Cell Structure Basics

Cell Structure

• Plasma Membrane: Semi-permeable membrane that separates the cell from its environment.
• Cytoplasm: Jelly-like substance inside the cell where metabolic processes take place.
• Nucleus: Control center of the cell where DNA is stored.
• Mitochondria: Organelles responsible for generating energy for the cell through cellular respiration.
• Endoplasmic Reticulum (ER): Network of membranous tubules and cisternae involved in protein synthesis, lipid synthesis, and detoxification.
• Ribosomes: Small organelles found throughout the cytoplasm, responsible for protein synthesis.
• Lysosomes: Membrane-bound sacs containing digestive enzymes, responsible for breaking down and recycling cellular waste and foreign substances.
• Golgi Apparatus: Complex of flattened sacs and tubules involved in protein modification, sorting, and packaging.

Cell Functions

• Metabolism: Conversion of energy and nutrients into cellular components.
• Growth and Development: Increase in cell size and number, leading to tissue growth and development.
• Response to Stimuli: Ability of cells to respond to changes in their environment.
• Reproduction: Process of cell division, resulting in the creation of new cells.
• Waste Management: Removal of waste products from the cell.

Cell Types

• Prokaryotic Cells: Lack a true nucleus, typically found in bacteria.
• Eukaryotic Cells: Possess a true nucleus, found in plants, animals, fungi, and protists.
• Stem Cells: Undifferentiated cells capable of differentiating into various cell types.

Cell Division

• Mitosis: Process of cell division resulting in two daughter cells with the same number of chromosomes as the parent cell.
• Meiosis: Process of cell division resulting in four daughter cells with half the number of chromosomes as the parent cell, typically occurs in reproductive cells.

Cellular Transport

• Passive Transport: Movement of molecules from an area of high concentration to an area of low concentration, requiring no energy.
  • Diffusion: Random movement of molecules from high to low concentration.
  • Osmosis: Movement of water molecules from high to low concentration.
• Active Transport: Movement of molecules from an area of low concentration to an area of high concentration, requiring energy.

Cell Structure

• The plasma membrane is a semi-permeable membrane that separates the cell from its environment and regulates what enters and leaves the cell.
• Cytoplasm is a jelly-like substance inside the cell where metabolic processes take place, providing a medium for chemical reactions to occur.
• The nucleus is the control center of the cell where DNA is stored, and it plays a critical role in regulating cell growth and division.
• Mitochondria are organelles responsible for generating energy for the cell through cellular respiration, producing ATP from glucose.
• The Endoplasmic Reticulum (ER) is a network of membranous tubules and cisternae involved in protein synthesis, lipid synthesis, and detoxification, serving as a transport system for proteins and lipids.
• Ribosomes are small organelles found throughout the cytoplasm, responsible for protein synthesis, reading messenger RNA (mRNA) to assemble amino acids into proteins.
• Lysosomes are membrane-bound sacs containing digestive enzymes, responsible for breaking down and recycling cellular waste and foreign substances, maintaining cellular homeostasis.
• The Golgi Apparatus is a complex of flattened sacs and tubules involved in protein modification, sorting, and packaging, helping to prepare proteins and lipids for transport out of the cell.

Cell Functions

• Metabolism involves the conversion of energy and nutrients into cellular components, such as carbohydrates, proteins, and fats.
• Cell growth and development occur through an increase in cell size and number, leading to tissue growth and development.
• Cells respond to stimuli through various signaling pathways, allowing them to adapt to changes in their environment.
• Reproduction involves the process of cell division, resulting in the creation of new cells, which is essential for growth, repair, and replacement of cells.
• Waste management involves the removal of waste products from the cell, which is crucial for maintaining cellular homeostasis and preventing the buildup of toxic substances.

Cell Types

• Prokaryotic cells lack a true nucleus, typically found in bacteria, and have a simpler cellular structure and function.
• Eukaryotic cells possess a true nucleus, found in plants, animals, fungi, and protists, and have a more complex cellular structure and function.
• Stem cells are undifferentiated cells capable of differentiating into various cell types, playing a crucial role in development and tissue repair.

Cell Division

• Mitosis is the process of cell division resulting in two daughter cells with the same number of chromosomes as the parent cell, occurring in somatic cells.
• Meiosis is the process of cell division resulting in four daughter cells with half the number of chromosomes as the parent cell, typically occurring in reproductive cells.

Cellular Transport

• Passive transport is the movement of molecules from an area of high concentration to an area of low concentration, requiring no energy, and includes diffusion and osmosis.
• Diffusion is the random movement of molecules from high to low concentration, eventually reaching equilibrium.
• Osmosis is the movement of water molecules from high to low concentration, helping to maintain cellular homeostasis.
• Active transport is the movement of molecules from an area of low concentration to an area of high concentration, requiring energy, and is often used to maintain cellular homeostasis and regulate ion balance.

Test your knowledge of the cell's components and their functions, including the plasma membrane, cytoplasm, nucleus, mitochondria, and endoplasmic reticulum.