EXAM 5 Flashcards
The study of the relationships of organisms with one another (biotic) and with their non-living environment (abiotic) is ________.
Ecology
The goal of ecology is to explain why certain organisms are ________________________________. (____________ and ____________)
The goal of ecology is to explain why certain organisms are found where they are. (Distribution and abundance)
What are the 2 ways of studying ecology?
descriptive and dynamic
Levels of Organization in Ecology:
- S_____
- P_________
- C__________
- E_________
- B_____
- B________
Basic level to start studying Ecology: _________
Levels of Organization in Ecology:
- Species
- Population
- Communities
- Ecosystems
- Biomes
- Biosphere
Biosphere Basic level to start studying Ecology: population
a group of individuals of a given species that live in the same area at the same time
population
Characteristics of a Population:
– S___ (________)
– D______
– G_____
– R___
Characteristics of a Population:
– Size (descriptive)
– Density
– Growth
– Role
Population Size has a ______ influence on survival:
►_____ population = good survival possibilities
►_____ population = not good, due to
- Natural ________, and
- Genetic problems, such as:
_______
lowered _____
lack of _________
Population Size has a direct influence on survival:
►Large population = good survival possibilities
►Small population = not good, due to:
- Natural disasters
- Genetic problems, such as:
inbreeding
lowered vigor
lack of variability
Population Density:
(How _____ or ___ apart are organisms found)
Has a related ___________ or dispersion:
– ________ (aggregated): elephants herd, school of fish
– _______ (Regular or Even): desert bushes
– _____
Population Density:
(How close or far apart are organisms found)
Has a related distribution or dispersion:
– Clumped (aggregated): elephants herd, school of fish
– Uniform (Regular or Even): desert bushes
– Random
maximum rate at which population can increase in optimal conditions
Biotic Potential
limits set by the living and non-living environments (availability of food, space, competition, interactions, natural events)
environmental resistance
All populations show growth as a result of a relation between ______ _________ and ____________ __________.
All populations show growth as a result of a relation between biotic potential and environmental resistance.
____________ growth occurs when a population continuously grows at a _____ __________ of its size at the beginning of each time period,
which results in a __-_______ growth curve.
Exponential growth occurs when a population continuously grows at a fixed percentage of its size at the beginning of each time period,
which results in a J- shaped growth curve.
__________ ____ describes the amount of time it takes to double its population at its current state of growth and can be calculated as __/__ (r = growth rate).
Doubling time describes the amount of time it takes to double its population at its current state of growth and can be calculated as .7/r (r = growth rate).
Biotic potential (max growth in optimal conditions) is influenced by:
(1) Age at which the organism first __________
(2) Reproduction _________
(3) Average _________
(4) Length of the organism’s ___________ ____ ____
(5) _____ rate
Biotic potential (max growth in optimal conditions) is influenced by:
(1) Age at which the organism first reproduces
(2) Reproduction frequency
(3) Average offspring
(4) Length of the organism’s reproductive life span
(5) Death rate
Populations use what two main strategies to control population size?
K-strategist
&
r-strategist
K- strategist:
– Limited by _______ ________ of environment
– Generally show _________ growth curve
– Tend to live in fairly ______ habitats, _________ late, few _________ (_____ size, ______ slowly, receive intensive ________ ____, generations relatively ____)
– i.e. whales, rhinoceros, coconut palms, whooping cranes
K- strategist:
– Limited by carrying capacity of environment
– Generally show sigmoidal growth curve
– Tend to live in fairly stable habitats, reproduce late, few offspring (large size, mature slowly, receive intensive parental care, generations relatively long)
– i.e. whales, rhinoceros, coconut palms, whooping cranes
r – strategist:
– ________ rate of growth is most important
– Tend to live in ________ environments
– Reproduce _____, have ____ offspring
– Offspring are _____ & mature ____,
without _______ ___
– Generations are relatively _____
– i.e. bacteria, annual plants, protozoa, earthworm
r – strategist:
– Intrinsic rate of growth is most important
– Tend to live in unstable environments
– Reproduce early, have many offspring
– Offspring are small & mature fast,
without parental care
– Generations are relatively short
– i.e. bacteria, annual plants, protozoa, earthworm
Exponential growth either _______ _________ or _______.
Exponential growth either reaches stability or crashes.
Exponential growth can be caused by:
temporary increase of ____ _____,
introduction of ______ _______,
reduction of _________,
or protection of _______.
Exponential growth can be caused by:
temporary increase of food supply,
introduction of exotic species,
reduction of predators,
or protection of species.
________ _____ occurs when populations ________ to the _______ number sustainable by their environment or ________ ________ (K), without damage to the ecosystem and results in an __-______ growth curve.
Logistic growth occurs when populations increase to the maximum number sustainable by their environment or carrying capacity (K), without damage to the ecosystem and results in an s-shaped growth curve.
Consequences of Exceeding K (carrying capacity):
⇒ Damage to _________
⇒ Further _________ __
⇒_________ or ___________ of population
Consequences of Exceeding K (carrying capacity):
⇒ Damage to resources
⇒ Further decreased K
⇒ Reduction or elimination of population
Environmental resistance can be classified into two broad categories
_______-___________ factors
_______-_________ factors
Environmental resistance can be classified into two broad categories
Density-independent factors
Density-dependent factors
_______-__________ factors limit
populations regardless of their density.
Examples:
c_____, w_____, p________, p________, o_________
Density-independent factors limit
populations regardless of their density.
