Exam 3 Flashcards
1MM rule
Diffusion is an effective means of transporting substances only when the distance is < 1 MM
A______ Functions in both digestion and distribution of substances throughout the body
Gastrovascular cavity Note: some animals lack a circulatory system.
List 3 features of a circulatory system
circulatory fluid, set of interconnecting vessels, muscular pump(heart).
The circulatory system connects the fluid that surrounds cells with the organs that exchange_______ , _______ and _______
gases, absorb nutrients, and dispose of wastes
What type of circulatory system is this? The heart pumps the hemolymph through the vessels into interconnected sinuses, spaces around organs.
open circulatory system. Note: Any cell is within 2 cell thicknesses of Hemolymph
What type of circulatory system is this? The circulatory fluid is called blood.
Closed circulatory system
What type of circulatory system is this? Has a one chambered heart, one artery to gill capillaries, one artery to body capillaries and one vein back to the heart.
Single circulation: fish
What type of circulatory system is this? Has a two chambered atrium heart with a single ventricle chamber. Pulmocutaneous circuit, systemic circuit
Double circulation: amphibian
What type of circulatory system is this? Has two atrium and ventricle chambers of the heart. pulmonary circuit and a systemic circuit
Double circulation: Mammal
The __________ separate each atrium and ventricle
atrioventricular (AV) valves
The _________ control blood flow to the aorta and the pulmonary artery
semilunar valves
Backflow of blood through a defective valve causes a
heart murmur
The ________, or pacemaker, setsthe rate and timing at which cardiac musclecells contract
sinoatrial (SA) node
Some cardiac muscle cells are _______, meaning they contract without any signal fromthe nervous system
autorhythmic
Impulses that travel during the cardiac cyclecan be recorded as an________.
electrocardiogram(ECG or EKG)
The pacemaker is regulated by two portions ofthe nervous system: the ______ and _______ divisions.
sympathetic(speeds up) and parasympathetic (slows it down)
A vessel’s cavity is called the_____.
central lumen
The epithelial layer that lines blood vessels is called the ______.
endothelium( smooth & minimizes resistance)
Thin walls =
more gas exchange
Capillaries are only slightly _____ than a red blood cell
wider
Systolic pressure
High pressure
Diastolic pressure
low pressure
The recoil of elastic arterial walls plays a role in maintaining _____.
blood pressure
Precapillary sphincters
Can be shut off to redirect the flow to the main circulatory system.
The _____ returns fluid that leaksout from the capillary beds
lymphatic system. Note:The lymphatic system drains into veins in the neck
Fluid lost by capillaries is called
lymph
Blood composition. Plasma=__%, Cellular elements=__%.
Plasma=55%, Cellular elements45%.
____ , ____ and _______ all develop from a common source of stem cells
Erythrocytes, leukocytes, and platelets
Stem cells are in the red marrow of ______ , ______ , _____ , ______ and ______
bones, especially ribs, vertebrae, sternum and pelvis
The hormone _______ stimulates erythrocyte production when O2 delivery is low
erythropoietin (EPO)
_____ is the formation of a solid clot from liquid blood
Coagulation
A blood clot formed within a blood vessel is called a _____ and can block blood flow
thrombus
A cascade of complex reactions converts inactive _______ to ________, forming a clot
fibrinogen to fibrin
______ is the pressure exerted by a particular gas in a mixture of gases
Partial pressure
Gills are _______ of the body that create a large surface area for gas exchange
outfoldings
_________ moves the respiratory medium over the respiratory surface
Ventilation
The ________ of insects consists of a network of branching tubes throughout the body
tracheal system
The ______ directs air to the lungs and food tothe stomach
pharynx
Swallowing moves the ______ upward and tips the epiglottis over the glottis in the pharynx to prevent food from entering the ______
larynx, trachea
Air passes through the pharynx, larynx, trachea, ____, and ______ to the alveoli, where gas exchange occurs
bronchi, bronchioles
This “______” cleans the respiratory system and allows particles to be swallowed into the esophagus
mucus escalator
The process that ventilates the lungs is ____, the alternate inhalation and exhalation of air
breathing
______ pump air over the lungs at positive pressure
Amphibians
_____ use a bellows with both positive and negative parts
Birds
_____ use negative pressure in lungs
Mammals
_____, proteins that transport oxygen, greatly increase the amount of oxygen that blood can carry
Respiratory pigments
Arthropods and many molluscs have ______ with copper as the oxygen-binding component
hemocyanin
Most vertebrates and some invertebrates use ____
hemoglobin
In vertebrates, hemoglobin is contained within _____
erythrocytes
An organism’s ______ helps regulate the chemical composition of the body’s principal fluid.
excretory system
nitrogenous waste: Break down of proteins and nucleic acids produces ________
Ammonia (toxin)
Many aquatic organisms ____ ammonia, since it can be effectively diluted with water
excrete
Mammalian ____ convert ammonia into ____, which is much less toxic, and requires less water to excrete
livers, urea
Birds, reptiles, and some other organisms convert ammonia into ____, which is relatively nontoxic, and can be excreted as a _____ without much water loss
uric acid, semisolid
Types of excretory systems: protonephridia
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Types of excretory systems: Metanephridia
Picture
Types of excretory systems: Maiphigian tubules
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Key Functions of the Vertebrate excretory system
Filtration, reabsorption, secretion, Excretion.
