What is anatomy and what is physiology?
Anatomy is the study of structure while physiology is the study of function. Anatomy makes physiology possible while physiology lends meaning to anatomy. There is a unity of form and function.
What is gross anatomy ?
Structures that can be seen with the naked eye, whether by surface observtion, radiology (the branch of medicine concerned with imaging), or dissection.
The functions of the body ultimately results from its _____________ _____. Histology is .......
Individual cells studying tissue specimens under the microscope (microscopic anatomy)
What is histopathology?
The microscopic examination of tissues for signs of disease
What is cytology?
The study of structure and function of individual cells
What is ultrastructure ?
Refers to fine detail, down to the molecular level, revealed by the electron microscope.
What is auscultation?
Listening to the natural sounds made by the body such as heart and lung sounds
What is palpation ?
feeling a structure with the hands such as palpating a swollen lymph node or taking a pulse.
Who was Andreas Vesalius ?
He was an anatomy professor of the 16th century in Italy who published the first atlas of anatomy, De Humani Corporis Fabrica (On the Structure of the Human Body)
Who was William Harvey?
A pioneer in physiology, an Englishman who in the 17th century realized that blood must circulate continuously around the body. This went against beliefs at the time.
The importance of cell theory.....
When in the 19th century, a couple scientists concluded that all organisms were composed of cells, this was pioneering and paved the way for cell theory......perhaps the most important breakthrough in biomedical history: all functions of the body are now interpreted as the effects of cellular activity.
The scientific method is concerned primarily with
how one thinks - it refers less to observational procedures than to certain habits of disciplined creativity, careful observation, logical thinking and honest analysis of ones observations and conclusions.
What is the inductive method?
The process of making numerous observations until one feels confident in drawing generalizations and predictions from them.
What is evolutionary medicine ?
Analyzes how human disease and dysfunctions can be traced to differences between the artificial environment in which we now live and the prehistoric environment to which Homen Sapiens was biologically adapted. For example, we can relate sleep and mood disorders to artificial lighting and night-shift work and the rise of asthma to our modern obsession with sanitation.
What is the hierarchy of complexity in humans?
Organism - organ systems- organs - tissues-cells - organelles- macromolecules - molecules- atoms
What is reductionism?
The theory that a large, complex system such as the human body can be understood by studying its simpler components.
What is holism?
Complementary theory of reductionism that says human beings are more than the sum of their parts- that there are emergent properties of the whole organism that cannot be predicted from the properties of its separate parts. To be most effective a health care provider treats not merely a disease or an organ system but a whole person.
What are characteristics of life ?
Organization - living things exhibit a far higher level of organization than the nonliving world around them- they expend a great deal of energy to maintain order Cellular composition- living matter is always compartamentalized into one or more cells
Metabolism- living things take in molecules from the enviroment and chemically change them into molecules that form their own structures, control their physiology or provide them with energy. Metabolism is the sum of all this internal chemical change and consists of two classes of reactions- anabolism (synthesis of complex molecules from simpler ones) and catabolism (breakdown of complex molecules into simpler ones) Excretion is also needed to get rid of the wastes that accumulate.
Responsiveness and movement- organisms sense and react to stimuli (changes in their enviroment) It occurs at all levels from the single cell to the entire body and it characterizes all living things from bacteria to you.
Homeostasis - the environment changes but the organism is able to maintain relatively stable internal conditions. The ability to maintain internal stability is called homeostasis.
Development- any change in form or function over the lifetime of organism. Involves differentiation - the transformation of cells with no specialized function into cells that are committed to a particular task and Growth - an increase in size. The growth of your body occurs through chemical change; for the most part your body is not composed of the molecules you ate but of molecules made by chemically altering your food.
Reproduction- all living organisms can produce copies of themselves nad pass their genes onto younger offspring
Evolution - all living things exhibit genetic change from generation to generation and therefore evolve. This occurs because mutations (changes in DNA structure) are inevitable and because environmental selection pressures favor the transmission of some genes more than others. Unlike the other characteristics of life, evolution is a characteristc seen only in the population as a whole. No single individual evolves over the course of its life
Why is it important to recognize that there are anatomical and physiological differences among different people?
Because there are. No human body is exactly the same in that everything is exactly in the same place or works the same way. Failure to consider such variation leads to medical mistakes such as overmedication of the elderly or medicating women on the basis of research that was done on young men.
What does the term dynamic equilibrium mean?
Describes the internal state of the body in that internal conditions are not absolutely constant but fluctuate around a certain set point or average value for a given variable such as 37o C for body temperature.
What is negative feedback and how does it relate to homeostasis?
Negative feedback mechanisms allow the body to maintain homeostasis or internal stability by keeping variables close to their set points.
In negative feedback, the body senses a changes and activates mechanisms that negate or reverse it. By maintaining stability, negative feedback is the key mechanism for maintaining health.
What are three common components of a feedback loop and what is an example of each?
The receptor - structure that senses a change in thebody, such as the stretch receptors that monitor blood pressure.
The integrating (control) center) such as the cardiac center of the brain, is a mechanism that processes this information, relates it to other available information (such as comparing what the blood pressure is with what it should be) and "makes a decision" about what the appropriate response should be.
The effector is the cell or organ that carries out the final corrective action. For blood pressure it would be the heart. The response such as the resoration of normal blood pressure is then senses by the receptor and the feedback loop is complete.
What is positive feedback?
A self amplifying cycle in which a physiological change leads to even greater change in the same direction, rather than producing the corrective effects of negative feedback.
Positive feeback mechanisms can be dangerous though because they can amplify their effect far past a homeostatic set point causing very dangerous internal conditions.
What is a physiological gradient?
A difference in chemical concentration, electricla charge, physical pressure, temperature, or other variable between one point and another.
If matter or energy moves from the poitn where this variable has a higher value to the point with a lower value we say it flows down the gradient- such as from a place of higher chemical concentration to one of lower concentration.
Movement in the opposite direction is up the gradient.
Matter and energy tend to flow down gradients. Differences in chemical concentration, pressure, temperature amd electrical charge account for much of the movement of matter and energy in physiology.
Give an example of a pressure gradient
Pressure that flows from an area of high pressure to an area of lower pressure.
Garden hose - water flows from the high pressure point at the tap to the low pressure point at the open end.
What kind of gradient do chemicals flow down?
Concentration gradients- chemicals flow from an area of high concentration to an area of low concentration
The cells lining the intestine contain only a low concentration of sugars so sugars flow from the intestinal space into these cells thus becoming absorbed into the body's tissues
What kind of gradient do charged particles flow down?
Electrical gradients - charged particles flow from areas of a high concentration of ions to areas of a low concentration of ions
Heat flows down a _________
Thermal gradient -
warm blood flowing through small arteries close to the skin surface and the air temperature around the body is cooler, then heat will flow from the blood to the surrounding air, down its thermal gradient and be lost from the body.