Results for: 'organic substances'
By: HWC, Views: 84
The bulk of the plant body is comprised of ground tissue. Vascular tissue threads through the ground tissue. It distributes water, solutes, and organic substances through the plant body. Dermal tissue covers and protects the surfaces of the root and shoot systems.
Vascular tissues in a corn stem and a buttercup root
By: HWC, Views: 62
Vascular tissues in a corn stem and a buttercup root. The cells that make up each tissue. Xylem conducts water and dissolved ions. It also helps mechanically support a plant. The cells, called vessel members and tracheids, are dead at maturity. Their lignified walls interconnect and serve as p...
Enzyme structure - Properties of enzymes
By: HWC, Views: 5387
■ Enzymes are proteins that catalyze reactions. ■ Some enzymes have two parts: a protein or apoenzyme and a non-protein or cofactor. ■ Cofactor can be a metal ion or another organic molecule called a coenzyme. ■ Coenzymes often come from vitamins. ■ Cofactors affect the shape of...
By: HWC, Views: 5071
Biological organic compounds contain covalent bonds, mainly C-C and C-H bonds, but also both C and H bonded to such other atoms as O and N. Some of these covalent bonds are nonpolar. Others are polar, either because one atom in the group "hogs" electrons away from other atoms in the group, or...
Endocytosis - pinocytosis, receptor mediated and Transcytosis
By: HWC, Views: 5592
Pinocytosis is the process in which a cell "drinks" a tiny droplet Of extracellular fluid, including its solutes. Pinocytosis (Cell Drinking) is the process by which the cell takes in fluids (as well as any small molecules dissolved in those fluids). • The plasma membrane folds inward to...
Mechanisms of capillary exchange (transcytosis & bulk flow)
By: HWC, Views: 5217
■ This method of capillary exchange is mainly used to transport small amounts of large, lipid-insoluble (water soluble) molecules, such as large proteins. ■ Substances, packaged in vesicles, move through endothelial cells via endocytosis and exocytosis. ■ This method of exchange is th...
Brief Summary on Photosynthesis - Animation
By: HWC, Views: 4595
Can increase its weight by 150 pounds as it grows. Where does the new tissue come from? From the soil? From water? Or possibly from the air? The amazing truth is that new material. comes from an invisible gas in the air. In the process of photosynthesis, plants capture carbon dioxide ga...
Mechanisms of capillary exchange
By: HWC, Views: 5725
■ The primary role of capillaries is to permit the exchange of nutrients and wastes between the blood and tissue cells (via interstitial fluid). ■ Oxygen and nutrients move from the blood to the cells. ■ Carbon dioxide and other wastes move from the cells to the blood. The three ba...
Types of antimicrobial substances (interferons & complement protein)
By: HWC, Views: 5735
• Found in blood and interstitial fluids. • Discourage microbial growth. • Include interferon and complement proteins. • Produced and released by virus-infected lymphocytes. • Enter new cells and inhibit viral replication. • Act against a large variety of viruses (non-speci...