Examples:
climate, weather, pesticides, pollutants, overhunting
Density-________ factors:
become ____ effective as population density _______,
exert ______ feedback effect on population size
(birth rate ____, death rate ________, __-curve results),
and include community interactions such as p________, p________, and c__________.
Density-dependent factors:
become more effective as population density increases,
exert negative feedback effect on population size (birth rate drops, death rate increases, s-curve results),
and include community interactions such as predation, parasitism, and competition.
Predator-prey affect each other in cycles:
Availability of ____
⇒ ________ predators
⇒ ________ prey
⇒________ predators
Predator-prey affect each other in cycles:
Availability of prey
⇒ increase predators
⇒ decrease prey
⇒decrease predators
Parasitism involves a ________ living on or in a ____ ________, _______ on it and _________ it but generally not _______ it.
Examples: ________ causing Lyme disease,
some _____, intestinal _____, _____, and some ______
Parasitism involves a parasite living on or in a host organism, feeding on it and weakening it but generally not killing it.
Examples: bacterium causing Lyme disease,
some fungi, intestinal worms, ticks, and some protists
describes the interaction among individuals who attempt to utilize a that is limited relative to the for it, and ________ as populations grow near carrying capacity.
Competition describes the interaction among individuals who attempt to utilize a shared resource that is limited relative to the demand for it, and intensifies as populations grow near carrying capacity.
may be divided into two groups:
is between individuals of different species
is between individuals of the same species
Competition may be divided into two groups:
Interspecific competition is between individuals of different species
Intraspecific competition is between individuals of the same species
The size of a population at any given time is the result of complex interactions between _________ and _________ _________.
The size of a population at any given time is the result of complex interactions between interspecific and intraspecific competition.
____________ __ ____________ describes the pattern of survival in a population
____ ______ track groups of organisms born at the same time throughout their life span and can generate ____________ _________.
Survivorship in Populations describes the pattern of survival in a population
Life tables track groups of organisms born at the same time throughout their life span and can generate Survivorship Curves.
What three types of survivorship curves can be distinguished?
late loss
constant loss
early loss
____ loss curves are seen in many animals with ___ _________ that receive substantial ________ ____.
examples: ______ and many large _______
Late loss curves are seen in many animals with few offspring that receive substantial parental care.
examples: humans and many large mammals
________ ____ curves are an approximate straight line, indicating an equal chance of ________________.
example: some _____ species
Constant loss curves are an approximate straight line, indicating an equal chance of dying at any age
example: some bird species
_____ ____ ______show high early mortality as ____ _________ fail to become established.
examples: most ___________ and ____
Early loss curves show high early mortality as most offspring fail to become established.
examples: most invertebrates and fish
Change in Human Populations
Human Population Continues to ____ _______
Technological Advances Have Increased Earth’s _______ ________
Demographic __________ Helps _______ Populations
Population Growth Is ________ Distributed
The ______ ___ ________ of a Population Predicts Its ______ ______
Fertility in Europe Is _____ ___________ Level
The United States Populations Is _______ _______
Change in Human Populations
Human Population Continues to Grow Rapidly
Technological Advances Have Increased Earth’s Carrying Capacity
Demographic Transition Helps Stabilize Populations
Population Growth Is Unevenly Distributed
The Current Age Structure of a Population Predicts Its Future Growth
Fertility in Europe Is Below Replacement Level
The United States Populations Is Growing Rapidly
the branch of science that studies the changing human population
demography
Demographers track _________ _______ in different _________ and _______.
Demographers track population changes in different countries and regions.
___________ ____ are used to _________ ________ in public health, housing, education, employment, immigration, and environmental protection.
Demographic data are used to formulate policies in public health, housing, education, employment, immigration, and environmental protection.
Over the ____ ______, the rate of human population growth seems to be ________, with 75-80 million people added per year, indicating that we may be entering the _____ ____ of the _______.
Over the last decade, the rate of human population growth seems to be stabilizing, with 75-80 million people added per year, indicating that we may be entering the final bend of the s-curve.
Several technological ___________ have greatly influenced the human ability to make _______ available:
_______ & _______
_______
_______-_______
Several technological revolutions have greatly influenced the human ability to make resources available:
technical & cultural
agricultural
industrial-medical
_______ & _____ revolution occurred in ______ humans.
The invention of ______ and _______ increased food availability, and the discovery of _____ and creation of _____ and _____ increased their _____ _____.
Technical & cultural revolution occurred in primitive humans.
The invention of tools and weapons increased food availability, and the discovery of fire and creation of shelters and clothing increased their habitable range.
Agricultural revolution occurred beginning c. _______ when ________ and ______ were domesticated.
Agricultural revolution occurred beginning c. 8000 B.C. when animals and plants were domesticated.
The ________-_______ revolution occurred beginning ___-_____ century.
It allowed _____ people to produce _____ food and _____ the death rate from ________ ________.
This resulted in an _____ ___ in population, which then stabilized due to a later _____ in _____ _____.
The industrial-medical revolution occurred beginning mid-18th century.
It allowed fewer people to produce more food and decreased the death rate from infectious disease.
This resulted in an initial rise in population, which then stabilized due to a later decrease in birth rates.
a change in population that results from an initial decrease in death rate followed by a decrease in birth rates
demographic transition
Declining birth rates associated with demographic transition result from many factors:
better ________
increased access to ________
shift of populations to ________
more ________ working ________ the home
Declining birth rates associated with demographic transition result from many factors:
better education
increased access to contraceptives
shift of populations to cities
more women working outside the home
When the adults of a population have just enough children to replace themselves, the situation is called __________-____ ______ (___).
Because not all children _______ to _____, ___ is slightly higher than __.
