Download Biology 11 – Human Anatomy Lecture

Anatomy 30 – Anatomy & Physiology Lecture
Human Body Orientation
I. Overview
A. Overview of Anatomy & Physiology
B. Structural Organization
C. Organ Systems
D. Life Maintenance Mechanisms
E. Homeostasis and Feedback
II. Overview of Anatomy & Physiology
A. Anatomy (to cut up, or dissect) is the study of body structures and
their relationships.
1. Morphology is the science of form.
2. Physiology (study of nature) is the study of body functions.
Anatomy is intimately intertwined with physiology – structure
reflects function.
3. Anatomical terminology - learning the word roots inside the
text back cover quickly will help you immensely.
B. Topics of Anatomy
1. Gross Anatomy is the study of body structures that can be
observed with the naked eye. Dissection is used to study gross
anatomy
2. Regional Anatomy - study of structures in a particular body
region (e.g.: head or neck). Often used by med. schools.
3. Systemic Anatomy - study of organs with related functions
(i.e.: within a body system). We will use this approach.
4. Surface Anatomy deals with surface features that can be
observed beneath the skin or palpated (examined by touch)
5. Microscopic Anatomy is concerned with structures smaller
than 0.1 mm that can only be seen with a microscope.
Anatomical sciences that require microscopes include:
a. Cytology - the study of cells
b. Histology - the study of tissues
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C. Topics of Physiology
1. Physiology concerns the functions of specific organs or organ
systems. Examples include:
a. Cardiovascular physiology examines the operation of the
heart and blood vessels
b. Neurophysiology attempts to explain how the nervous system
works
2. Physiology is initiated on a cellular level, and is based upon
physical and chemical interactions within and among cells
III. Levels of Structural Organization
atoms  molecules  organelles  cells  tissues  organs 
organ systems  organism
A. Cellular Level
1. Minute particles called atoms bond together to form molecules;
Four classes of macromolecules form cells:
a. Carbohydrates (sugars)
b. Lipids (fats)
c. Proteins
d. Nucleic acids (DNA & RNA)
2. Molecules group together in specific ways to form organelles,
functional structures within cells
a. Each organelle carries out specific functions in the cell
b. The nucleus, mitochondrion, and ER are examples of
organelles
3. A cell is the basic structural and functional component of life
a. Humans are composed of 60-100 trillion cells
b. Metabolism, growth, responsiveness, repair, and replication
are carried on at the cellular level
4. Organelles and cytoplasm surrounded by a plasma membrane
compose a cell
a. The human body contains many distinct types of cells, each
specialized to perform specific functions (e.g.: skin, bone,
fat, blood, & muscle cells)
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b. The structure of each cell type is related to its function
B. Tissue level
1. Tissues are layers or groups of similar cells that perform a
common function. The body is composed of 4 major kinds of
tissues:
a. Epithelial - covers & lines body surfaces
b. Connective – supports and protects body organs
c. Muscular – provides movement
d. Nervous – allows rapid internal communication via electrical
nerve impulses
2. Histology is the microscopic study of tissues
C. Organ level
1. An organ is an combination of 2 or more tissue types that
performs a specific function
2. Examples include the heart, liver, pancreas, bones, skin, etc.
3. Each organ has one or more primary tissues and several
secondary tissues
a. In the stomach, the inside epithelial lining is the primary
tissue because it is involved with secretion and absorption
b. Secondary tissues of the stomach are the connective,
vascular, nervous, and muscle tissues
D. System level
1. A body system consists of various organs that have similar or
related functions
2. The 11 major systems of the body and their functions include:
a. Integumentary - external support and protection of the body;
vit. D synthesis; has sense receptors, sweat, & oil glands
b. Skeletal - internal support and flexible framework for body
movement; blood cell production; stores minerals
c. Muscular - body movement; heat production
d. Nervous - control and regulation of all other systems of the
body; activates muscles & glands
e. Endocrine - secretion of hormones for chemical regulation
of growth, metabolism, reproduction, etc.
