Life Functions 2
Movement
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Movement of a cell or an entire
organism allows the organism to
find food in its environment and to
move away from predators or
other threats.
Cilia: hair like structures on the
edge of cell membranes that work
like millipede legs moving in
unison to create a wave like
motion that move the individual
cell. Some bacteria and protists
have these structures.
Movement
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Flagella: long tail like
projections from the cell
membrane that move like a
fish tail in order to allow the
cell to swim.
Pseudopods: the cell forces
the contents of the cell into
one part of the cell
membrane causing it to
extend. Protists such as
amoebas use this method
of movement.
Movement
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Hydrostatic skeleton: the muscles
are arranged in circles that contract
and push against a liquid interior in
order to change the shape of the
organism to cause movement.
Exoskeleton: a liquid is secreted
from the skin and hardens into a
shell that the muscles are attached
to. The muscles contract and relax
to pull the skeleton in different
directions. In order to grow the shell
is molted and a new one is secreted
and hardens in its place.
Movement
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Endoskeleton: an
interior solid structure
that grows with the
body. This can be
calcified bone or
cartilage. The muscles
contract to pull the
bones which bend at
joints.
Reproduction
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The process used to create
offspring and pass genetic
material from one generation
to the next.
Viral life cycles: viruses do not
possess the proper cellular
structure to reproduce. They
will inject the instructions on
how to make a virus (either
DNA or RNA) into a living cell.
From this point there are two
different cycles the virus could
fallow.
Reproduction
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Lytic Cycle: the genetic
material injected into
the living cell will be
expressed by the cell
using the instructions
to make viruses. Then
the viruses will burst
out of the host cell
killing it and go infect
other cells.
Reproduction
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Lysogenic Cycle: The genetic material becomes integrated
into the cell’s DNA. Every time the cell divides each new cell
receives a copy of the viral instructions. Eventually something
triggers the viral instructions to become active and the virus
enters the lytic cycle.
Reproduction
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Asexual: this type of
reproduction has an
evolutionary advantage in
that it can occur very
quickly allowing an
organism to increase the
size of the population and
it does not require an
organism to find a mate.
Reproduction
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Budding: type of
asexual reproduction
performed by
multicellular organisms
such as sponges and
some plants. The
organism grows a new
organism out of the
parent that is eventually
separated and
continues to grow into
an adult.
Reproduction
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Binary fission: type of asexual
reproduction performed by
prokaryotic cells in which the cell
copies the DNA and simply splits in
half.
Regeneration: some animals and
protists are capable of cutting the
organism in half and then allowing
the two halves to regenerate or
recreate the missing structures.
Mitosis: single celled protists and
green algea will perform cell
division in order to create a
genetically identical offspring.
Reproduction
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Conjugation: the major problem
with asexual reproduction is that
the offspring are all genetically
identical to the parent. This would
prevent evolution in response to a
changing environment. To solve
this problem some organisms that
reproduce only by asexual
reproduction can form tunnels
between each other and exchange
pieces of genetic material in a
process called conjugation. These
organisms include both types of
bacteria and protists.
Reproduction
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Sexual: the advantage of
sexual reproduction is the
creation of genetically
different individuals which
provides multiple options for
every trait. The
disadvantage is this
process takes longer and
requires the presence of a
partner.
Reproduction
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External fertilization: in this
type of reproduction both the
egg and sperm are released
into the environment.
Fertilization (the fusion of egg
and sperm) and development
occur outside the body.
Normally the parents do not
care for their offspring. For this
reason thousands of eggs and
even more sperm are released
to ensure the survival of at
least some offspring.
Reproduction
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Internal fertilization: requires the sperm
to enter the body of the female and
fertilize the egg. Being that it is more
likely that the sperm and egg will meet,
not as many gametes are produced.
• Bryophytes: the sperm must swim
through a layer of water to the egg.
• Spore production: once the sperm
and egg fuse the plant creates a
spore which will grow into the next
generation. This is different from a
seed because it does not contain a
food source for the embryo.
Movement Review Questions
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What does moving allow organisms to do?
What are cilia and what type of organisms have these structures?
What is a flagella and how does it function?
What are pseudopods, how do they function, and what types of
organisms use these structures?
How do protists that do not have cilia, flagella, or pseudopods move
around their environment?
What is a hydrostatic skeleton and what types of organisms have
them?
What is the difference between an endoskeleton and exoskeleton?
What types of animals have an endoskeleton? Exoskeleton?
What is molting and what does it allow an animal to do?
What is the advantage of having joints in the skeleton?
Reproduction
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Pollination creating seeds: pollen
carries the sperm from the male part
of a plant to the female part of the
plant where the egg is located. In
gymnosperms the plant makes male
and female cones. These plants
depend on the wind to carry pollen to
the female cones so they must make
much more pollen than the flowering
plants that attract animals to carry the
pollen directly to the next flower.
Angiosperms create flowers where
the anther produces the pollen and
the pistil contains the eggs.
Reproduction
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Oviparous: after fertilization
occurs the fertilized egg is
wrapped in several layers of
membrane and laid outside the
body to develop. Examples
include birds, most reptiles,
most amphibians and
monotreme mammals (echidna
and platypus).
Reproduction
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Ovoviviparous: after fertilization occurs
the fertilized is wrapped in several
layers of membrane and the egg is
held inside the body for protection.
Examples include sea horses, some
snakes, and some frogs.