When the adults of a population have just enough children to replace themselves, the situation is called replacement-level fertility (RLF).
Because not all children survive to maturity, RLF is slightly higher than 2.
Many developing countries still have _______ _______ populations:
– birth rates _______ _______ death rates
– Children aid in _______ _______
– Limited access to _______
– Even if dropped to RFL, countries like China
will continue growing due to ______ of ______ ______.
Many developing countries still have rapidly growing populations:
– birth rates vastly exceed death rates
– Children aid in family income
– Limited access to contraception
– Even if dropped to RFL, countries like China
will continue growing due to amount of young people.
Population Age Structure:
– ________ according to age groups
– The shape below the peak reveals if the population is ______, ______, or ______
Population Age Structure:
– Distribution according to age groups
– The shape below the peak reveals if the population is expanding, stable, or shrinking
In an age structure that is pyramid-shaped, the population is _________ and _____ RLF.
example: ______
In an age structure that is pyramid-shaped, the population is expanding and above RLF.
example: Mexico
In an age structure that has relatively straight or _________ sides, the population is _____ and __ RLF.
example: _______
In an age structure that has relatively straight or symmetrical sides, the population is stable and at RLF.
example: Sweden
In an age structure that has a narrow base, the population is ______ and _____ RLF.
example: _____
In an age structure that has a narrow base, the population is shrinking and below RLF.
example: Italy
Even if developing countries were to achieve RLF ___________, their population increases would continue for _______.
Even if developing countries were to achieve RLF immediately, their population increases would continue for decades.
U.S. population is fastest growing of all industrial nations:
U.S. fertility rate is only approx. ___, _____ RLF
However, ________ is adding people rapidly and ________ remains higher than in other nations
U.S. population is fastest growing of all industrial nations:
U.S. fertility rate is only approx. 2.0, below RLF
However, immigration is adding people rapidly and survivorship remains higher than in other nations
Growth of the U.S. has serious implications for the environment of the U.S. and the Earth:
Americans consume ___ ____ ______ and produce ___ ____ ________ than the global average
The ________ ________ is more than ___ times greater for U.S. residents than the global average
Growth of the U.S. has serious implications for the environment of the U.S. and the Earth:
Americans consume far more resources and produce far more pollution than the global average
The ecological footprint is more than 2.5 times greater for U.S. residents than the global average
_______ (nerve cells) must perform four specialized functions:
– _______ information
– _______ information
– _______ _______ over distances
– _______ _______ to other neurons, tissues, or organs
Neurons (nerve cells) must perform four specialized functions:
– Receive information
– Integrate information
– Conduct signals over distances
– Transmit signals to other neurons, tissues, or organs
Typical neurons have four distinct structural regions
_______
_______
_______
_______
Typical neurons have four distinct structural regions
- *dendrites**
- *cell** body
- *axon**
- *synaptic** terminals
_______ are branched cell body extensions that _______ _______ from surrounding neurons and sensory receptors.
Dendrites are branched cell body extensions that receive information from surrounding neurons and sensory receptors.
The cell body _______ incoming information from _______; if incoming signals are _______ enough, an _______ _______ (electrical output signal) forms.
The cell body integrates incoming information from dendrites; if incoming signals are positive enough, an action potential (electrical output signal) forms.
The ____ conducts electrical signals to the _______ _______, is often covered in _______ to speed electric transmission, and is often _______ _______ to form nerves.
The axon conducts electrical signals to the synaptic terminal, is often covered in myelin to speed electric transmission, and is often bundled together to form nerves.
The ______ ______ is the branched endings of axons.
Most contain _______________, specific chemicals released under the stimulus of an action potential.
Forms _______ with other cells - the site at which the neuron communicates with other _____, _______, or _______.
The synaptic terminal is the branched endings of axons.
Most contain neurotransmitters, specific chemicals released under the stimulus of an action potential.
Forms synapses with other cells - the site at which the neuron communicates with other cells, tissues, or organs.
Neural activity occurs when _______ produce _______ _______ across their _______.
Neural activity occurs when neurons produce electrical voltages across their membranes.
Most neurons have a negative resting potential:
– Describes the resting ______ ______ ______
– Ranges from ___ to ___ millivolts (mV)
– Negative value indicates that the ____ ______ is more negative than the ______
Most neurons have a negative resting potential:
– Describes the resting neuron membrane potential
– Ranges from -40 to -90 millivolts (mV)
– Negative value indicates that the cell interior is more negative than the exterior
If the neuron membrane potential becomes less negative, reaching a ______ ______, the neuron will generate an ______ ______.
If the neuron membrane potential becomes less negative, reaching a threshold value, the neuron will generate an action potential.
______ ______ is when the neuron membrane potential rises rapidly to +50 mV, then returns to ______ ______.
The action potential signal flows down ____ to ______ ______, where cell communication occurs.
Action potential is when the neuron membrane potential rises rapidly to +50 mV, then returns to resting potential.
The action potential signal flows down axons to synaptic terminals, where cell communication occurs.
Neurons communicate at _______.
- The _______ neuron transmits a signal by releasing _____________ molecules from _______ into the _______ gap.
- The _______ neuron has specialized _______ molecules which bind to the _____________ and cause _______ in the cell.
Neurons communicate at synapses.
- The presynaptic neuron transmits a signal by releasing neurotransmitter molecules from vesicles into the synaptic gap.
- The postsynaptic neuron has specialized receptor molecules which bind to the neurotransmitter and cause changes in the cell.
When ________ neuron receptors bind to neurotransmitters, specific ____ ______ open and allow ion flow across the cell membrane, which causes a brief change in membrane potential (________ ________, or ____).
