A&P Exam 1

anatomy

study of the structure or form of the body

physiology

study of the body’s functions

cellular composition

cells are the smallest units that carry out the functions of life

metabolism

living organisms carry out chemical processes collectively called metabolism

anabolism

building processes

catabolism

breaking down processes

growth

an increase in the size and/or number of cells

excretion

elimination of potentially harmful products created by metabolic processes

responsiveness or irritability

organisms sense and react to changes or stimuli in their environment

movement

organisms or individual cells of an organism move

reproduction

production of new cells during growth or repair or reproduction of new organisms

1st level of structural organization:

chemical

this is the smallest level; chemicals range from tiny atoms to complex molecules

2nd level:

cellular

groups of many different types of molecules combine in specific ways to form cellular structures

3rd level:

tissue

two or more cell types and material outside them, called extracellular matrix, combine to perform a function 

4th level:

organ

two or more tissue types combine to form an organ with a recognizable shape that performs a specialized task

5th level:

organ system

two or more organs that together carry out a broad function in the body

6th level:

organism

the organ systems function together to make up the working human body – an organism

integumentary system

• Protects the body from the external environment

• Produces vitamin D

• Retains water

• Regulates body temperature

skeletal system

• Supports the body

• Protects internal organs

• Provides leverage for movement

• Produces blood cells

• Stores calcium salts

muscular system

• Produces movement 

• Controls body openings 

• Generates heat 

nervous system

• Regulates body functions

• Provides for sensation, movement, automatic, functions, and higher mental functions via nerve impulses

endocrine system

• Regulates body functions

• Regulates the functions of muscles, glands, and other tissues through the secretion of chemicals called hormone

cardiovascular system

• Pumps and delivers oxygen-poor blood to the lungs and oxygen-rich blood to the tissues

• Removes wastes from tissues

• Transports cells, nutrients, and other substances

systemic anatomy

type of anatomy that examines individual organ systems

regional anatomy

type of anatomy that examines the body in regions, such as head and neck

surface anatomy

type of anatomy that examines surface markings

gross anatomy

type of anatomy examines structures that can be seen with the unaided eye

microscopic anatomy

type of anatomy examines cells (cytology) and tissues (histology) with the use of a microscope

cranial cavity (dorsal)

• brain

• layers - meninges (three protective connective tissue layers)

• cerebrospinal fluid

3 layers of meninges

dura mater, arachnoid mater, pia mater

spinal cavity (dorsal)

• spinal cord

• layers - meninges as well

• cerebrospinal fluid (CSF)

(thoracic cavity ventral)

pleural cavities

• both on left and right for lungs

• layers - pleura

• pleural fluid (thin serous fluid to reduce friction)

parietal pleura

lines chest wall

visceral pleura

covers lungs

pericardial cavity (in mediastinum; ventral / thoracic cavity)

• heart

• layers - pericardium

• pericardial fluid

parietal pericardium

lines outer edge

visceral pericardium

covers heart surface

abdominal cavity (abdominopelvic)

• stomach, liver, intestines, spleen, pancreas, kidneys

• peritoneum

• peritoneal fluid (serous fluid)

parietal peritoneum

lines the wall

visceral peritoneum

covers abdominal organs

pelvic cavity (abdominopelvic)

• urinary bladder, reproductive organs, rectum

• layers -peritoneum

• small amounts of serous fluid/pelvic fluid

serous membranes

thin sheets of tissue to form double-layered structures filled with serous fluid to lubricate organs

homeostasis

condition in which body develops and maintains relatively stable internal environment

homeostatic imbalances

disturbances in homeostasis can lead to disease or death if uncorrected 

feedback loops

change in a regulated variable causes effects that feed back and in turn affect that same variable 

• Made up of a series of events that lead to an output

• As the loops continue, this output then influences the events of the loops themselves

negative feedback loops

oppose initial change and reduce output; goal is to decrease or remove stimulus – NOT ALWAYS BAD!!

steps for feedback loop:

1. Stimulus - information that regulated variable is outside normal range

2. Receptor or Sensor - cellular structure that registers stimulus

3. Control center - stimulus is sent to control center (brain or gland) by the nervous/endocrine system

4. Effector - cell or organ that will react 

5. Responses - effector causes response that will return variable to the normal range

EXAMPLE of: negative feedback loop

REGULATION OF BODY TEMP (HOT)

• Stimulus: increase of body temperature

• Receptor: thermoreceptors 

• Control center: brain (hypothalamus)

