Behavior in Bees

Worker bees must communicate with one another about the location of food sources, which may change as a flowers blooms or dies. One way bees do this is by performing a dance. When a worker returns to the hive, it is suddenly surrounded by other worker bees, which sense its movements. There is a round dance that seems to communicate simply that there is food nearby. If the food is farther from the hive, a worker will appear to communicate both the direction and distance of the food through a waggle type dance. Because it is often dark inside the hive, other bees follow the dancing bee's movements mainly through sound, taste, and touch.

Behavior

Most of the time behavior is thought to be the visible result of an animal’s muscular activity, like when a predator chases its prey. However only some behaviors have muscular activity involved but it is less obvious. As when a toad uses muscles to force air from its lungs and shape the sounds in its throat, producing a noise. Nonmuscular activities are also considered behaviors. Another example occurs when an animal secretes a hormone that attracts a mate of the opposite sex. Learning can be considered a behavioral process. A popular example is scientist Pavlov found that if he rang a bell every time he put the meat powder in the dog's mouth, the dog eventually salivated upon hearing the bell alone. Behavior is simply everything an animal does and how it does it.

Spinal Nerves (sensory and motor )

There are 31 pairs of spinal nerves and each has a dorsal root and a ventral root. The dorsal root is sensory (all neurons conduct impulses into the spinal cord) while the ventral root is motor ( all neurons conduct impulses out of the spinal cord). The dorsal root has a ganglion that contains the cell bodies of the sensory neurons that pass through the dorsal root. Each spinal nerve includes numerous sensory, or afferent, and motor, or efferent, neurons. Some of these neurons are classified as somatic, and this conduct impulses to or form the "somatic" structures ( skin, skeletal muscles, tendons, and joints). Other neurons are "visceral", and these conduct impulses to or from the visceral structures (smooth muscle, cardiac muscle, and glands). Therefore, all neurons in spinal nerves and the peripheral nervous system are placed in one of the four categories somatic afferent, somatic efferent, visceral afferent, visceral efferent. Somatic affernt neurons are sensory neurons that conduct impules initiated in receptors in the skin, skeletal muscles, tendons, and joints. Receptors in the skin are responsible for sensing things such as touch, temperature, pressure and pain called exteroceptors. Receptors in skeletal muscles, tendons, and joints, provide info about body position and movement and are called propioceptors.They are unipolar. Somatic efferent neurons are motor neurons that conduct impulses from the spinal cord to skeletal muscles. These neurons are multipolar. Visceral afferent are sensory neurons that conduct impulses initiated in the receptors in the smooth and cardiac muscle. They are reffered to as enteroceptors or visceroceptors. They are unipolar. Visceral efferent are motor neurons that conduct impulses to smooth muscle, cardiac muscle, and glands. They make up the autonomic nervous system. Some begin in the brain and some in the spinal cord. It always takes two visceral efferent neurons to conduct an impulse from the spinal cord or brian in some cases to a muscle or gland.

Stress Depletes Neurotransmitters

When dealing with daily stress the brain uses feel good transmitters called endorphins. When large amounts of endorphins are needed to handle stress, the ratio of many of the other transmitters, one to another, becomes upset causing a chemical imbalance. When we start to feel stress like a sense of urgency and anxiety more stress is caused as a result. Harmful chemicals are released in our bodies that do damage, causing even more stress. This is called the "stress cycle". Emotional fatigue can be a result, and be experienced and felt as depression. The body responds to emotional stess exactly as it responds to physical danger. We are usually unaware of this not felling at all as our bodies are constantly reacting to different emotions. Responding to this mental and emotional struggles with a "fight or flight" response. Which is designed to prepare our bodies for immediate danger. We really don't fight or flee, instead the high energy chemicals produced in many everyday situations boil inside of us, potentially taking years off our lives. Almost all body functions and organs react to stress. The body responds to stress with a series of physiological changes that include increased secretion of adrenaline, elevation of blood pressyrem accerleration of the heartbeat, and greater tension in the muscles, etc. Stress creates an excellent breeding ground for illness. Increased adrenaline production causes the body to step up its metabolism of proteins, fats, and carbs to quickly produce energy for the body to use. the pituitary gland stimulates the release of hormones cortisone and cortisol. These two hormones have the effect of inhibiting the functioning of disease fighting white blood cells and suppressing the immune response. This complex of physical changes known as the "fight or flight" response is also the reason that stress can lead to nutrional deficiencies. Researchers estimate that stress contributes to as many as 8O % og all major illnesses that include cardiovascular disease, cancer, endocrine and metabolic diseases, skin disorders, and all kinds of infections. Studies by the American Medical Association have shown stress to be a factor in over 75% of all illnesses today. Research linking stress to a variety of diseases and illnesses had been the subject of more than 20,000 scientific studies...interesting huh? So let's all try to cool down and not get so stress about Ap bio anymore... we don't want to get sick lol =]