When postsynaptic neuron receptors bind to neurotransmitters, specific ion channels open and allow ion flow across the cell membrane, which causes a brief change in membrane potential (postsynaptic potential, or PSP).
________ postsynaptic potentials (EPSPs)
–Make the neuron ____ negative inside
–The membrane potential gets ______ ____ threshold potential
–And is ____ likely to form an action potential
– Can occur when ___ ______ open,
allowing ___ into the cell
Excitatory postsynaptic potentials (EPSPs)
– Make the neuron less negative inside
– The membrane potential gets closer to threshold potential
– And is more likely to form an action potential
– Can occur when Na+ channels open,
allowing Na+ into the cell
________ postsynaptic potentials (IPSPs)
—Make the neuron ____ negative inside
—The membrane potential gets ______ ______
threshold potential
—And is ____ likely to form an action potential
—Can occur when ___ _______ open,
allowing ___ ____ of the cell
Inhibitory postsynaptic potentials (IPSPs)
—Make the neuron more negative inside
—The membrane potential gets further from
threshold potential
—And is less likely to form an action potential
—Can occur when K+ channels open,
allowing K+ out of the cell
Individually, PSPs are weak
and cannot stimulate an _____ _______.
_______ & a ____ ____ receive many EPSPs and IPSPs.
_______ of PSPs occurs – if threshold is reached, an
_______ _______ forms.
Individually, PSPs are weak
and cannot stimulate an action potential.
Dendrites & a cell body receive many EPSPs and IPSPs.
Summation of PSPs occurs – if threshold is reached, an
action potential forms.
Information processing requires four basic operations:
_______ ____ of stimulus
_______ _______ of stimulus
_______ information (_______)
_______ the response (_______)
Information processing requires four basic operations:
Determine type of stimulus
Signal intensity of stimulus
Integrate information (convergence)
Direct the response (divergence)
Nervous systems determine the type of stimulus based on ______ ______ in the brain - ______ parts of the brain perceive _______ _______ when stimulated.
Nervous systems determine the type of stimulus based on wiring patterns in the brain - specific parts of the brain perceive specific senses when stimulated.
Stimulus intensity is coded by the frequency of _____ _______ and the _____ of _____ that are involved.
Stimulus intensity is coded by the frequency of action potentials and the number of neurons that are involved.
Neurons _______ information from many sources and process through _______:
_____ neurons funnel their signals to _____ neurons,
_______ occurs in these neurons and appropriate _______ are formed.
Neurons integrate information from many sources and process through convergence:
many neurons funnel their signals to fewer neurons,
summation occurs in these neurons and appropriate responses are formed.
Neurons initiate and direct complex responses via _______:
a few ______-______ neurons stimulate _____ neurons that control _______ and _______.
Neurons initiate and direct complex responses via divergence:
a few decision-making neurons stimulate many neurons that control muscles and glands.
Most neural pathways contain four elements:
– _______ neurons
– _______ neurons
– _______ neutrons
– _______
Most neural pathways contain four elements:
– Sensory neurons
– Association neurons
– Motor neutrons
– Effectors
______ ______ receive information from the internal or external environment.
Sensory neurons receive information from the internal or external environment.
__________ _______ integrate information from many different sources and activate motor neurons.
Association neurons integrate information from many different sources and activate motor neurons.
_____ ______ receive instructions from association neurons and activate muscles or glands.
Motor neurons receive instructions from association neurons and activate muscles or glands.
_______ are muscles or glands that perform the desired response.
Effectors are muscles or glands that perform the desired response.
_____: an involuntary movement of a body part in response to a stimulus; most follow _______ neural pathways.
Reflex: an involuntary movement of a body part in response to a stimulus; most follow standard neural pathways.
Radially symmetric animals have a ______ ___ (a diffuse network of neurons that interconnect ganglia) and lack a _______.
Radially symmetric animals have a nerve net (a diffuse network of neurons that interconnect ganglia) and lack a brain.
Bilaterally symmetric animals have a _______ nervous system; _____ ________ tend to be clustered in the ____ ______ (cephalization) and along the ______ ____.
Bilaterally symmetric animals have a centralized nervous system; cell bodies tend to be clustered in the head region (cephalization) and along the central axis.
The nervous system of _______ animals is divided into two parts:
the ______ Nervous System (______ & ______ _____)
the _______ Nervous System (nerves that _______ the CNS to the ______________)
The nervous system of bilateral animals is divided into two parts:
the Central Nervous System (brain & spinal cord)
the Peripheral Nervous System (nerves that connect the CNS to the rest of the body)
The PNS consists of peripheral nerves:
_____ and _____ neurons.
The PNS consists of peripheral nerves:
motor and sensory neurons.
The motor portion of the ____ is divided into two parts:
the _______ nervous system controls _______ motion,
the _______ nervous system controls _______ responses.
The motor portion of the PNS is divided into two parts:
the somatic nervous system controls voluntary motion,
the autonomic nervous system controls involuntary responses.
The autonomic nervous system has two divisions:
the _______ division prepares the body for fight or flight,
the __________ division dominates during rest and rumination.
The autonomic nervous system has two divisions:
the sympathetic division prepares the body for fight or flight,
the parasympathetic division dominates during rest and rumination.
