General Biology: Transport Mechanisms and Carbohydrates

GENERAL BIOLOGY TRANSPORT MECHANISM - Carbohydrates act like **\"ID tags,\"** allowing cells to **recognize and communicate with each other.** - Help **cells stick to each other, forming tissues.** - Provides a **protective barrier against physical and chemical damage** - Lipid...

GENERAL BIOLOGY TRANSPORT MECHANISM - Carbohydrates act like **\"ID tags,\"** allowing cells to **recognize and communicate with each other.** - Help **cells stick to each other, forming tissues.** - Provides a **protective barrier against physical and chemical damage** - Lipid form a flexible, **protective Layer** - Proteins **help nutrients and waste pass in and out of the cell** - ***Hydrophilic* (water -loving)** phospholipid Heads - ***Hydrophobic*** **(water-fearing)** phospholipid tails. WHAT IS TRANSPORT MECHANISM? - Refers to the **ways substances move in and out of cells** through the cell membrane. What are the materials that are being transported by the cell membrane? WHAT ARE THE FACTORS THAT CAN AFFECT MEMBRANE TRANSPORT? ***Size of the Molecule:*** - Smaller molecules (like water or oxygen) can pass through the membrane more easily, while larger molecules (like proteins) may need special help to get across. ***Concentration Gradient:*** - If there\'s a big difference in the concentration of a substance, it will move faster from an area of high concentration to an area of low concentration. ***Temperature:*** - Higher temperatures make molecules move faster, which can speed up membrane transport. Colder temperatures slow things down. ***Membrane Permeability:*** - Some membranes are more selective, allowing only certain molecules to pass through easily. TYPES OF TRANSPORT MECHANISM ***[PASSIVE]*** ***[ACTIVE]*** ----------------------------- ---------------------------- **DIFFUSION** **PRIMARY ACTIVE** **OSMOSIS** **SECONDARY ACTIVE** **FACILITATED** **BULK TRANSPORT** **PASSIVE TRANSPORT** - **Does not require the use of energy** **(ATP)** driving force is usually kinetic energy in the form of a **concentration gradient (high conc. Low conc.)** **DIFFUSION** - Where particles move from an area where there is a lot of them **(high concentration)** to an area where there are fewer of them **(low concentration)** from high to low concentration. ***(MANY TO FEW)*** **OSMOSIS** - When water moves through a partially permeable membrane from **high to low concentration.** **FACILITATED** - Where molecules move across the cell membrane **with the help of special proteins called transport proteins or carrier proteins.** **Active Transport** - **Requires the use of energy (ATP**) molecules move against the concentration gradient **(low conc. → high conc.)** **PRIMARY ACTIVE TRANSPORT** - Involves moving molecules across a cell membrane **from an area of low concentration to an area of high concentration.** **SECONDARY ACTIVE TRANSPORT** - Moves molecules **against their concentration gradient, but it relies on the energy** created by primary active transport. **Bulk Transport (Vesicular Transport)** - Transporting **large quantities of substances,** or large molecules, across the cell membrane. CARBOHYDRATES "THE BODY\'S ENERGY SOURCE" **WHAT ARE MACROMOLECULES?** - Macromolecules are **large, complex molecules essential for life, made up of smaller units called monomers.** The four major types of macromolecules are: 1. Carbohydrates 2. Proteins 3. Lipids 4. Nucleic Acids **WHAT ARE CARBOHYDRATES?** - Are comprised of the elements: ***carbon, hydrogen, and oxygen*** - Stoichiometric formula of carbohydrates is: **(CH 2o)n** - The primary energy source of the human body. STRUCTURE OF CARBOHYDRATES - Carbohydrates are collectively called as **saccharides** (Greek**: sakcharon = sugar).** Carbohydrates can be as: - **Monosaccharide** - 1 saccharide (one sugar) - **Disaccharide** -- 2 saccharide (two sugar) - **Polysaccharide** -- many saccharide (3 sugar) MONOSACCHARIDE Glucose Used in dextrose, blood sugar; ----------- --------------------------------- Galactose Found in milk and milk products Fructose Found in fruits and honey DISACCHARIDE maltose Glucose + glucose found in malt --------- --------------------- --------------------------------------------------------- sucrose Glucose + fructose found in regular table sugar, sugarcane, and sugar beet lactose Glucose + galactose found in milk and milk products POLYSACCHARIDE Starch/Amylose storage form of glucose in **plants** ---------------- --------------------------------------------------------------------- Amylopectin storage form of glucose in **plants** Glycogen storage form of glucose **animal; stored in the liver and muscles** Cellulose structural material in **plants\--cell wall** **FUNCTION OF CARBOHYDRATES:** **ENERGY PRODUCTION:** Carbs are broken down into glucose, which powers cells. **ENERGY STORAGE:** Excess glucose is stored as glycogen in muscles and the liver. **STRUCTURAL ROLE:** Some carbohydrates, like cellulose and chitin, provide structure. IMPORTANCE OF CARBOHYDRATES FOR HUMANS ***Carbohydrates are vital for:*** - **Fueling the Brain and Muscles** during exercise and daily activities. - **Supporting Digestion** - fiber helps prevent constipation. - **Preventing Protein Breakdown** -carbs spare proteins from being used for energy. **MISCONCEPTIONS: CARBS LEADING TO WEIGHT GAIN** **WHERE DO WE GET CARBS?** - **Simple Carbs**: Sugars found in candy, soda, fruits. - **Complex Carbs**: Found in bread, rice, pasta, and vegetables. - **Fiber:** A complex carb that supports digestion (found in whole grains, fruits, and vegetables).