Types of Sensory Receptors

Sensory receptors are organized into five groups; mechanoreceptors, chemoreceptors, electromagnetic receptors, thermoreceptors, and pain receptors. Mechanoreceptors are receptors stimulated by physical stimuli. They respond to mechanical energy pressure such as pressure, touch, stretch, motion, and sound. Chemoreceptors include general receptors that monitor solute concentration and specific receptors that respond to important molecules. Response to different forms electromagnetic energy is caused by electromagnetic receptors. The forms of electromagnetic energy can be visible light, electricity, and magnetism. Thermoreceptors are found in the skin and hypothalamus. These receptors respond to either heat or cold and help maintain body temperature. Pain receptors are naked dendrites in the epidermis. They respond to excess heat, pressure, or chemicals released by injured or inflamed cells.

Conjoined Twins

I am super fascinated in human development. I actually want to pursue a career in Obstetrics. We know that a woman releases an egg, which can then be fertilized by a sperm. Sometimes women have more than one baby at a time. TWINS!!! This occurs two ways, when the fertilized egg divides and separates you have identical twins (same sex) or the woman may release two eggs at the same time that are fertilized by separate sperm, then you have fraternal twins. But there are some instances where the one egg of identical twins doesn’t quite separate equally. These children are called conjoined twins. Conjoined twins are extremely rare, they occur in one and every 200,000 births. Male conjoined twins are more likely to occur in the womb than female, but for some reason female conjoined twins are more likely to survive. About 70% of female conjoined twins born are female. And nobody knows why? Although having conjoined twins is a serious matter, their prognosis is become a lot brighter than in recent years. They can live well into their 60’s, and 200 separations have been performed, where 75% of the time one or both twins survive. Hopefully someday scientists can figure out ways to prevent the conjoining of twins, and give the children longer lives : )

Circulatory System

Diffusion alone is not sufficient enough for the transporting of substance over long distances. The time it takes for a substance to diffuse from one place to another over a long distance is proportional to the square of that distance. The circulatory system solves this problem. The circulatory system rapidly transports fluids in bulk throughout the body. This system exchanges gases, absorbs nutrients, and disposes waste. The vertebrate circulation is called the cardiovascular system. The heart pumps blood through the blood vessel channels and delivers it to various parts of the body. Arteries carry blood away from the heart. They divide up into aterioles which are small blood vessels. From aterioles capillaries are formed. They are the smallest vessel to carry oxygenated blood. Different species of vertebrates have slightly different heart forms. Fish have a two chambered heart. Amphibians and reptiles have a three chambered heart. Mammal and birds have a four chambered heart. These hearts may have different structures but they all provide basically the same function.

The path blood flows through the body !

Deoxygenated blood passes through the superior and inferior vena cava into the right atrium of the heart. Blood then flows into the right ventricle, which pumps it to the lungs via the pulmonary arteries. Oxygenated in the lungs, the blood flows through the pulmonary veins back into the left atrium of the heart, then into the left ventricle, from which it is pumped to the entire body via the aorta. Arteries carry blood away from the hear, breaking down into a network of arterioles. Veins arise from a network of venules to bring blood toward the heart. Between arterioles and venules are capillaries, tiny vessesla where cellular exchange (gases, nutrients, wastes) occurs. The lymphatic system returns lost fluid to the blood. Lymph fluid can intermingle with blood along lymph capillaries, which run alongside circulatory capillaries. Lymph nodes filter the lymph fluid by the action of white blood cells, protective cells that attack and isolate foreign bodies. Hope you enjoyed the quick overview of the circulatory system =]