The CNS is protected in three ways:
the _____ and _______ _______
the _______
the _____-_____ _______
The CNS is protected in three ways:
the skull and vertebral column
the meninges
the blood-brain barrier
CNS Protection:
The skull and vertebral column: ____ _____
The meninges: a triple layer of ______ tissue with _________ fluid for cushioning
The blood-brain barrier: relatively impermeable ______ ___________ that prevent _______ and damaging ______ from entering the brain
CNS Protection:
The skull and vertebral column: bony armor
The meninges: a triple layer of connective tissue with cerebrospinal fluid for cushioning
The blood-brain barrier: relatively impermeable brain capillaries that prevent microbes and damaging chemicals from entering the brain
The spinal cord is a cable of ____ protected by the _______ that transmits signals between the brain and body and is composed of ____ _____ & ____ _____.
The spinal cord is a cable of axons protected by the backbone that transmits signals between the brain and body and is composed of grey matter & white matter.
_____ matter consists mostly of cell bodies of motor and association neurons.
Grey matter consists mostly of cell bodies of motor and association neurons.
_____ matter surrounds the ____ matter and consists mostly of myelinated ____ that send impulses up and down the spinal cord.
White matter surrounds the grey matter and consists mostly of myelinated axons that send impulses up and down the spinal cord.
The ______ ____ also contains neural pathways for some simple behaviors, such as _________.
The spinal cord also contains neural pathways for some simple behaviors, such as reflexes.
All ______ brains develop anatomical and functional divisions: ______, ______, ______.
All vertebrate brains develop anatomical and functional divisions: hindbrain, midbrain, forebrain.
The hindbrain includes the _______, ____, and ________.
The hindbrain includes the medulla, pons, and cerebellum.
The ______ (hindbrain) controls several autonomic functions, such as breathing, heart rate, and blood pressure.
The medulla (hindbrain) controls several autonomic functions, such as breathing, heart rate, and blood pressure.
The ____ (hindbrain) plays a role in the transition from sleep to wakefulness, and regulates breathing rate.
The pons (hindbrain) plays a role in the transition from sleep to wakefulness, and regulates breathing rate.
The _________ (hindbrain) helps coordinate movements of the body.
The cerebellum (hindbrain) helps coordinate movements of the body.
The midbrain contains the _______ _______, an important _____ and _____ filtering station that extends from the ______ into the lower regions of the ______.
The midbrain contains the reticular formation, an important relay and sensory filtering station that extends from the medulla into the lower regions of the forebrain.
The forebrain includes the _____, _____ _____, and _____ _____.
The forebrain includes the thalamus, limbic system, and cerebral cortex.
The _______ (forebrain) channels sensory information from all parts of the body to the _______ system and _______ cortex.
The thalamus (forebrain) channels sensory information from all parts of the body to the limbic system and cerebral cortex.
The ______ ______ (in the forebrain) is a group of structures that produce our most basic and primitive ______, ______, and ______.
The limbic system (in the forebrain) is a group of structures that produce our most basic and primitive emotions, drives, and behaviors.
The limbic system is composed of the _______, _______, and _______.
The limbic system is composed of the hypothalamus, amygdala, and hippocampus.
The _________ is a coordinating center between the nervous and endocrine systems.
The hypothalamus is a coordinating center between the nervous and endocrine systems.
The _______ produces sensations of pleasure, fear, or sexual arousal.
The amygdala produces sensations of pleasure, fear, or sexual arousal.
The _________ is involved in emotional behaviors and the formation of long-term memory.
The hippocampus is involved in emotional behaviors and the formation of long-term memory.
The ______ ______ is the convoluted outer layer of the forebrain that is divided into two hemispheres connected by a large band of axons called the ______ ______.
The cerebral cortex is the convoluted outer layer of the forebrain that is divided into two hemispheres connected by a large band of axons called the corpus callosum.
Each cerebral cortex hemisphere is divided into four anatomical regions:
______ lobe
______ lobe
______ lobe
______ lobe
Each cerebral cortex hemisphere is divided into four anatomical regions:
frontal lobe
parietal lobe
occipital lobe
temporal lobe
Each cerebral cortex hemisphere is made of different functional areas:
–______ ______ ______: where sensory signals are received, impressions are formed
–______ ______: interpret sounds and link sensory stimuli with memories
–______ ______ ______: in the frontal lobe; stimulate motor neurons
Each cerebral cortex hemisphere is made of different functional areas:
–Primary sensory areas: where sensory signals are received, impressions are formed
–Association areas: interpret sounds and link sensory stimuli with memories
–Primary motor areas: in the frontal lobe; stimulate motor neurons
The left hemisphere dominates
the following brain functions:
s______
r______
w______
l______ c______
m______ a______
l______ p______ s______
The left hemisphere dominates
the following brain functions:
speech
reading
writing
language comprehension
mathematical ability
logical problem solving
The right hemisphere dominates
the following brain functions:
f_______ r_______
s_______ r_______
a_______ & m_______ a_______
r_______ & e_______ of e_______
The right hemisphere dominates
the following brain functions:
facial recognition
spatial relationships
artistic & musical ability
recognition & expression of emotion
_____ within each ____ ____ cross over in route to the brain, causing the left half of each visual field to be seen by the _____ cerebral hemisphere and the right half to be seen by the _____ hemisphere.
Axons within each optic tract cross over in route to the brain, causing the left half of each visual field to be seen by the right cerebral hemisphere and the right half to be seen by the left hemisphere.
_______ occurs in two phases:
_______ _______: short term memory caused by electrical or chemical changes in neural circuits
_______ _______: involves structural changes that increase the number or effectiveness of synapses
Learning occurs in two phases:
working memory: short term memory caused by electrical or chemical changes in neural circuits
long-term memory: involves structural changes that increase the number or effectiveness of synapses
The _________ is important for the transfer of working into long-term memory.
