Human Cell Structure and Function PDF

Human Cell Structure and Function The Building Blocks of the Body Introduction to the Human Cell A human cell is the fundamental unit of life. Types of cells: somatic cells and germ cells. Cells perform various functions: energy production, growth, reproduction, and commun...

Human Cell Structure and Function The Building Blocks of the Body Introduction to the Human Cell A human cell is the fundamental unit of life. Types of cells: somatic cells and germ cells. Cells perform various functions: energy production, growth, reproduction, and communication. Overview of Cell Components Cells consist of various organelles, each with distinct roles. Key components include the nucleus, mitochondria, cell membrane, endoplasmic reticulum, Golgi apparatus, and lysosomes. Cell Membrane Structure: Phospholipid bilayer with embedded proteins, cholesterol, and Functions: Selectively permeable barrier. carbohydrates. Facilitates communication via receptors and channels. Protects cellular integrity.  Structure: Function: The Nuclear control center, envelope, housing nucleoplasm, genetic nucleolus, and material (DNA). chromatin. Nucleus Regulates cell Nucleolus is activities responsible for through gene ribosome expression. production. Mitochondria Structure: Double membrane, with an inner membrane forming folds (cristae) to increase surface area. Function:Energy production (ATP) through cellular respiration. Plays a role in apoptosis (programmed cell death). Mitochondria have their own DNA, which supports the endosymbiotic theory.  Endoplasmic Reticulum (ER) Types: Rough ER: Studded with ribosomes, involved in protein Structure: A network of synthesis. Function: Transport and membrane-bound tubes Smooth ER: Lacks ribosomes, synthesis of molecules. and sacs. involved in lipid synthesis and detoxification. Golgi Apparatus Structure: Stacks of flattened membrane-bound sacs (cisternae). Function: Modifies, sorts, and packages proteins and lipids for transport to their destinations. Produces lysosomes. Works closely with the ER for the processing and packaging of proteins.  Structure: Membrane-bound vesicles containing hydrolytic enzymes. Function:Break down waste, damaged cell parts, and invading Lysosome pathogens. s Involved in apoptosis (programmed cell death). Role in maintaining cellular health by removing debris.  Structure: Small, non-membrane-bound organelles made of RNA and proteins. Found on Rough ER or free in cytoplasm. Function: Sites of protein synthesis Ribosomes (translation of mRNA into polypeptides). Role in gene expression and cellular function.  Cytoplasm: Cytoskeleton: Cytoplasm and Gel-like fluid where organelles are suspended. A network of protein filaments and tubules (microtubules, Cytoskeleton It allows for the movement of actin filaments, intermediate materials within the cell. filaments) that provide structure and aid in movement.  Vacuoles: Larger in plant cells, but present in human cells for storage of The Role substances. of Vesicles: Small membrane-bound Vacuoles sacs that transport materials within the cell, including to/from the cell and membrane. Vesicles Function: Storage and transport of nutrients, waste, and other materials.  Prophase: Overview of the Chromosomes stages of mitosis: condense, nuclear membrane dissolves. Cell Division - Metaphase: Anaphase: Sister Chromosomes align chromatids separate. in the center. Mitosis Role of mitosis Telophase: Nuclear growth, repair, and membrane reforms, reproduction of somatic cell begins to divide. cells.  Cells communicate through signaling molecules and receptors (e.g., hormones, neurotransmitters). Cellular Functions and Cell signaling regulates processes such as growth, immune response, Communicatio and homeostasis. n Communication through gap junctions, tight junctions, or chemical signals. Conclusion Each part of the cell has a specific function to maintain the viability of the organism Somatic cells reproduce themselves through the process o mitosis Germ cells reproduce through the process of meiosis It is important to understand how the body functions on the cellular level to comprehend the physiology and pathophysiology of the body and its systems.