Physiology Part II

•Cells

•DNA Deoxyribonucleic acid

•RNA Ribonucleic acid

•Proteins

•ATP (Adenosine Triphosphate)

•Photosynthesis

•Hearing

•Kidneys

•Pancreas

•Liver

•Gallbladder

•Digestive System

DNA-RNA Animation

Cells•Cell The cell is the structural and functional unit of all living organisms. Humans have an estimated 100 trillion or 1014 cells

Deoxyribonucleic acid, or DNA is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all living organisms.

•The main role of DNA is the long-term storage of information and it is often compared to a set of blueprints, since DNA contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information.

•Ribonucleic acid (RNA) is a nucleic acid polymer consisting of nucleotide monomers that plays several important roles in the processes that translate genetic information from deoxyribonucleic acid (DNA) into protein products; RNA acts as a messenger between DNA and the protein synthesis complexes known as ribosomes,

•Proteins Many proteins are enzymes that catalyze biochemical reactions, and are vital to metabolism. Other proteins have structural or mechanical functions, such as the proteins in the cytoskeleton, which forms a system of scaffolding that maintains cell shape. Proteins are also important in cell signaling, immune responses.

ATP (Adenosine Triphosphate)

For your muscles -- in fact, for every cell in your body -- the source of energy that keeps everything going is called ATP. ATP is the biochemical way to store and use energy.

Adenosine 5'-triphosphate (ATP) is a multifunctional nucleotide that is most important as a "molecular currency" of intracellular energy transfer. In this role ATP transports chemical energy within cells for metabolism.

•It is produced as an energy source during the processes of photosynthesis and cellular respiration and consumed by many enzymes and a multitude of cellular processes including biosynthetic reactions, motility and cell division.

•ATP consists of adenosine - itself composed of an adenine ring and a ribose sugar - and three phosphate groups (triphosphate).

Photosythesis

•Process by which green plants and certain other organisms transform light into chemical energy.In green plants, light energy is captured by chlorophyll in the chloroplasts of the leaves and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds (simple and complex sugars) that are the basis of both plant and animal life.•During the light-dependent stage (light reaction), chlorophyll absorbs light energy, which excites some electrons in the pigment molecules to higher energy levels; these leave the chlorophyll and pass along a series of molecules, generating formation of NADPH (an enzyme) and high-energy ATP molecules.

Photosynthesis Animation

6CO2 + 12H2O + Light –> C6H12O6 + 6O2+ 6H2O

Sugar

•The NADPH oxidase (nicotinamide adenine dinucleotide phosphate-oxidase) complex is an enzyme complex.

•It generates superoxide by transferring electrons from NADPH inside the cell across the membrane and coupling these to molecular oxygen to produce the superoxide, which is highly reactive free radical

Hearing•The ear has three major regions: the outer ear, the middle ear and the inner ear.

•The process of hearing begins when sound waves make it to the middle ear, causing the ear drum to vibrate.

•The human ear is the anatomical structure responsible for hearing and balance. •The second part of the outer ear, the external auditory canal, is a passageway in the temporal lobe of the skull, which leads from the outside of the head and extends inward and slightly upwards. In the adult human, it is lined with skin and hairs and is approximately 1 in (2.5 cm) long.

•The third part of the outer ear, the tympanic membrane or eardrum, is a thin, concave membrane stretched across the inner end of the external auditory canal much like the skin covering the top of a drum. The eardrum transmits sound to the middle ear by vibrating in response to sounds traveling down the external auditory canal.

Hearing Animation

•Your kidneys are two bean-shaped organs, each about the size of your fist. They are located in the middle of your back, just below your rib cage, on either side of your spine. Your kidneys weigh about 0.5 percent of your total body weight.