Blood enters the kidneys via the ____ and leaves via the ___
renal arteries, renal veins
Urine is produced by the _____ and is conveyed to the ___ via the ureters
kidneys, urinary bladder
Each kidney processes about ____ of blood per day!
1000 L
Each kidney is divided into a ____ , ____ and ____
cortex, medulla, and pelvis
The functional units of the kidneys =
Nephrons
A nephron consists of: a ball of capillaries known as a ____
glomerulus
The glomerulus perfused by the_____
Afferent Arteriole
The Glomerulus is drained by the____
Efferent arteriole
Filtration occurs in _______ : cells and large molecules remain in the blood, while blood pressure forces water and small molecules from the blood into _____.
Bowman’s capsules
________ returns important nutrients (glucose, etc.) to the blood , and occurs especially in _____ and _____ tubules
Selective reabsorption, proximal and distal
_____ adds additional waste molecules to the filtrate, especially in the tubules
Selective secretion
How does the kidney selectively concentrate urine.
Counter curent distribution
Reabsorption of water occurs along the _____ , _____ , and_____.
tubules, descending loop of Henle, collecting duct.
_______ is the creation of an offspring by fusion of a male gamete (sperm) and female gamete (egg) to form a zygote
Sexual reproduction
_______ is creation of offspring without the fusion of egg and sperm
Asexual reproduction
Many invertebrates reproduce asexually by _____, separation of a parent into two or more individuals of about the same size
fission
Asexual: In ____, new individuals arise from outgrowths of existing ones
budding
Asexual: _____ is breaking of the body into pieces, some or all of which develop into adults
Fragmentation
Asexual: ______ is the development of a new individual from an unfertilized egg
Parthenogenesis
Why is sexual reproduction an evolutionary enigma?
Sexual females have half as many daughters as asexual females; this is the “twofold cost” of sexual reproduction
Name the 3 advantages of genetic recombination due to sexual reproduction.
- An increase in variation in offspring, providing an increase in the reproductive success of parents in changing environments
- An increase in the rate of adaptation
- A shuffling of genes and the elimination of harmful genes from a population
_____ is the release of mature eggs at the midpoint of a female cycle
Ovulation
Most animals exhibit reproductive cycles related to changing seasons
Fact:Reproductive cycles are controlled by hormones and/or environmental cues
One solution to no finding a sexual partner is ______ in which each individual has male and female reproductive systems
hermaphroditism,
The mechanisms of ______, the union of egg and sperm, play an important part in sexual reproduction
fertilization
In _________, eggs shed by the female are fertilized by sperm in the external environment
external fertilization
In ______, sperm are deposited in or near the female reproductive tract, and fertilization occurs within the tract
internal fertilization
All fertilization requires critical ____ , _____ , _____ and ______
timing, often mediated by environmental cues, pheromones, and/or courtship behavior
The embryos of some terrestrial animals develop in eggs with ______ and ______ shells and several internal membranes (adaptation to the terrestrial existence
calcium- and protein-containing
A _____ is a common opening between the external environment and the digestive, excretory, and reproductive systems present in nonmammalian vertebrates; mammals usually have a separate opening to the digestive tract
cloaca,
Ovaries act as both _______ and ________
reproductive organ and glands
Each ovary contains many ______, which consist of a partially developed egg, called an ____, surrounded by support cells
follicles, oocyte
______ expels an egg cell from the follicle, the cells of which produce estradiol prior to ovulation
Ovulation
The remaining follicular tissue grows within the ovary, forming a mass called the _____
corpus luteum
The _____ is a thin-walled chamber that is the repository for sperm during copulation and serves as the birth canal
vagina
The ________ are not part of the reproductive system but are important to mammalian reproduction
mammary glands
During _______, sperm are propelled through the muscular vas deferens and the ejaculatory duct, and then exit the penis through the urethra
ejaculation
_____ is composed of sperm plus secretions from three sets of accessory glands
Semen
The two seminal vesicles contribute about __% of the total volume of semen
60%
The ______ secrete a clear mucus before ejaculation that neutralizes acidic urine remaining in the urethra
bulbourethral glands
Thickening of the endometrium during the _______ coordinates with the follicular phase
proliferative phase
Shedding of the endometrium during the ________ coordinates with the growth of new ovarian follicles
menstrual flow phase
After about 500 cycles, human females undergo ______, the cessation of ovulation and menstruation
menopause
Menstrual cycles are characteristic only of ____and some other ______
humans , primates
______, fertilization of an egg by a sperm, occurs in the oviduct
Conception
Division of cells gives rise to a______, a ball of cells with a central cavity
blastocyst: After blastocyst formation, the embryo implants into the endometrium
After the embryo implants into the endometrium, the embryo releases , which prevents menstruation
human chorionic gonadotropin (hCG); Fact: basis of pregnancies test
Splitting of the embryo during the first month of development results in genetically ______