The hippocampus is important for the transfer of working into long-term memory.
The ______ ______ are important in the retrieval of long-term memories, and are also involved with ______ _________ of faces and objects, as well as understanding ______.
The temporal lobes are important in the retrieval of long-term memories, and are also involved with memory recognition of faces and objects, as well as understanding language.
______ ______ are cells that transduce the energy of a specific signal into an electrical signal called a ______ ______.
Sensory receptors are cells that transduce the energy of a specific signal into an electrical signal called a receptor potential.
In sensory receptors, if the receptor potential is ______ enough, an ______ ______ forms.
The ____ ______ the receptor potential, the ______ the possibility of action potential formation.
In sensory receptors, if the receptor potential is positive enough, an action potential forms.
The more positive the receptor potential, the higher the possibility of action potential formation.
Temperature is sensed when ______________ respond to heat or cold.
Generally, both heat and cold receptors fire action potentials ___________ at usual skin temperatures of about 77–91*F.
Cold receptors fire ____ _____ at temperatures below 77*F, whereas warm receptors fire ____ _____ at temperatures above 91*F.
Thermoreceptors in the _____ detect _____ body temperature and activate __________ _________ to maintain appropriate body temperature.
Temperature is sensed when thermoreceptors respond to heat or cold.
Generally, both heat and cold receptors fire action potentials spontaneously at usual skin temperatures of about 77–91*F.
Cold receptors fire more rapidly at temperatures below 77*F, whereas warm receptors fire more rapidly at temperatures above 91*F.
Thermoreceptors in the brain detect core body temperature and activate homeostatic responses to maintain appropriate body temperature.
The body contains many types of _____receptors:
receptors in the skin that respond to _____, _____, or _____;
_____ receptors in many internal organs, including the intestines, stomach, urinary bladder, and muscles;
and receptors in the inner ear that respond to _____, _____, or _____.
The body contains many types of mechanoreceptors:
receptors in the skin that respond to touch, vibration, or pressure;
stretch receptors in many internal organs, including the intestines, stomach, urinary bladder, and muscles;
and receptors in the inner ear that respond to sound, gravity, or movement.
Enclosed mechanoreceptors in skin:
P______ corpuscles - ______ vibration, ______ pressure changes;
M______ corpuscles - ______ touch, ______ vibrations;
R______ corpuscles - steady ______;
M_____ disc - steady ______.
Enclosed mechanoreceptors in skin:
Pacinian corpuscles - rapid vibration, rapid pressure changes;
Meissner’s corpuscles - light touch, slow vibrations;
Ruffini corpuscles - steady pressure;
Merkel’s disc - steady touch.
Mechanoreceptors located in _____ organs, such as the stomach, intestine, rectum and urinary bladder, ______ ______ by responding to stretch.
Mechanoreceptors located in ______ sense position of ______.
Mechanoreceptors located in _____ ear detect _____.
Mechanoreceptors located in hollow organs, such as the stomach, intestine, rectum and urinary bladder, signal fullness by responding to stretch.
Mechanoreceptors located in joints sense position of limbs.
Mechanoreceptors located in inner ear detect sound.
The mammalian ear performs several different functions:
– Perceives _______
– Determines direction of _______
– Detects the _______ and _______ of the head
The mammalian ear performs several different functions:
– Perceives sounds
– Determines direction of gravity
– Detects the orientation and movement of the head
How is sound detected?
The ear converts sound waves into electrical signals
The _____ ___ captures sound waves and aids in sound source localization, and consists of 2 parts:
_____ ___: collects sound waves and directs them into the skull
_____ _____: carries sound waves to the middle ear
The outer ear captures sound waves and aids in sound source localization, and consists of 2 parts:
external ear: collects sound waves and directs them into the skull
auditory canal: carries sound waves to the middle ear
The middle ear transmits sound waves to the inner ear and consists of:
_____ _____: the eardrum
middle ear bones (_____, _____, and _____): transmit sound vibrations to inner ear
_____ _____: equalizes air pressure between the middle ear and atmosphere
The middle ear transmits sound waves to the inner ear and consists of:
tympanic membrane: the eardrum
middle ear bones (hammer, anvil, and stirrup): transmit sound vibrations to inner ear
auditory tube: equalizes air pressure between the middle ear and atmosphere
The inner ear converts _____ from sound waves into _____ _____ and consists of:
►_____ - spiral, fluid-filled tubes: the middle ear bones transfer sound energy into it by vibrating the _____ _____ _____
►_____ _____: involved in balance.
The inner ear converts vibrations from sound waves into electrical signals and consists of:
►cochlea - spiral, fluid-filled tubes: the middle ear bones transfer sound energy into it by vibrating the oval window membrane
►vestibular system: involved in balance.
Sound is converted into electrical signals in the cochlea, which has three fluid-filled compartments containing:
the ______ membrane,
the ______ membrane, and
____ ____ ____________.
Sound is converted into electrical signals in the cochlea, which has three fluid-filled compartments containing:
the basilar membrane,
the tectorial membrane, and
hair cell mechanoreceptors.
Mechanism of cochlear function:
sound waves are transmitted into the cochlea by ______ ______ ______ vibrations;
vibrations produce ______ ______ that cause the ______ ______ to vibrate;
basilar membrane vibrations cause ____ ____ to bend against the ______ ______;
______ potentials are formed, and ______ potentials are sent to the brain.
Mechanism of cochlear function:
sound waves are transmitted into the cochlea by middle ear bone vibrations;
vibrations produce fluid movement that cause the basilar membrane to vibrate;
basilar membrane vibrations cause hair cells to bend against the tectorial membrane;
receptor potentials are formed, and action potentials are sent to the brain.
