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What is 1 + 3?
Multiple sclerosis is caused by an autoimmune response that primarily affects the
All but which of the following are good barriers to invasion by microbes?
Which cells cause rapid division of other lymphocytes?
Antibodies belong to a group of compounds known as
Which immunoglobulin is the most common in secretions?
The same bacteria that are associated with periodontitis are associated with
Which system involves plasma proteins activated when they contact a bacterial cell?
Which cells produce and secrete antibodies that set up bacterial invaders for subsequent destruction by macrophages?
A motor neuron and all the muscles under its control are called what kind of unit?
Four of the five answers listed below are regions of the vertebral column. Select the exception.
The top (proximal end) of the femur joins to the
The most freely movable joints are the ____ joints.
The mineral stored in greatest quantity in bones is
Straps of dense connective tissue that join bones to bones are called
Straps of dense connective tissue that join muscles to bones are called
Toxins produced by this bacterium stop the release of acetylcholine, preventing normal muscle contraction.
Filtration occurs in which section of mammalian nephrons?
The transfer of heat by air or water is called
Which of the following substances is NOT filtered from the bloodstream?
How long after smoking marijuana can its breakdown product be detected in the urine?
What is the most abundant metabolic waste in urine produced by humans?
Toxic substances, such as ammonia and urea, which are routinely found in the blood, are metabolites of
The functional unit of the kidney is the
nephron tubules; peritubular capillaries
Reabsorption is the movement of water and solutes from the ____ to the ____.
both blood and interstitial fluid
Extracellular fluid is defined as
The greatest diversity of organisms in lake ecosystems is found in what zone?
A lake in which minerals are scarce is
The region where freshwater and saltwater mix is the
Eusocial vertebrates include
The communication signal requiring the most minimal distance between the sender and receiver animals is
bacteria and fungi
Wastes would accumulate and most nutrients would stop cycling if the ____ in the ecosystem died.
accumulation of toxic pollutants as animals pass through a food chain
Biological magnification refers to the
It requires huge amounts of energy and produces huge amounts of salt residues.
Desalinization may not be a good method for producing large amounts of freshwater because
amount of energy stored in the plant tissue in excess of that used by autotrophs in their respiration
Net primary productivity is the
A one-way relationship in which one species benefits at the expense of another is called
Which is an example of a habitat?
Most skin bacteria probably have what type of relationship with humans?
The organ of Corti is a
organ of corti
The place where vibrations are translated into patterns of nerve impulses is the
The highest concentration of cones is in the
The outer transparent protective cover of the eyeball is the
Increased pressure in the eye causes which of the following?
free nerve endings
Pain receptors are usually
hair cells are
Hormones are distributed throughout the body by the
The hormone that is antagonistic in action to glucagon is
metabolism and development
Thyroid hormone's main effect is on
What herbicide has been shown to be an endocrine disrupter?
Which gland enhances the immune function of T cells?
Excess glucose is converted into glycogen in the
The control over milk secretion, water balance, and labor in childbirth is mediated by the ____ gland.
The pacemaker for inhalation is located in the
Oxygen uptake by blood capillaries in fish gills occurs.
Blood and water flowing in opposite directions, in conjunction with respiratory systems, is a mechanism that explains how
Actual exchange of gases in the lungs occurs in the
releases oxygen more readily in highly active tissues
When you swallow, the epiglottis covers the opening to the
The movement of both oxygen and carbon dioxide in the body is accomplished by
An oxygen storage pigment that is abundant in muscle cells is
Four of the five answers listed below are related by the same function. Select the exception.
The continent with the highest potential for human population growth rate was ____ and that with the lowest was ____.
Density-independent controls over population growth include
low productive rate; large offspring
Organisms that demonstrate a type I survivorship curve are characterized by
all of these
the biotic potential
Which is not a density-dependent, growth-limiting factor?