplasts, which are specialized organelles responsible for photosynthesis, while fungi cells do not possess chloroplasts. Chloroplasts contain chlorophyll, the pigment that captures sunlight and converts it into energy for the plant. Since fungi are heterotrophic organisms that obtain nutrients by absorbing organic matter from their environment, they do not require chloroplasts for energy production. Therefore, the correct answer is chloroplasts.

Based on the information given, it can be inferred that the cell in the picture would swell. This can be deduced because the opposite of shrinking is swelling, and the other options (isotonic and beast) do not make sense in this context.