Células (Cells)

Teoria Celular (Cell Theory)

The cell theory is a fundamental concept in biology that describes the properties of cells, the basic unit of life. It consists of three main principles:

• All living beings are formed by cells.

• Cells are the smallest morphological and functional units of life.

• All cells arise from pre-existing cells.

Exception: Viruses are considered acellular because they lack cellular structure and only exhibit life processes inside host cells.

Partes Básicas da Célula (Basic Parts of the Cell)

All cells share certain fundamental structures:

• Membrana plasmática (Plasma membrane): The outer boundary that controls the movement of substances in and out of the cell.

• Citoplasma (Cytoplasm): The jelly-like substance inside the cell where organelles are suspended.

• Material genético (Genetic material): DNA or RNA that carries genetic information.

Tipos de Células (Types of Cells)

• Procarionte (Prokaryotic): Cells without a defined nucleus; genetic material is free in the cytoplasm. Example: Bacteria.

• Eucarionte (Eukaryotic): Cells with a true nucleus, where genetic material is enclosed by a nuclear membrane. Examples: Plant and animal cells.

Organelas Celulares (Cell Organelles)

Organelles are specialized structures within cells that perform distinct processes:

• Mitocôndria (Mitochondria): Site of cellular respiration and energy production.

• Ribossomo (Ribosome): Responsible for protein synthesis.

• Retículo endoplasmático (Endoplasmic reticulum): Involved in protein and lipid synthesis.

• Complexo golgiense (Golgi apparatus): Modifies, sorts, and packages proteins and lipids for storage or transport.

• Lisosomo (Lysosome): Contains digestive enzymes to break down waste.

• Centríolo (Centriole): Involved in cell division in animal cells.

• Vacuolo (Vacuole): Stores nutrients, waste products, and helps maintain cell shape (large in plant cells).

Diferenças entre Célula Vegetal e Célula Animal (Differences Between Plant and Animal Cells)

• Célula Vegetal (Plant Cell): Has a cell wall, chloroplasts for photosynthesis, and a large central vacuole.

• Célula Animal (Animal Cell): Lacks a cell wall and chloroplasts, but contains centrioles.

Additional info: The image provides a visual summary of cell theory, basic cell parts, types of cells, and main organelles, with clear distinctions between plant and animal cells. It also highlights viruses as an exception to the cell theory.