Cell Structure and Function Online Quiz

In biological terms, tissue is a group of similar cells working together to perform a specific function. While household tissues are made of paper, biological tissue is composed of cells. Organs are made of tissues, not the other way around.

The biological levels of organization start with the simplest unit, the cell. Multiple cells of the same type form tissues, which combine to make organs. Organs work together in organ systems, which ultimately make up a complete multicellular organism.

Plant cells have a rigid outer layer called a cell wall, which provides structure and support, whereas animal cells lack a cell wall. Additionally, plant cells typically have a single large central vacuole, while animal cells have smaller, temporary vacuoles.

The vacuole acts as a storage organelle within the cell, holding water, nutrients, and waste products. In plant cells, a large central vacuole also helps maintain turgor pressure to keep the plant upright.

Mitochondria are known as the powerhouses of the cell because they perform cellular respiration. This process converts nutrients, like glucose, into usable chemical energy in the form of ATP.

Chloroplasts contain chlorophyll, a green pigment that absorbs sunlight to drive photosynthesis. This process allows plants to synthesize glucose from carbon dioxide and water, producing their own food.

Cytoplasm is the jelly-like fluid that fills the inside of a cell and surrounds the organelles. It provides a medium for chemical reactions to occur and helps keep organelles suspended and in place.

The nucleus is often referred to as the brain or control center of the cell because it houses the genetic material (DNA). It coordinates major cell activities, including growth, metabolism, and reproduction.

Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. They are made of protein and a single molecule of DNA, which carries the genomic information from cell to cell.

The cell wall is a rigid outer layer found in plant cells, fungi, and some bacteria. Its primary function is to provide structural support, shape, and protection to the cell.

The cell membrane is a semi-permeable barrier that surrounds the cell. It regulates the entry and exit of substances, ensuring that the cell maintains a stable internal environment.