BIO 100 Unit 1 / Chptr 1 Flashcards
append-
to hang something: appendicular—pertaining to the upper limbs and lower limbs.
cardi-
heart: pericardium—membrane that surrounds the heart.
cerebr-
brain: cerebrum—largest part of the brain.
cran-
helmet: cranial—pertaining to the part of the skull that surrounds the brain
dors-
back: dorsal—position toward the back of the body.
homeo-
same: homeostasis—maintenance of a stable internal environment.
-logy
-logy, the study of: physiology—study of body functions.
meta-
meta-, change: metabolism—chemical changes in the body.
nas-
nas-, nose: nasal—pertaining to the nose.
orb-
orb-, circle: orbital—pertaining to the portion of the skull that encircles an eye
pariet-
pariet-, wall: parietal membrane—membrane that lines the wall of a cavity.
pelv-
pelv-, basin: pelvic cavity—basin-shaped cavity enclosed by the pelvic bones.
peri-
peri-, around: pericardial membrane—membrane that surrounds the heart.
pleur-
pleur-, rib: pleural membrane—membrane that encloses the lungs within the rib cage.
-stasis
-stasis, standing still: homeostasis—maintenance of a stable internal environment.
super-
super-, above: superior—referring to a body part located above another.
-tomy
-tomy, cutting: anatomy—study of structure, which often involves cutting or removing body parts.
Two major areas of medical science,
anatomy and physiology - address how the body maintains life.
Anatomy
from the Greek for “a cutting up,” examines the structures, or morphology, of body parts—their forms and organization.
Physiology
from the Greek for “relationship to nature,” considers the functions of body parts—what they do and how they do it.
human organism
Body parts form a well-organized unit—the human organism.
atoms
All materials, including those that comprise the human body, are composed of chemicals. Chemicals consist of tiny particles called atoms, which are composed of even smaller subatomic particles. Atoms can join to form molecules, and small molecules may combine to form larger macromolecules.
cell
In humans and other organisms, the basic unit of structure and function is a cell.
organelles
Organelles are composed of assemblies of large molecules, including proteins, carbohydrates, lipids, and nucleic acids.
Specialized cells assemble into layers or masses that have specific functions.
Such a group of cells is called a tissue. Groups of different tissues form organs—complex structures with specialized functions—and groups of organs that function closely together comprise organ systems. Interacting organ systems make up an organism.
Subatomic particles - level of organization
levels of organization- Electrons, protons, neutrons
Atom - level of organization
levels of organization - Hydrogen atom, lithium atom
Molecule - level of organization
levels of organization -
Water molecule, glucose molecule
Macromolecule - level of organization
level of organization - Protein molecule, DNA molecule
Organelle - level of organization
level of organization - Mitochondrion, Golgi apparatus, nucleus
cell - level of organization
level of organization - Muscle cell, nerve cell
tissue - level of organization
level of organization - Simple squamous epithelium, bone
organ - level of organization
level of organization - Skin, femur, heart, kidney
organ system - level of organization
level of organization -
Integumentary system, skeletal system, digestive system
organism - level of organization
level of organization - human
The Cell
All living things on Earth consist of cells, from the single-celled bacteria and protozoans, to multicelled organisms like humans. Understanding anatomy and physiology is, in a way, understanding what conditions keep cells alive and well.
-Each cell is bounded by a cell membrane.
internal environment
is the environment within the body in which the cells live.
Homeostasis
is the maintenance of a relatively constant internal environment.
(Cells involved in reproduction do not have a direct role in maintaining homeostasis, but they have the special role of continuing the species.)
Interdependency of Cells
The fact that different cells contribute to homeostasis in different ways means that cells depend on one another. If some cells aren’t able to function, other cells and even the entire organism may suffer. One example is the loss of cells from the heart as a result of a heart attack. This places an additional workload on remaining heart cells. If the loss of functional cells is substantial, the organism may die.
Structure and Function
Structure and function are interrelated. An understanding of structure illuminates function, and vice versa.
Underlying Mechanisms and Processes—Foundations of Understanding
Cells form more-complex body structures such as tissues, organs, and organ systems, and all contribute to homeostasis through specific mechanisms. These mechanisms will repeat throughout this book, so once you learn them you will have a head start on upcoming chapters.