• Although the kidneys are small organs by weight, they receive a huge amount -- 20 percent -- of the blood pumped by the heart. The large blood supply to your kidneys enables them to do the following tasks:•

•Regulate the composition of your blood•keep the concentrations of various ions and other important substances constant •keep the volume of water in your body constant •remove wastes from your body (urea, ammonia, drugs, toxic substances) keep the acid/base concentration of your blood constant

•Help regulate your blood pressure •Stimulate the making of red blood cells •Maintain your body's calcium levels

Kidneys

Kidney animation detailed

Kidney Stone Animation

Pancreas/Diabetes

•Type 2 diabetes means that your body doesn't make enough insulin, or doesn't properly use the insulin your body makes. Insulin, which is made in your pancreas.

•helps your body's cells use sugar from your bloodstream, which comes from foods and drinks. Sugar is a source of energy for cells.

Type 1 diabetes. This form often affects children, but adults can develop it, too. In this form of diabetes, the body can't make insulin. The immune system by mistake attacks the cells in the pancreas that make and release insulin. As these cells die, blood sugar levels rise. People with type 1 diabetes need insulin shots.Type 2 diabetes. This Web site focuses on type 2 diabetes, which is rising fast in the US. It accounts for most diabetes cases. Typically, with type 2 diabetes, the body still makes insulin, but its cells can't use it. This is called insulin resistance. Over time, high levels of sugar build up in the bloodstream. Being overweight and inactive increase the chances of developing type 2 diabetes. Diabetes animation

•The Pancreas is located behind the liver and stomach. In addition to secreting digestive enzymes, the pancreas secretes the hormones insulin and glucagon into the bloodstream. The release of insulin into the blood lowers the level of blood glucose (simple sugars from food) by enhancing glucose to enter the body cells, where it is metabolized. If blood glucose levels get too low, the pancreas secretes glucagon to stimulate the release of glucose from the liver. The pancreas secretes insulin

in response to glucose levels in the blood

Liver

•The liver is in the right upper abdomen. The liver serves many functions, including the detoxification of substances delivered from the intestines, and the synthesis of many proteins.

•the largest gland in the body, a spongy mass of wedge-shaped lobes that has many metabolic and secretory functions. The liver secretes bile, a digestive fluid; metabolizes proteins, carbohydrates, and fats; stores glycogen, vitamins, and other substances; synthesizes blood-clotting factors; removes wastes and toxic matter from the blood

•A liver transplant may be recommended for: liver damage due to:

• alcoholism (Alcoholic cirrhosis )• end-stage liver disease (primary biliary cirrhosis) •long-term (chronic) active infection (hepatitis) •liver (hepatic) vein clot (thrombosis) •birth defects of the liver or bile ducts (biliary atresia) •metabolic disorders associated with liver failure (e.g., Wilson's disease)

Arteries / Veins/ Capillaries inside Liver

Liver (cont)

Liver animation

The gallbladder is a muscular sac located under the liver. It stores and concentrates the bile produced in the liver that is not immediately needed for digestion. Bile is released from the gallbladder into the small intestine

Gallbladder

The Digestive System

•Digestion is the process by which the body converts food into basic substances that can either be absorbed in the bloodstream as nutrients or passed out of the body as waste.

•This process of breakdown and assimilation occurs within the digestive tract, a convoluted tube more than 30 feet long that is lined with a mucous membrane.

•Other digestive juices required by the small intestine to digest and absorb food, particularly fats and starches, come from the pancreas, an organ located just behind the stomach.

•Whatever substances are not assimilated into the bloodstream through the small intestine move into the large intestine. Within the large intestine, waste material is processed into stool (feces), and water and certain chemicals are absorbed into the bloodstream to preserve the body's fluid balance.

Digestive System Animation

The tract includes several hollow organs

•The mouth

•Esophagus

•Stomach

•Small intestine

•Large intestine

•each of which has a specific function in digestion. The muscles of these organs move the food through the system, while mucus lubricates the tract and prevents irritation. The liver and pancreas are also critical organs in digestion. While not an essential organ, the gallbladder is involved in digestion as well.

The Digestive System (cont)