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f. Cardiovascular - transports oxygen, nutrients, hormones to
body cells; removes metabolic wastes & CO2 from cells
g. Lymphatic - body immunity; absorption of fats; returns
tissue fluid to the blood
h. Respiratory - supplies oxygen to blood; removes carbon
dioxide from blood
i. Digestive - breakdown and absorption of food materials;
undigested matter eliminated as feces
j. Urinary - eliminates nitrogenous wastes from the body;
regulates water, electrolyte, & acid-base balance
k. Reproductive
1) Female - production of female sex cells (ova); receptacle
for sperm from male; site for fertilization of ovum;
implantation, and development of embryo and fetus;
delivery of fetus
2) Male - production of male sex cells (sperm); transfer of
sperm to female reproductive system
IV. Maintaining Life
A. Necessary Life Functions include the following:
1. Maintenance of boundaries between the external surroundings
and the internal environment. What structures provide this?
2. Movement of our bodies, as well as materials such as blood,
food, urine, etc., within our bodies. What tissues are involved?
3. Responsiveness – the ability to sense changes (stimuli) in the
environment and react to them. What system is most involved?
4. Digestion – the breakdown of ingested food into simple
molecules, which are absorbed into the bloodstream. What two
systems are most involved?
5. Metabolism – all chemical reactions within our cells; 2 types:
a. Anabolism – building smaller molecules into larger ones
b. Catabolism- breaking large molecules into smaller ones
6. Excretion of wastes from the body. What 3 systems are most
involved?
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7. Reproduction at both the cellular and organismal levels
a. Organismal level - sperm unites with an egg
b. Cellular reproduction involves mitosis or meiosis
1) Mitosis results in two genetically identical daughter cells,
which are used in growth and repair
2) Meiosis occurs in the formation of gametes (sperm and
eggs)
8. Growth – an increase in the size of an organism, usually by
increasing the number of cells. What process allows this?
B. Survival Needs include oxygen, water, nutrients, normal body
temperature, and atmospheric pressure
1. Nutrients, acquired from foods, contain chemicals needed for
a. Energy production (ATP molecules)
b. Organic building materials (e.g.: monosaccharides, fatty
acids, amino acids, nucleic acids) for cells and growth
c. Vitamins & minerals for chemical reactions
2. Oxygen is needed for chemical reactions that produce ATP
energy from nutrients
3. Water (H2O) is obtained from food and drink, and lost via
breathing, sweating, and bodily excretions. Functions:
a. The most abundant inorganic substance in the body
b. Universal solvent – dissolves water-based substances
c. Allows metabolic/biochemical reactions
d. Transports substances within the body
4. Normal Body Temperature (37C) is maintained mainly by
muscle metabolism, and is essential for chemical reactions.
a. Low body temperature slows metabolic reactions
b. High body temperature can denature enzymes
5. Atmospheric pressure is the force that air exerts on our body
surface; needed for breathing and gas exchange in the lungs.
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V. Homeostasis and Feedback
A. Homeostasis is the maintenance of a relatively stable internal
environment
1. Physiology is a group of mechanisms for maintaining
homeostasis, or dynamic equilibrium
2. Dynamic equilibrium describes the way in which body
conditions fluctuate within a narrow range, then return to a set point
B. Negative Feedback and Stability
1. Negative feedback – the body senses a change and activates
mechanisms that negate or reverse it
2. Common example: a thermostat is activated when the
temperature drops below the set temp., the heater turns on and
brings the temp. up, the thermostat turns off
3. Body temperature example:
a. Body temperature increase triggers skin blood vessels to
vasodilate (widen) and sweating, which cools the circulating
blood, which cools the body down to normal temp.
b. Body temperature decrease triggers skin blood vessels to
vasoconstrict and shivering, which warms the circulating
blood, bringing body temperature up
4. Homeostatic control mechanisms include 3 components:
a. Receptor – structure that senses a change in the body and
sends info. to the
b. Control center – area that processes the incoming info. and
formulates an appropriate response and sends it to an
c. Effector – structure that carries out the response and restores
homeostasis
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C. Positive Feedback and Rapid Change
1. Positive feedback– physiological change that leads to greater
change in the same direction
2. Example: during childbirth oxytocin release from the
hypothalamus stimulates increasing labor contractions until the
baby is born