Gradients and Permeability
Substances move between cells and throughout the body in a number of ways. One way is movement from high to low, said to be down a gradient. In the case of blood flow, or air moving in and out of the lungs, the movement is down a pressure gradient, from high pressure to low pressure. Substances also move from areas of high concentration to areas of low concentration, down a concentration gradient, by a process called diffusion.
Cellular Differentiation (Gene Leads to Protein Leads to Function)
The wide range of cellular structures and the functions that cells perform throughout the body may be surprising considering that all of a person’s cells originate from a single fertilized egg. The cells become specialized by the process of cellular differentiation. Different cell types, such as muscle cells and nerve cells, access the information encoded in different genes to make specific proteins. The proteins that any cell makes determine that cell’s function.
Cell Membrane Mechanisms
The cell membrane determines which substances can enter a cell and which cannot. It also allows cells to respond to certain signals, but to ignore other signals.
Cell-to-Cell Communication
Cooperation among cells requires that they be able to communicate with each other. This occurs through a variety of mechanisms, many of which involve the cell membrane and specialized molecules on the membrane called membrane receptors.
Feedback Loops
For systems to maintain homeostasis, cells must signal other cells when the internal environment has been compromised so that adjustments can be made. When the instability has been corrected, cells must signal that the adjustments are no longer necessary. The mechanisms that accomplish these changes are called homeostatic mechanisms, and they work through a form of cell-to-cell communication called a feedback loop.
Balance
In order to maintain the internal environment relatively constant, the body must replace substances that are lost and eliminate substances that are in excess.
Energy Processes
All of the processes in the body involve some form of energy, whether heat energy, which keeps cells chemically active, or energy released from certain chemical reactions in a form that cells can use.
metabolism
the chemical processes that occur within a living organism in order to maintain life.
Water -
Human life depends on it: Requirements of Organisms
is the most abundant substance in the body. It is required for a variety of metabolic processes, and it provides the environment in which most of them take place. Water also carries substances in organisms and is important in regulating body temperature.
Food
Human life depends on it: Requirements of Organisms
refers to substances that provide organisms with necessary chemicals (nutrients) in addition to water. Nutrients supply energy and raw materials for building new living matter.
Oxygen
Human life depends on it: Requirements of Organisms
is a gas that makes up about one-fifth of the air. It is used to release energy from nutrients. The energy, in turn, is used to drive metabolic processes.
Heat
Human life depends on it: Requirements of Organisms
is a form of energy present in our environment. It is also a product of metabolic reactions and our body temperature depends in part on heat from the chemical reactions taking place in the body. Furthermore, the amount of heat present in the body partly controls the rate at which these reactions occur. Temperature is a measure of the amount of heat.
Pressure
Human life depends on it: Requirements of Organisms
is an application of force on an object or substance.
In humans, this pressure plays an important role in breathing. Similarly, organisms living under water are subjected to hydrostatic pressure—a pressure a liquid exerts—due to the weight of water above them. In complex animals, such as humans, heart action produces blood pressure (another form of hydrostatic pressure), which keeps blood flowing through blood vessels.
extracellular fluid
Extracellular fluid includes the liquid portion of the blood, the plasma, and the interstitial fluid, or tissue fluid, which is found outside of the blood vessels.
interstitial fluid
Interstitial fluid is in direct contact with cells throughout the body. All living cells contain water, along with substances dissolved in it, called intracellular fluid. Structures called cell membranes separate intracellular and extracellular fluids.
Receptors
They provide information about specific conditions (stimuli) in the internal environment. A receptor may be as small as a cell or even a protein that is part of a cell.
control center
decision-maker, that includes a set point, which is a particular value, such as body temperature at 37°C (Celsius) or 98.6°F (Fahrenheit)
Effectors
such as muscles or glands, take action. They cause appropriate responses.
negative feedback
In most homeostatic mechanisms, effectors are activated (or deactivated) such that conditions return toward normal. As this happens, the deviation from the set point progressively lessens, and the effector activity gradually returns to original levels. Such responses are said to operate by negative feedback (negative feedback loops), because the deviation from the set point is corrected (moves in the opposite, or negative, direction) and because the correction reduces the response of the effectors. This latter aspect is important because it prevents a correction from going too far.
