A and P Honors

A and P Honors

• Chapter 1

Overview of Anatomy and Physiology

• AnatomyAnatomy – the study of the structure of body parts and their relationships to one another– Gross or macroscopic– Microscopic– Developmental

• PhysiologyPhysiology – the study of the function of the body’s structural machinery

Gross Anatomy

• RegionalRegional – all structures in one part of the body (such as the abdomen or leg)

• SystemicSystemic – gross anatomy of the body studied by system

• SurfaceSurface – study of internal structures as they relate to the overlying skin

Microscopic Anatomy

• CytologyCytology – study of the cell

• HistologyHistology – study of tissues

Developmental Anatomy

• Traces structural changes throughout life

• EmbryologyEmbryology – study of developmental changes of the body before birth

Specialized Branches of Anatomy

• Pathological anatomyPathological anatomy – study of structural changes caused by disease

• Radiographic anatomyRadiographic anatomy – study of internal structures visualized by X ray

• Molecular biologyMolecular biology – study of anatomical structures at a sub-cellular level

Physiology

• Considers the operation of specific Considers the operation of specific organ systemsorgan systems– Renal – kidney function– Neurophysiology – workings of the nervous

system– Cardiovascular – operation of the heart and

blood vessels

• Focuses on the functions of the body, Focuses on the functions of the body, often at the cellular or molecular leveloften at the cellular or molecular level

Physiology

• Understanding physiology also requires a knowledge of physics, which explains electrical currents, blood pressure, and the way muscle uses bone for movement

Principle of Complementarity

• Function always reflects structure

• What a structure can do depends on its specific form

Chemical levelAtoms combine to form molecules

1

2

3

4

Cellular levelCells are made up of molecules

Tissue levelTissues consist of similar types of cells

5 Organ system levelOrgan systems consist of different organs that work together closely

Organ levelOrgans are made up of different types of tissues

6 Organismal levelThe human organism is made up of many organ systems

Atoms

Molecules

Smooth muscle cell

Smooth muscle tissue

Connective tissue

Smooth muscle tissue

Epithelial tissue

Blood vessel (organ)

Heart

Blood vessels

Cardiovascular system

Levels of Structural Organization

Figure 1.1

Levels of Structural Organization• ChemicalChemical – atoms combined to form molecules

• CellularCellular – cells are made of molecules

• TissueTissue – consists of similar types of cells

• OrganOrgan – made up of different types of tissues

• Organ systemOrgan system – consists of different organs that work closely together

• OrganismalOrganismal – made up of the organ systems

Homeostasis

• HomeostasisHomeostasis is the ability to maintain a relatively stable internal environment in an ever-changing outside world

• The internal environment of the body is in a dynamic state of equilibriuma dynamic state of equilibrium

• Chemical, thermal, and neural factors interact to maintain homeostasis

Homeostatic Imbalance

• Disturbance of homeostasis or the Disturbance of homeostasis or the body’s normal equilibriumbody’s normal equilibrium

• Overwhelming of negative feedback mechanisms allowing destructive positive feedback mechanisms to take over

Homeostatic Imbalance

• Can lead to disease.

• Diabetes is a homeostatic imbalance.

Positive and negative feedback

• Biological systems contain many types of regulatory circuits, among which positive and negative feedbacks. Positive and negative don't imply consequences of the feedback have positive or negative final effect. The negative feedback loop tends to slow down a process, while the positive feedback loop tends to accelerate it.

An example of a simple negative feedback loop

What if you get cold?

Positive Feedback Mechanisms

Homeostatic systems utilizing positive feedback exhibit two primary characteristics:

1. Time limitation – Processes in the body that must be completed within a constrained time frame are usually modified by positive feedback.

2. Intensification of stress – During a positive feedback process, the initial imbalance or stress is intensified rather than reduced as it is in negative feedback.

Typical Positive Feedback Process

Stress Sensor Control Center

EffectorIntensifies

Homeostatic Regulation of Child Birth through Positive Feedback

Pressure of Fetus on the Uterine Wall

Nerve endings in the uterine wall carry afferent messages

to the Hypothalamus

Production and Release of Oxytocin into the

BloodIncreasing strength of uterine contractions

Intensifies

The birth of the child will bring this process to a close. Other examples of positive feedback regulation occur during milk letdown and blood clotting.

