Download The Cytoplasm The Cytosol a Viscous watery fluid which all the

The Cytoplasm The Cytosol - Viscous watery fluid which all the sugars, salts and other water soluble elements of the cell are dissolved in - Components: o 75-­‐90% water o Proteins/carbohydrates/lipids o Minerals – sodium/ chloride - Low levels of sodium (15mmol/L) - Low levels of chloride (10mmol/L) - High levels of potassium (150mmol/L) - Ion gradients established by active transport - Ribosomes within cytosol assemble amino acids into proteins The Cytoskeleton (component of cytoplasm) - Filamentous proteins in cytoplasm that give structural support and allow movement - Provides structural reinforcement - Contains: o Intermediate filament (Keratin) o Microtubule (move the cell membrane) o Microfilaments (Muscle contraction) The Cytoplasmic organelles: - Major functional compartments of the cel - Many organelles are separated by the cytosol by a lipid bilayer similar in structure to the plasma membrane - The major organelles include: o Mitochondria Synthesises ATP for the cell ! Surrounded by a double membrane (outer and inner) • Inner membrane has folds called cristae • It is in the inner membrane that the enzymes responsible for the production of ATP is concentrated ! Space between cristae called the matrix ! Contains enzymes involved in transferring energy from nutrients to ATP (Enzymes are essential) ! Acts as power house of cell ! Contains circular DNA and Ribosomes ! Allows you to strip enzymes from molecules and store in ATP o Rough and Smooth Endoplasmic Reticulum ! Membrane-­‐based organelle, which play key roles in the synthesis of many molecules in the cell ! Manufacture materials for the cell Rough ER (RER) • Continuous with nucleus and contains ribosomes (which gives it the rough texture) • Involved in synthesis of proteins and phospholipids Smooth ER (SER) • Lacks ribosomes • Synthesis of lipids, steroid hormones and carbohydrates • Detoxification (liver and kidneys) • Calcium storage (skeletal and cardiac muscle) o Golgi Apparatus ! Modifies proteins from RER; post-­‐
translational modifications ! Sorts and packages proteins; vesicles delivered to other locations (e.g. cell membrane ! Synthesis of carbohydrates ! Comprised of membrane sheets ! Transport reticulum fuse with Golgi and are adapted then sent off ! Transport Vesicles: deliver proteins from the ER to the Golgi apparatus ! Secretory vesicles export the packaged materials to other location Organelle Function Mitochondria Allows you to strip enzymes from molecules and store in ATP Ribosomes Makes proteins Rough endoplasmic Involved in synthesis of proteins and phospholipids reticulum Smooth endoplasmic Synthesis of lipids, steroid hormones and carbohydrates, detoxification and reticulum calcium storage Gogli Apparatus Sorts and packages proteins; vesicles delivered to other locations Cytoskeleton Provides an important structural framework Nucleus Cell function and reproduction Nucleoli Gives rigidity and structure Lysosomes Immune system to kill bacteria Cytoplasmic Inclusions: - Not a feature of all cells - These particles are chemical substances often involved in the specialised function of that particular cell Variable Monitored by condition receptor Cilia Motile (moveable) cellular extension on cell surface - Propel substances (mucous) o Brush mucous and dust out of airways Control centre - Contain microtubules in a 9 + 2 arrangement Sensory data recieved sent - E.g. windpipes are lined with cilia signal Homeostasis - The body has a high capacity to maintain a stable internal environment Commands Returns sent to o Essential to sustain cellular activity (hence life) variable to effector organ - The body has mechanisms to detect change and initiate homeostasis responses necessary to restore internal stability; o Involves virtually all the organ systems - Maintaining homeostasis requires communication between body cells. - Communication mediated via o Nervous system (neural impulses) o Endocrine system (hormone signals) *Important systems