Perception of Sound
______ sound vibrations bend hair cells more, which is perceived as ______ sounds (very ___ or ______ sounds can damage hair cells).
Different parts of the _______ _______ vibrate at different __________ based on sound wave characteristics, allowing for perception of different ______.
Perception of Sound
Larger sound vibrations bend hair cells more, which is perceived as louder sounds (very loud or prolonged sounds can damage hair cells).
Different parts of the basilar membrane vibrate at different frequencies based on sound wave characteristics, allowing for perception of different pitches.
The _______ _______, in the inner ear, detects gravity and the orientation and movement of the head.
The vestibular apparatus, in the inner ear, detects gravity and the orientation and movement of the head.
The vestibular apparatus is a fluid-filled tube embedded in the bones of the skull, consisting of the _______ and the _______ _______.
The vestibule contains the _______ and _______, which contain a cluster of ____ ____ and detect the direction of gravity and the orientation of the head.
The vestibular apparatus is a fluid-filled tube embedded in the bones of the skull, consisting of the vestibule and the semicircular canals.
The vestibule contains the utricle and saccule, which contain a cluster of hair cells and detect the direction of gravity and the orientation of the head.
All forms of vision use _______ - cells that contain _____________ that absorb light, which produces chemical changes. When ___________ change, _______ _______ form.
All forms of vision use photoreceptors - cells that contain photopigments that absorb light, which produces chemical changes. When photopigments change, receptor potentials form.
Arthropods utilize compound eyes made of many individual light-sensitive subunits called ________.
Each ________ forms a small part of a larger image, and each image part is pieced together to form a grainy ______ ______.
Arthropods utilize compound eyes made of many individual light-sensitive subunits called ommatidia.
Each ommatidium forms a small part of a larger image, and each image part is pieced together to form a grainy visual mosaic.
Mammal eyes have three major tissue layers:
______: white outer layer; tough ______ tissue
______: dark middle layer that ______ stray light; has rich blood supply
______: delicate inner layer; multilayered sheet of __________ and ______
Mammal eyes have three major tissue layers:
Sclera: white outer layer; tough connective tissue
Choroid: dark middle layer that absorbs stray light; has rich blood supply
Retina: delicate inner layer; multilayered sheet of photoreceptors and neurons
In the mammalian eye, light encounters the following structures before it is transduced:
►______: _________ covering over front of eyeball
►_______ ______: watery fluid that ________ lens and cornea
►____: pigmented ring of ______ that controls amount of light entering eye
In the mammalian eye, light encounters the following structures before it is transduced:
►Cornea: transparent covering over front of eyeball
►Aqueous humor: watery fluid that nourishes lens and cornea
►Iris: pigmented ring of muscle that controls amount of light entering eye
Mammalian eye structures:
_____: opening in the center of the _____
_____: transparent _____ structure that bends light
_____ _____: jelly-like fluid that _____ eye shape
_____: multilayered sheet of __________
Mammalian eye structures:
Pupil: opening in the center of the iris
Lens: transparent protein structure that bends light
Vitreous humor: jelly-like fluid; that maintains eye shape
Retina: multilayered sheet of photoreceptors
Muscles attached to the _______ ____ of the mammalian eye can contract and change the shape of the lens which allows images to be focused on the ____ of the ____ when looking at objects at different distances.
If the eyeball is too ____, the image is focused in front of the retina, which results in ________.
If the eyeball is too ____, the image is focused behind the retina which results in ________.
Muscles attached to the adjustable lens of the mammalian eye can contract and change the shape of the lens which allows images to be focused on the fovea of the retina when looking at objects at different distances.
If the eyeball is too long, the image is focused in front of the retina, which results in nearsightedness.
If the eyeball is too short, the image is focused behind the retina which results in farsightedness.
Light striking the retina is captured by _____ & _____ – photoreceptors at the rear of the retina – that transduce light stimuli, forming ______ potentials.
______-______ neurons process receptor potentials and pass forward impulses.
______ ___ at the front of the retina carry ______ ______ to brain along optic nerve.
Light striking the retina is captured by rods and cones – photoreceptors at the rear of the retina – that transduce light stimuli, forming receptor potentials.
Signal-processing neurons process receptor potentials and pass forward impulses.
Ganglion cells at the front of the retina carry action potentials to brain along optic nerve.
Each mammal eye has a ______ ______ where the ______ ______ connects to the eyeball which lacks _________, so images disappear when light passes over this spot.
Each mammal eye has a blind spot where the optic nerve connects to the eyeball which lacks photoreceptors, so images disappear when light passes over this spot.
_____ are concentrated in the _____, require relatively bright light to function, and allow for _____ _____ by detecting red, green, and blue light wavelengths.
_____ are concentrated in the _____ of the eyeball, perceive light _______ (shades of grey) and are responsible for vision in _____ _____.
Cones are concentrated in the fovea, require relatively bright light to function, and allow for color vision by detecting red, green, and blue light wavelengths.
Rods are concentrated in the periphery of the eyeball, perceive light intensities (shades of grey) and are responsible for vision in dim light.
________________ detect the presence of ____ in fluids:
- *____**: detects airborne molecules,
- *____**: detects molecules dissolved in water or saliva.
Chemoreceptors detect the presence of chemicals in fluids:
- *smell**: detects airborne molecules,
- *taste**: detects molecules dissolved in water or saliva.
_______ receptors, located in the upper nasal cavity, have hair-like ______ that protrude into a _____ layer.
Odorous molecules in air dissolve in nasal cavity _____ and bind to _______ on olfactory _______; _______ ______ are formed and sent to brain.