Positive feedback “mini-loops” are built into pathway to speed up production of chemicals needed to form the clot. Entire sequence of clotting is a negative feedback pathway:

Feedback in Coagulation

Anatomical Position

• Body erect

• Feet slightly apart

• Palms facing forward

• Thumbs point away from body

Figure 1.7a

Directional Terms

• Superior and inferiorSuperior and inferior – toward and away from the head, respectively

• Anterior and posteriorAnterior and posterior – toward the front and back of the body

• Medial, lateral, and intermediateMedial, lateral, and intermediate – toward the midline, away from the midline, and between a more medial and lateral structure

Directional Terms

• Proximal and distalProximal and distal – closer to and farther from the origin of the body

• Superficial and deepSuperficial and deep – toward and away from the body surface

Directional Terms Table 1.1

Directional Terms Table 1.1

Regional Terms: Anterior View

• AxialAxial – head, neck, and trunk

• AppendicularAppendicular – appendages or limbs

• Specific Specific regional regional terminologyterminology

Figure 1.7a

Regional Terms: Posterior View

Figure 1.7b

Body Planes• SagittalSagittal – divides the body into right and

left parts

• Midsagittal or medialMidsagittal or medial – sagittal plane that lies on the midline

• Frontal or coronalFrontal or coronal – divides the body into anterior and posterior parts

• Transverse or horizontalTransverse or horizontal (cross section) – divides the body into superior and inferior parts

• Oblique sectionOblique section – cuts made diagonally

Body Planes Figure 1.8

Anatomical Variability

• Humans vary slightly in both external Humans vary slightly in both external and internal anatomyand internal anatomy

• Over 90% of all anatomical structures match textbook descriptions, but:

– Nerves or blood vessels may be somewhat out of place

– Small muscles may be missing

• Extreme anatomical variations are Extreme anatomical variations are seldom seenseldom seen

Body Cavities

Figure 1.9a

Body Cavities• Dorsal cavityDorsal cavity protects the nervous system,

and is divided into two subdivisions

– Cranial cavity is within the skull and encases the brain

– Vertebral cavity runs within the vertebral column and encases the spinal cord

• Ventral cavityVentral cavity houses the internal organs (viscera), and is divided into two subdivisions: - Thoracic and Abdominopelvic cavities

Body CavitiesFigure 1.9b

Body Cavities

• Thoracic cavityThoracic cavity is subdivided into pleural cavities, the mediastinum, and the pericardial cavity

– Pleural cavities – each houses a lung

– Mediastinum – contains the pericardial cavity, and surrounds the remaining thoracic organs

– Pericardial cavity – encloses the heart

Body Cavities• The abdominopelvic cavity is separated The abdominopelvic cavity is separated

from the superior thoracic cavity by the from the superior thoracic cavity by the dome-shaped diaphragmdome-shaped diaphragm

• It is composed of two subdivisions

– Abdominal cavity – contains the stomach, intestines, spleen, liver, and other organs

– Pelvic cavity – lies within the pelvis and contains the bladder, reproductive organs, and rectum

Ventral Body Cavity Membranes

• Parietal serosaParietal serosa lines internal body walls

• Visceral serosaVisceral serosa covers the internal organs

• Serous fluid separates the serosae


Figure 1.10a


Figure 1.10b

Other Body Cavities

• Oral and digestiveOral and digestive – mouth and cavities of the digestive organs

• NasalNasal –located within and posterior to the nose

• OrbitalOrbital – house the eyes

• Middle earMiddle ear – contain bones (ossicles) that transmit sound vibrations

• SynovialSynovial – joint cavities

Abdominopelvic Regions

• Umbilical

• Epigastric

• Hypogastric

• Right and left iliac or inguinal

• Right and left lumbar

• Right and left hypochondriac

Figure 1.11a

Organs of the Abdominopelvic Regions

Figure 1.11b

Abdominopelvic Quadrants

• Right upper (RUQ)

• Left upper (LUQ)

• Right lower (RLQ)

• Left lower (LLQ)

Figure 1.12

Cellular Metabolism

• Cellular metabolism refers to all of the chemical processes that occur inside living cells.

Cellular Metabolism

Metabolic processes – all chemical reactions that occur in the body

Two types of metabolic reactions

Anabolism• larger molecules are made• requires energy

Catabolism• larger molecules are broken down• releases energy

Fates of Organic Building Blocks in

ATP Metabolis

m

ORGANIC BUILDING BLOCK MOLECULESMonosaccharides

Amino acidsAcetates

Nucleotide bases

Polymers &

other energy

rich molecules

CO2

&H2O

anabolic processes

catabolic processes

ATP

ADP+Pi

energyenergy

What Effects our Metabolism?

