Anatomy and Physiology: Body Structures, Functions, and Imaging Techniques

anatomy

the study of structures and the relationship among structures

gross anatomy

study of large structures

visible with the naked eye

ex: organs, bones

regional anatomy

study of specific regions of the body

ex: neck, abdomen

systemic anatomy

studies the anatomy of individual body system

ex: nervous system

surface anatomy

study of markings on the surface of the body to identify underlying structures

ex: blood vessels on the top of your hand

microscopic anatomy

study of things we cannot see with the naked eye

cytology

study of cells

histology

study of tissues

developmental anatomy

study of development from fertilization to death

embryology

study of the embryo which is considered anything before birth

pathological anatomy

study of changes in structure due to disease/illness

ex: looking at smoker/nonsmoker lungs

radiographic anatomy

study of anatomy using specialized screening technologies to allow us to see inside the body

ex: x-ray

x-ray

- light energy: short wavelength (gamma radiation)

- allows us to see dense structures like bone, not good for soft tissue

ex: broken bone

Computerized tomography (CT)

- light energy

- allows you to see layers of body

- creates a cross sectional plane from a number of different perspectives, bone appears brights

ex: fractures in bone

Xenon CT

- light energy

- xenon gas is inhaled

- lights up active areas which get the most blood flow

-does not show tissues only blood flow

- most active color: red

- least active color: blue

Dynamic Spatial Reconstruction (DSR)

-light energy

- creates a 3-D image, as pictures are taken around the body 360 degrees

ex: blood flow thru the heart

Digital Subtraction Angiography (DSA)

-light energy

- a contrast medium that is injected

- requires before and after image, subtracts the 2 so we can view blood vessels

ex: clots in blood vessels

Positron Emission Tomography (PET)

-light energy

-radioactive isotopes are injected

- allow us to examine metabolic activity

-no tissue, only color

ex: detect if cancer spreading

Ultrasound

-sound energy

-can be used to view soft tissue

-most commonly used for gestational images

Magnetic Resonance Imaging (MRI)

-magnetic energy

- uses H+ ions which allows us to view soft tissue in high clarity

- doesn't allow us to see bone/hard tissue

ex: ACL tears

Magnetic Resonance Spectroscopy (MRS)

-magnetic energy

-uses ions other than hydrogen to view different tissues

-calcium ions look at bones and muscles

-sodium ions look at kidneys

M2A

- light energy

-pill cam

- looks at digestive tract

-camera gets destroyed by acid in the stomach

-enters body through ingestion

Physiology

study of the functions of body parts including chemical and physical processes

Structure and function correlation

Structure can dictate function, and function can regulate strucuture

Levels of organization

chemical, cellular, tissue, organ, organ system, organismic

Cell

basic structure and functional unit of life

Tissue level

2 or more types of cells working together for common function

Organ level

2 or more tissues working together for a task

Organ System Level

2 or more organs working for a task

Organismal level

2 or more organ systems working together

Limiting boundary

separate the internal from the external world

ex: skin

Excitability

the ability to detect changes both within and outside the body

-response to stimuli

-ex: change in temp in the body

Conductivity

the ability to communicate the effects of a stimuli from one part of the body to another

ex: nervous system

Metabolism

the sum total of all the chemical reactions within the body

Catabolism

-break down reactions

- big things become small things

ex: break down food

Anabolism

-built up reactions

- small things become big things

ex: amino acids to proteins

Digestion

-the break down of food

- involves catabolic activity and absorption

Excretion

-elimination of wastes

- including fecal material, urine, urea, carbon dioxide, and perspiration

Movement

-the result of muscle activity, both involuntary and voluntary

-movement aka locomotion

Growth

increase in size or number of cells

Reproduction

replacement of one cell by another through mitosis or procreation

Nutrients

-survival need

chemical substances that our body uses for energy or the production of new cells

- obtained through balanced diet

Oxygen

-survival need

-final electron acceptor that helps us release the energy needed to keep us alive

Water

-survival need

-the most important and abundant substance in our body

-obtained in food and drink

-lost through evaporation and urination

Normal body temp

-survival needs

- normal temp= 37 C or 98.6 F

- too high= denatures proteins

- too low= slows down metabolism

Atmospheric pressure

- survival need

-on earth air exerts a force on our body

-makes it possible for us to breathe

Homeostasis

condition of a stable internal body environment

- never constant rather a dynamic equilibrium

Homeostasis requirements

-survival needs are at optimum

-within a narrow range

- when outside range, we try to bring it back in

Stresses/Stressors

-any stimulus causing an imbalance in the internal environment and disrupts homeostasis