• Effector: sweat glands, blood vessels (which are dilating)

positive feedback loops

reinforce the initial change and increase the output; less common

EXAMPLE of: positive feedback loop

CHILDBIRTH

• Stimulus: contractions; uterine wall contracts

• Receptor: mechano receptors in uterine wall 

• Control center: hypothalamus (brain) will make more oxytocin 

• Effector: oxytocin and uterine wall = more contractions  

principle of complementarity of structure and function

structure determines function; applies to ALL levels of organization

matter

anything that has mass and occupies space

atom

smallest unit of matter that still retains its original properties

element

substance composed of one or more identical atoms; cannot be broken down into simple substances by chemical means

protons

positively charged particles that reside in the central core, or atomic nucleus, of the atom

neutrons

uncharged particles that are slightly larger than protons and also reside in the atomic nucleus

electrons

negatively charged tiny particles that surround the atomic nucleus

electron shells

discrete energy level where electrons orbit the nucleus of an atom

• similar to steps on a staircase

1st shell

• can hold 2 electrons

• closest to atomic nucleus

2nd shell

can hold 8 electrons

3rd shell

can hold 18 electrons, but is satisfied with 8

octet rule

an atom is most stable with 8 electrons in the valence shell

atomic number

number of protons found in the atomic nucleus

4 MAJOR ELEMENTS THAT MAKE UP 96% OF BODY’S MASS

• Oxygen (O) = 65%

• Carbon (C) = 18%

• Hydrogen (H) = 10%

• Nitrogen (N) = 3%

7 MINERAL ELEMENTS (less than 4%)

• sodium

• potassium

• calcium

• chlorine

• magnesium

• phosphorus

• sulfur

TRACE ELEMENTS

• Iron

• Zinc

• Copper

• Selenium

• Iodine

• Fluoride

mass number

sum of all protons and neutrons in atomic nucleus

isotope

atom with same number of protons, but different number of neutrons

molecule

formed by atoms CHEMICALLY bonded together

mixture

PHYSICAL combination of two or more separate substances that are NOT chemically bonded

solution (type of mixture)

liquid (usually water) mixed with a solid, liquid, or gas; one substance dissolves in another so appears translucent 

EXAMPLE: SALTWATER

colloids (type of mixture)

liquid mixed with solid; small particles are not visible so appears opaque; particles remain dispersed 

EXAMPLE: MILK

suspensions (type of mixture)

liquid mixed with solid; large solid particles are visible and will settle out of mixture

EXAMPLE: ITALIAN SALAD DRESSING

chemical bonds

an energy relationship, or attractive force, between atoms

molecule (type of chemical bond)

forms when 2 or more atoms of the same element are chemically bonded 

compound (chemical bonds)

forms when 2 or more atoms of different elements are chemically bonded

macromolecules (chemical bonds)

very large compounds composed of many atoms

valence electrons (chemical bonds)

chemical bonds form when valence electrons in the outermost shell, called the Valence shell, of atoms interact 

ionic bond

electrons are transferred between a metal atom and nonmetal atom

cation

POSITIVELY charged ion

anion

NEGATIVELY charged ion

how does an ionic bond form?

one atom completely transfers one or more valence electrons to another atom, creating oppositely charged ions that attract each other

covalent bonds

electrons are shared between two or more nonmetal atoms

NONpolar covalent bond

atoms share electrons equally because they have identical or very similar electronegativity values

POLAR covalent bond

atoms share electrons unequally because one atom is significantly more electronegative than the other

dipoles

polar molecules with partially positive and partially negative ends

how does electronegativity play a role in polar covalent bonds?

electronegativity determines how unequally electrons are shared between atoms in a covalent bond, creating the partial positive and partial negative charges

hydrogen bonds

weak attractions between partially positive atoms and partially negative atoms in polar molecules

EXAMPLE: WATER

energy

capacity to do work; energy can put matter into motion; fuels our chemical reactions 

potential energy

energy that is stored, ready to be released and used to do work

kinetic energy

energy in motion

how are energy forms interconvertible?

When energy changes form, some of it is usually converted into thermal energy (heat) due to friction or inefficiency, though the total amount of energy in the system remains constant

chemical energy

energy in chemical bonds; electrons are always in motion; drives cellular processes

electrical energy

generated by movement of charged ions

mechanical energy

energy directly transferred from one object to another

endergonic reactions

require one or more forms of energy from another source to proceed; products will contain more energy than reactants because energy was invested 

exergonic reactions

excess energy stored in the reactants during the reaction

catabolic reactions (exergonic)

larger substances are broken down into smaller ones

EXAMPLE: BREAKING DOWN FOOD

exchange reactions

transfer of atoms or electrons between reactants

EXAMPLE: CONVERTING ENERGY IN FOOD INTO A USABLE FORM

anabolic reactions (endergonic)

form new chemical bond

EXAMPLE: BUILDING NEW COMPOUNDS LIKE NEW TISSUES AND CELLS