identical twins
_____ are nerve cells that transfer information within the body
Neurons
Neurons use two types of signals to communicate: ______ and ______
electrical signals (long-distance) and chemical signals (short-distance)
Processing of information takes place in simple clusters of neurons called ____ or a more complex organization of neurons called a ____
ganglia , Brain
Most neurons have _____, highly branched extensions that receive signals from other neurons
dendrites
The _____ is typically a much longer extension that transmits signals to other cells at synapses
axon
The synaptic terminal of one axon passes information across the synapse in the form of chemical messengers called _______
neurotransmitters
A ______ is a junction between an axon and another cell
synapse
Most neurons are nourished or insulated by cells called ____
glia or glial cells
Nervous systems process information in three stages: ___ , ___ and ___
sensory input, integration, and motor output
A _______ where integration takes place; this includes the brain and a nerve cord
central nervous system (CNS)
A _______, which carries information into and out of the CNS
peripheral nervous system (PNS)
The neurons of the PNS, when bundled together, form ____
nerves
If a depolarization shifts the membrane potential sufficiently, it results in a massive change in membrane voltage called an_____
action potential
During the ______ after an action potential, a second action potential cannot be initiated
refractory period
In vertebrates, axons are insulated by a _____ , which causes an action potential’s speed to increase
myelin sheath
The speed of an action potential increases with the axon’s ____
diameter
The presynaptic neuron synthesizes and packages the neurotransmitter in _____ located in the synaptic terminal
synaptic vesicles
The neurotransmitter diffuses across the ______ and is received by the postsynaptic cell
synaptic cleft
_______________ are depolarizations that bring the membrane potential toward threshold
Excitatory postsynaptic potentials (EPSPs)
________________are hyperpolarizations that move the membrane potential farther from threshold
Inhibitory postsynaptic potentials (IPSPs)
____ is the biological form of an organism
anatomy
____ is the biological form of an organism
physiology
_________ the genome, itself the product of millions of years of evolution
The Body plan of an animal is programmed by
Convergent evolution often results in similar adaptations of diverse organisms when ___
Facing the same challenge
What materails must cells exchange across its membranes
Nutrients, waste products, gases
Rate of exchange is proportional to
a Cell’s surface area
What evolutoinary adaptations enable sufficient exchange with the environment?
Specialized, extensively branched or folded structures
Internal control mechanism to control internal change in the face of external fluctuation
a regulator
Allows it’s internal condition to vary with certain external changes
A conformer
The tendency toward a relatively stable equilibrium between interdependent elements, especailly as maintainced by physiological processes
homeostasis
Organisms use this to maintain a “steady state” or internal balance regardless of external environment
homeostasis
For a given variable, fluctuations above or below a _____ serve as a______; these are detected by a ______ and triggers a_______
set point, Stimulus, sensor, response
Homestatsis in animals relies largely on what kind of control
Negitive feedback
_______ feedbackamplifies a stimulus. It either associated with pathological conditions or a change or state.
Positive feedback
In animals and plants a ________ governs physiological changes that occur roughly every 24 hours.
circadian rhythm
Homeostasis can adjust to changes in external environments, a process called
Acclimatization
Animals generate heat by metabolism; birds and mammals.
Endothermic
Animals gain heat from external sources; includes most invertebrates, fishes, amphibians, and nonavian reptiles
ectothermic
____ can maintain a stable body temperature even in the face of large fluctutations in environmental temperature
Endotherms
In general, ___ tolerate greater variation in internal temperature
Ectotherms
_____ is more energetically expensice than the other.
Endothermy
The body temperature of a poikilotherm varies___________
with its environment
The relationship between heat source and body temperature is not fixed (that is, not all poikilotherms are
ectotherms
Both endotherms and ectotherms use___________ to control body temperature
Behavioral responses
Honey beese huddled together during cold weather to retain heat is a
behavioral response
Thermoregulation in mammals is controlled by a region of the brain called
the Hypothalamus
The _______ triggers heat loss or heat generating mechnisms
the Hypothalamus
_____, a response to some infections, reflects an increase in the normal range for the biological thermostat
Fever
Some_______ organisms seek warmer environments to increase theirbody temperature in response to certain infections
Ectothermic
_____ is the overall flow and transformation of energy in an animal
Bioenergetics
it dertermins how much food an aniaml needs and it relates to an animals size, activity and environment
Bioenergetics
_____ is the metabolic rate of an endotherm at rest at a “comfortable” temperature
Basal metabolic rate
_______ is the metabolic rate of an ectotherm at rest at a specific temperature
standard metabolic rate
Ectotherms have a ______metablic rates than endotherms of a comparable size
much lower