-not all stimuli are stressors but all stressors are stiumli

Feedback system

a circular process that occurs in the body after homeostasis is disrupted and/or a stressor brings an imbalance that serves to reach homeostasis again

Nervous system regulation

-uses electrical messages

-responds quickly and is short lived

Endocrine system regulation

-uses chemical messages

- responds slowly and is long lived

Stimulus

something that causes an organism to respond and change its behavior, such as a stressor which causes an imbalance in homeostasis

Receptor

detects that homeostasis has been lost

Control center

causes an action

Effector

carries out the action which counteracts the stress to return to homeostasis

Negative feedback

-the effector's response reverses the original condition

ex: shivering when cold

Positive feedback

the effectors response intensifies the original condition

ex: childbirth

Matter

- anything that occupies space and has mass

- composed of chemical elements

Weight

mass x gravity

elements

Substances that cannot be broken down into simpler substances

- number of chemical elements

-number of elements that occur naturally

- number of natural elements human body contains

- 118

- 92

- 24

-Carbon + Oxygen + Nitrogen + Hydrogen

- Plus phosphorus and calcium

- the remaining 1% are called..

- 96%

-99%

- trace elements

Solids

-have definitive volume and shape

- slow speed

ex: bones, teeth

Liquids

- has a definitive volume but not a definitive shape

- medium speed

ex: blood

Gas

- does not have definitive shape of volume

- high speed

ex: air in lungs

Energy

- ability to do work and put matter into motion

potential energy

stored energy

ex: top of roller coaster

Kinetic energy

the energy of motion

ex: roller coaster down hill

Chemical energy

the energy that is contained in chemical bonds between atoms

Break bonds

release energy

Create bonds

form energy

What is the energy currency of the body

ATP (adenosine triphosphate)

To store energy

phosphorus is added to ADP to make ATP

To release energy

phosphorus is taken off of ATP to make ADP

Electrical energy

results from the flow of charged particles

ex: neural impulses

Electrolytes

charged particles in the body

- called salts in our body

Mechanical energy

-the energy required for motion/movement

- when an objects potential energy is combined with its kinetic energy

ex: muscle movement

Electromagnetic energy

- referred to as radiant energy

- travels in waves

ex: MRI, heat, light

Law of thermodynamics

-Energy cannot be created or destroyed, only transformed

-no energy is 100% complete. some energy will be lost as heat which is then used to maintain our body temp

Atom

-smallest unit of matter that can enter a chemical reaction

-all elements composed of atoms

- atoms allow elements to react with other elements

Nucleus

-center of the atom which makes up most of its mass

Electrons

- float around the nucleus, constantly in motion, carry negative charge

Atomic number

number of protons and equal to number of electrons

Atomic mass

sum of number of protons plus number of neutrons

Isotope

an atom that contains the same number of protons and electrons but a different number of neutrons

-these are unstable and have neutral charge

Energy levels

-regions in which the electrons move around the nucleus

- known as orbitals

-first shell holds 2

-rest hold 8

Valence level

-outermost energy level

Valence electron

-number of extra or deficient electrons in the valence level

- full shell: not reactive

-not full shell: reactive

Chemical reactions

-combining or breaking apart of atoms forming new products with different properties from the originals

-atoms try to fill their outermost energy level

-accomplished by donation, accepting, or sharing electrons

Molecule

a combination of two or more atoms

Compound

2 or more different elements

- can be broken down by chemical means

Compound and molecule connection

All compounds are molecules but not all molecules are compounds

Chemical bonding

attractive forces that hold together the atoms of a molecule

Ionic bond

result when ions of opposite charges are attracted to one other

- one atom gains electrons and the other loses electrons

Covalent bond

-occur when atoms share electrons

- can be single, double, triple depending on number of pairs of electrons

Polar covalent

unequal sharing of electrons

dissolve in water

Nonpolar covalent

- equal sharing of electrons

-doesn't dissolve in water

-more common and stable in human body than ionic

Hydrogen bond

weak attractive force between hydrogen atom bonded to one electronegative atom on an adjacent molecule

- partial postive and partial negative

Synthesis reaction

- 2 or more smaller things make 1 big thing

- anabolic

ex: a+b-> AB