1.Genetics

2.Age

3.Weight

4.Body Composition

5.Eating Frequency

6.Exercise

7.Nutrition

↓↑

↓

↑

↑

↑

↑

↑

Calories Burned with Exercise/ Activity

– Sleeping 55– Watching TV 72– Eating 85– Sitting 85– Standing 100– Driving 110– Housework,

moderate 160+

– Golf, with cart 180– Golf, without cart 240– Walking 2mph 240– Dancing, ballroom 260– Walking, 3mph 280– Table Tennis 290– Mowing the Lawn 324

•Type of ExerciseCalories/hour

Calories Burned per hour

– Skiing 340+– Tennis 350+– Water Aerobics 400– Skating/blading 420+– Dancing, aerobic 420+– Aerobics 450+– Bicycling, moderate

450+– Soccer 460+– Jogging, 5mph 500

– Swimming, active 500+– Cross country ski

machine 500+ – Hiking 500+ – Step Aerobics 550+– Rowing 550+– Power Walking 600+– Cycling, studio 650– Skipping with rope

700+– Running 700+

Kinetics

• Force: push or pull that tends to produce acceleration

• Important factor in injuries

• Vector

Kinetics

• Idealized force vector• Force couple system

d=

d

FF

F

F’

=

d

F

M=Fd

Pressure

• P = F/A• Units (Pa = N m2)• In the human body

also called stress• Important

predisposing factor for injuries

Moments of Force (Torque)

• Effect of a force that tends to cause rotation about an axis

• M = F ·d (Nm)– If F and d are

• Force through axis


• Force components– Rotation– Stabilizing or

destabilizing component


• Net Joint Moment– Sum of the moments

acting about an axis

• Human: represent the muscular activity at a joint– Concentric action– Eccentric action– Isometric

Classifying Forces• Internal Force: acts within the object or system

whose motion is being investigated– action / reaction forces both act on different

parts of the system • tensile-internal pulling forces when the structure is under

tension• compressive- internal pushing (squeezing) forces act on the

ends of an internal structure

– do not accelerate the body• Orientate segments, maintain structural integrity

Classifying ForcesExternal Force: acts on object as a result of

interaction with the environment surrounding itnon-contact - occur even if objects are not

touching each othergravity, magnetic

contact - occur between objects in contact fluid (air & water resistance)reaction forces with another body (ground, implement) vertical (normal) reaction force

acts perpendicular to bodies in contactshear reaction force

acts parallel to surfaces in contact (friction)

Torque and length of lever arms

• In humans, contracting muscle applies an eccentric force (not to be confused with eccentric contraction) to bone upon which it attaches & causes the bone to rotate about an axis at the joint

• Amount of torque is determined by multiplying amount of force (force magnitude) by force arm

Mechanical loads on the Human Body

• The skeletal system is subjected to a variety of different forces so that bone is loaded in various directions. These are loads produced by gravity, weight bearing, muscle, and external forces

• Compression• Tension• Shear • Mechanical Stress

A compressive force presses the ends of the bones togetherand is produced by muscles, weight bearing, gravity, or some external loading down the length of the bone

Tensile force is a pulling forcethat creates tension in the object/body-tends to lengthen and narrow-source is usually muscle

Shear Forces

• A 3rd category of force• While compressive and

tensile forces act along the longitudinal axis of the bone or other body, shear forces act parallel or tangent to the surface

• Tend to cause one portion to slide or displace

This position places a large amount of stress on the ligaments and tendons that prevent the femur from sliding off the tibial plateau

Squat or Knee Bend

Shear Force

Stress and Strain

• Another way of evaluating the behavior of bone or any other material when subjected to loading is to measure the stress, or load per cross-sectional area, or the strain or deformation with respect to the original length of the material.

63

Stress = Load per cross sectional area .-resulting force distribution as a result of an external force

Strain = deformation with respect to the original length

Normal Strain – change in length

Shear Strain – change in angle

Angle Length In length

What Does The Research Show?• % Load Compression On L3 During the Upright Standing, Lying Down, and Sitting.

• Compression Increases More with Spinal Flexion, and Increases Still Further with a Slouched Sitting Position.

Types of stress

• Tensile stress-tissue separation

• Compressive- pressed together

• Shearing-tangential force

TISSUE LOADS

• Compressionis when an external force tends to squeeze the molecules of a material together.

• Tension is when the load acts to stretch or pull apart the material.

• Shear is a right-angle loading acting in opposite directions.

• A trainer creates a shearing load across athletic tape with scissor blades or their fingers when they tear the tape.

• When many forces are acting on a body they can combine to create combined loads called torsion and bending In bending one side of the material is loaded in compression while the other side experiences tensile loading. When a person is in single support in walking (essentially a one-legged chair), the femur experiences bending loading. The medial aspect of the femur is in compression while the lateral aspect is in tension.