positive feedback
In some cases, homeostatic mechanisms operate by positive feedback (positive feedback loops), in which a change is not reversed but intensified, and the effector activity is initially increased rather than turned off. An example is the distorted sound that occurs during a concert or a speech if the volume on the amplifier is too high
axial (ak′se-al) portion
which includes the head, neck, and trunk, and an appendicular (ap″en-dik′u-lar) portion
Within the axial portion are the cranial cavity
appendicular (ap″en-dik′u-lar) portion,
which includes the upper and lower limbs.
cranial cavity
which houses the brain; the vertebral canal
vertebral canal (spinal cavity)
which contains the spinal cord and is surrounded by sections of the backbone (vertebrae); the thoracic (tho-ras′ik) cavity; and the abdominopelvic (ab-dom′ĭ-no-pel′vik) cavity.
viscera
relating to the viscera.
“the visceral nervous system”
relating to deep inward feelings rather than to the intellect.
“the voters’ visceral fear of change”
thoracic
The thoracic cavity is separated from the abdominopelvic cavity by a broad, thin muscle called the diaphragm (di′ah-fram) When it is at rest, this muscle curves upward into the thorax like a dome. When it contracts during inhalation, it presses down upon the abdominal viscera. The wall of the thoracic cavity is composed of skin, skeletal muscles, and bones.
mediastinum
A compartment called the mediastinum (me″de-as-ti′num) extends forward to the sternum and backward to the vertebral column. It forms a boundary between the right and left sides of the thoracic cavity. The mediastinum contains most of the thoracic cavity viscera (including the heart, esophagus, trachea, and thymus) except for the lungs. The right and left lungs are on either side of the mediastinum.
abdominopelvic (ab-dom′ĭ-no-pel′vik) cavity.
The abdominopelvic cavity, which includes an upper abdominal portion and a lower pelvic portion, extends from the diaphragm to the floor of the pelvis. Its wall primarily consists of skin, skeletal muscles, and bones. The viscera within the abdominal cavity include the stomach, liver, spleen, gallbladder, kidneys, and the small and large intestines.
pelvic cavity
The pelvic cavity is the portion of the abdominopelvic cavity enclosed by the pelvic bones. It contains the terminal end of the large intestine, the urinary bladder, and the internal reproductive organs.
Smaller cavities within the head include the following:
Oral cavity, containing the teeth and tongue
Nasal cavity, connecting with several air-filled sinuses
Orbital cavities, containing the eyes and associated skeletal muscles and nerves
Middle ear cavities, containing the middle ear bones
serous membranes
line the walls of the thoracic and abdominopelvic cavities and fold back to cover the organs within these cavities. These membranes secrete a slippery serous fluid that separates the layer lining the wall of the cavity (parietal layer) from the layer covering an organ (visceral layer).
visceral pleural (ploo′ral) membranes
The space between the membranes (called the pleural cavity) is filled with a thin, lubricating liquid (called pleural fluid). The visceral pleura is the thin, slippery membrane that covers the surface of the lungs and dips into the areas separating the different lobes of the lungs (called the hilum ).
peritoneal (per″-ĭ-to-ne′al) membranes
A parietal peritoneum lines the wall of the abdominopelvic cavity, and a visceral peritoneum covers most of the organs in the abdominopelvic cavity. The potential space between these membranes is called the peritoneal cavity
integumentary (in-teg-u-men′tar-e) system
include the skin and accessory organs such as the hair, nails, sweat glands, and sebaceous glands. These parts protect underlying tissues, help regulate body temperature, house a variety of sensory receptors, and synthesize certain products.
skeletal (skel′eĕ-tal) system
consists of the bones as well as the ligaments and cartilages that bind bones together at joints. These parts provide frameworks and protective shields for softer tissues, serve as attachments for muscles, and act together with muscles when body parts move. Tissues within bones also produce blood cells and store inorganic salts.
muscular (mus′ku-lar) system
The muscles are the organs of the muscular (mus′ku-lar) system. By contracting and pulling their ends closer together, muscles provide the forces that move body parts. Muscles also help maintain posture and are the primary source of body heat.