Olfactory receptors, located in the upper nasal cavity, have hair-like dendrites that protrude into a mucus layer.
Odorous molecules in air dissolve in nasal cavity mucus and bind to receptors on olfactory dendrites; receptor potentials are formed and sent to brain.
The tongue bears about _____ taste buds in bumpy _____.
Each taste bud contains 60-80 taste _____ _____.
Taste receptor ________ project out a taste _____.
Dissolved chemicals enter the _____ and bind to ________ on ________.
________ ________ form and are sent to brain.
The tongue bears about 10,000 taste buds in bumpy papillae.
Each taste bud contains 60-80 taste receptor cells.
Taste receptor microvilli project out a taste pore.
Dissolved chemicals enter the pore and bind to receptors on microvilli.
Receptor potentials form and are sent to brain.
Taste receptors allow the perception of ____, ____, ____, ____, and ____ flavors.
Taste receptors allow the perception of sweet, sour, salty, bitter, and umami flavors.
Pain is the perception of ______ ______.
Pain receptors (______) respond to two chemical stimuli: ______ ______, and ______, which is formed from enzymes released from damaged tissue.
Pain is the perception of tissue damage.
Pain receptors (nociceptors) respond to two chemical stimuli: potassium ions, and bradykinin, which is formed from enzymes released from damaged tissue.
What is the fundamental unit of the nervous system?
What are its functions?
neurons
Receive information
Integrate information
Conduct signals over distances
Transmit signals to other neurons, tissues, or organs
What are the steps of the axon potential, as recorded in an oscilloscope?
What causes each?
resting
rising - stimulation
peak - sodium ions entered and brought potential to around +30mV
falling - potassium ions diffuse out
undershoot - potassium continues to flow out of the cell even after the membrane has fully repolarized
What is a neurotransmitter?
Give some examples.
dopamine
norepinephrine
serotonin
glutamate
endorphins
What neurotransmitter uptake is blocked
by the use of most antidepressants?
serotonin
What ion channel is
closed during resting membrane potential
and suddenly open during the action potential?
sodium
Why does repeated use of drugs results
in a decrease in the response to the drug?
dopamine receptors decrease
What is a synapse?
site at which a neuron communicates with
other cells, tissues, or organs
What is the function of myelin in an axon?
increase speed of electric transmission
How is the intensity of a stimulus
encoded by the nervous system?
by the frequency of action potentials
and the number of neurons that are involved
What are the parts of the Central Nervous System?
brain
spinal cord
What is the function of the cerebellum?
helps coordinate movements of the body
What brain system is responsible for
primitive emotions?
limbic system
What area of the brain is involved in
higher functions?
frontal lobe
What are the functions of the spinal cord?
What are the two regions of the spinal cord called and why?
transmits signals between the brain & body
grey matter - cell bodies of motor and association neurons
white matter - surrounds grey, consists mostly of myelinated axons
What kind of neurons activate muscles?
Where are their cell bodies located?
motor neurons
ventral horn gray matter of the spinal cord
What is the function of the reticular formation?
relay and sensory filtering
How many types of memories are known?
working memory
long-term memory
What is the corpus callosum and its function?
large band of axons that divides the two hemispheres of the cerebral cortex
What colors in a PET scan indicate more activity?
warmer - yellow/red
What types of receptors are used for touch, vision, hearing, and taste, respectively?
touch - mechanoreceptors
vision - photoreceptors
hearing - mechanoreceptors
taste - chemoreceptors
What are the photoreceptors responsible for color vision?
What are the photoreceptors responsible for black & white vision?
cones
rods
What is the fovea?
area of concentration of cones
Which one has depth perception: prey or predator?
predator
What causes perception of pain?
nociceptors respond to potassium ions or bradykinin
What is biotic potential?
maximum rate at which population can increase in optimal conditions.
What is environmental resistance?
limits set by the living and non-living environments (availability of food, space, competition, interactions, natural events)
What is the equation for calculating population growth?
growth rate = birth rate - death rate
What happens in exponential growth and what type of curve describes it?
a population continuously grows at a fixed percentage of its size at the beginning of each time period
J-curve
What is carrying capacity and how does it modify the exponential growth curve?
the maximum number sustainable by their environment
turns to S-curve
What factors determine the carrying capacity of a population?
relationship between biotic potential and environmental resistance
What are examples of populations with boom and bust cycles?
cyanobacteria, lemming
What are the important density-independent factors limiting population size?
– Climate and weather,
– Hurricanes, droughts, floods, fire
– Pesticide use, pollutant release,
– Overhunting
– Specially short-lived species are affected – Boom-and bust population
What are the important density-dependent factors limiting population size?
– Predation
– Parasitism
– Competition
What advantages can a non-native species have when introduced in a new, appropriate ecosystem?
promote diversity
What is the difference between intraspecific and interspecific competition?
– Interspecific competition is between individuals of different species
– Intraspecific competition is between individuals of the same species
What are the 3 main types of survivorship curves and what are some organisms representative of each?
late loss - humans, large mammals
constant loss - birds
early loss - most invertebrates, fish
Why are population growth rates higher in developing countries than in developed countries?
limited access to contraceptives
birth rates vastly exceed death rates
children aid in family income
What can you infer from population’s age structure diagram if it looks like a pyramid?
population is expanding and above RLF
How much energy does an American use compared to the world average?
3 to 4 times as much
Why is the U.S. population still growing, compared to other developed countries?
rapid immigration
and
high survivorship