Steps in the Scientific Steps in the Scientific MethodMethod

• ObservationObservation• HypothesisHypothesis• ExperimentExperiment• Data CollectionData Collection• ConclusionConclusion• RetestRetest

DataData

•Results of the experiment

•May be quantitative (numbers) or qualitative

Theory defined

• An explanation based on many observations during repeated experiments that is valid only if it is consistent with observations, makes predictions that can be tested, and is the simplest explanation.

• A logical, time tested explanation for events that occur in nature.

Beginnings

• Aristotle (384 BCE-322 BCE or BC)• ancient Greek philosopher

Aristotle

• Aristotle, more than any other thinker, determined the orientation and the content of Western intellectual history. He was the author of a philosophical and scientific system that through the centuries became the support and vehicle for both medieval Christian and Islamic scholastic thought: until the end of the 17th century, Western culture was Aristotelian. And, even after the intellectual revolutions of centuries to follow, Aristotelian concepts and ideas remained embedded in Western thinking.

Claudius Galen – The Early Years

• Born in Greece (Turkey) 131AD

• Trained in Alexandria– 152 – 157

• Worked at Asclepion– 157 - 162

• Went to Rome to make his Fortune– 162

• Gladiator School– 162 - 166

• Showman– Page 43

Why is Galen Important

• Galen was not famous for having new groundbreaking ideas. Rather, he was famous for improving upon and communicating existing Greek ideas– Four Humours– Anatomy– Physiology– Design– Writings

An Artist and a Scientist

• Because Leonardo the artist sought for the ideal face, he skillfully sliced open the skull to reveal the brain cavity and see what lay beneath. Combining art and science he analyzed the proportions of the head.

An Artistic and Scientific Search for the True Picture of Man and his

Universe

• "Leonardo da Vinci was like a man who awoke too early in the darkness, while the others were all still asleep"

-Sigmund Freud

Andreas Vesalius

By:

January 2009

Early Life

• Born December 31st 1514 in Brussels, Belgium.

• Vesalius showed an early interest in anatomy, and came from a family that had studied medicines for generations before him.

Galen vs. Vesalius

• During his dissections, Vesalius was able to show without question that there were vital errors in Galen’s studies of the human body.

• Vesalius concluded that this was due to the fact that in the ancient days of Galen, human dissections were not permitted.

• This lead Galen to do all of his studies on animals and from these studies make theories as to how the human body functioned. Even after this discovery, Vesalius credited Galen with most of discoveries of the human body.

Vesalius’ Magnum Opus

• In order to attract more attention to the science that he had devoted his life, Vesalius gave 5 years of his life working on the “De Humani Corporis Fabrica”.

• This was an amazingly in depth description of his studies on the human body.

• It included detailed sketches, descriptions, as well as instructions on how to perform a dissection of the human body.

• This book was labeled the first textbook on anatomy, and is considered one of the most important books in medical history.

Who Was William Harvey?

• Born 1578 (England)

• Died 1657

• Specialism: Circulation of blood

Before Harvey

• People believed in Galen’s theory that blood was produced in the liver. Galen believed that blood was burnt up by the body. Other writers had questioned this theory but they had struggled to prove it wrong.

After Harvey

• Harvey proved that blood flows around the body. He stated that blood was carried away from the heart by arteries and returns to the heart through veins.

• Harvey proved that the heart is a pump that recirculates the blood and that blood wasn’t ‘burnt up’.

Harvey’s Methods

• Harvey was very scientific in his methods. These included:

• Dissecting cold blooded animals (e.g. reptiles) to observe the movement of muscle around the heart.

• Dissected humans to gain a knowledge of the heart.

• Used iron rods to prove that blood was pumped through veins in one direction.

• He accurately calculated the amount of blood in the body.

Robert Hooke

The English Father of Microscopy

Inventor• Modern Air Pump• Flying Machines• Conical Pendulum• Helioscope• Reflecting Telescope• Wheel Barometer• Spring Control• Universal Joint• Compound Microscope

Cells

• Coined the term “cell” in a biological context.

• Believed that “cells” only existed in plants since he had only observed them in plant material.

• Why do you think Hooke only saw “cells” in plants? What structure was he seeing?

History of the Microscope

• In the late 1600’s, Anton Van Leeuwenhoek became the first person to make and use a real microscope.


• Anton Van Leeuwenhoek achieved even greater success than his peers by making superior lenses. He polished & ground up 550 lenses to make a lens tube with a magnification of 270x – others were lucky to achieve 50x with their microscopes!


• Anton Van Leeuwenhoek was the first to see bacteria, yeast, and life found in a drop of pond water. He found extraordinary things using his microscope throughout his lifetime.

• Here’s a look at a virtual drop of pond water:

http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/ponddip/index.html

Documents

A and P Honors