Reproduction
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Viviparous: after fertilization the embryo implants and develops
inside the mother. In marsupial mammals the baby is born
premature and moves to a pouch where the nipple is located. The
rest of development occurs in the pouch with milk providing the
nutrition. In placental mammals a specialized organ is created
that allows the offspring to fully develop inside of the mother.
Reproduction Review Questions
• What are the two ways a virus can reproduce? Explain each cycle.
• What are the benefits and disadvantages of asexual reproduction?
Sexual reproduction?
• What is budding? Is this asexual or sexual reproduction?
• What is binary fission? Is this asexual or sexual reproduction?
• What is conjugation? What is the purpose of conjugation and what
types of organisms use this process?
• Explain why animals that use external fertilization tend to make
more gamete cells and offspring.
• What are oviparous animals? Ovoviviparous animals? Viviparous
animals? Include examples of each.
• (Review) What are monotreme mammals? Marsupial mammals?
Placental mammals? Include examples of each.
Response
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Organisms have developed specialized
structure in order to gather information from
the environment and respond to these
stimuli. The structures can be divided into
two groups: the structure used to process
information and structures used to gather
information
Response
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Process information
 In single celled organisms the
nucleus will process the
information received from the
environment and formulate a
response.
 Nerve net: nerve cells are used
to transport information
throughout the body. The cells
are evenly distributed the
information is passed from one
cell to the next until all of the
cells know what is occurring.
Response
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Ganglia: a group of nerve cells
that collects and process
incoming information. This is
different from a brain because
there are not specialized regions
to perform different tasks.
Brain: a group of nerve cells that
process incoming information.
The brain has specialized
structures that divide up tasks
such as processing sight and
controlling involuntary functions.
Response
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Specialized structures will collect
information from the environment in
order to help the organism understand
what is occurring around it.
 Eye spots: are used by some
protists and simple animals such as
flatworms to detect the presence of
light.
 Eyes: used by many animals. There
are different types. Complex eyes of
insects have many lenses allowing
them to see movement better than
eyes with a single lens while other
eyes can see color very well.
Response
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Ears: Used by animals to hear their
surroundings. Some animals have just
a tympanic membrane and are unable
to hear distinct sounds while others
have external ear structures allowing
them to collect sound more efficiently
Taste: can be used to distinguish
between organisms.
Smell: can be used to locate predators
or prey.
Lateral line: found in fish and
amphibians, used to detect
disturbances in the water.
Response Review Questions
• How do single celled organisms process
information from the environemnt?
• Explain how a nerve net works. Provide
examples of animals that use this system.
• Explain the difference between ganglia and
brain.
• What is a lateral line, what does it do, and
what types of organisms have this structure?
Behaviors
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Behaviors can be divided into two groups.
 Learned behaviors which are the result of an animal’s
experiences. Allows for adaptation of behaviors increase the
chances of survival. It is generally believed that only animals
with complex nervous systems can learn. The amount of
learning an animal is capable of is determined by life span and
amount of parental care. Animals with shorter life spans and
little to no parental care have fewer learned behaviors.
 Innate behaviors are encoded in the DNA of the organism and
inherited like physical traits. This means all organisms will
perform these types of behaviors the same from birth no
matter the conditions they are raised in.
Examples of Innate Behaviors
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Suckling: a reflex that exists in
mammals that allows them to feed
from their mothers instinctively
Taxes: some organisms such as
insects exhibit this type of behavior
which results in movement either
toward or away from the stimulus.
Migration: the movement of
organisms to a new location in
response to the time of year
(mating time or to find food in the
different seasons)
Examples of Innate Behaviors
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Circadian rhythm: the 24
hour living pattern of an
animal
Estivation: lowering of body
temperature to go into a
state of dormancy to
escape extremely hot
conditions.
Hibernation: lowering of
body temperature to go into
a state of dormancy to
escape extremely cold
conditions.
Examples of Learned Behaviors
*****ADD TO YOUR NOTES*****
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Imprinting: Rapid form
of learning that occurs
at a young age and is
essential for survival.
Examples include prey
animals such as zebras
learning to walk in
hours and ducks
fallowing their mom.
Examples of Learned Behaviors
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Habituation: Animals learn
not to respond to a
repeated action.
Reasoning: the ability to
solve unfamiliar problems
in new situations.
Trial and error learning:
process of elimination
where an animal tries all
solutions to a problem in
order to discover the
correct one.
Examples of Learned Behaviors
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Classical conditioning: An animal learns to associate a stimulus
with a response that would not normally occur. Ex. Pavlov did an
experiment using a dog and a bell. He would ring the bell and
give the dog a treat. Eventually the dog would salivate at the
sound of the bell even if he was not given a treat.
Social Behaviors
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Social behaviors can be learned, innate
or a combination of the two. These
behaviors are used to communicate
between organisms.
 Territoriality: the physical space an
animal defends against others of the
same species and gender. The animal
may be defending breeding area,
feeding are, or mates. This reduces
conflicts, controls growth, and ensures
efficient use of the environment.
Pheromones which are chemicals
secreted and recognized by the same
species are used to mark territory.
Social Behaviors
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Aggression: used to
intimidate another animal so
that fighting is not required.
Fighting carries the risk of
injury even to the winner
which decreases the chances
of surviving. Animals fight or
threaten one another to
defend young, territory, or
resources like food.
Aggressive behavior includes
postures, bird calling, teeth
bearing, or growling.
Social Behaviors
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Courting: Behavior that males
and females carry out to
attract mates. Animals use
elaborate color patterns,
songs, dances, and decorated
homes to attract mates.
Dominance hierarchy: A form
of social ranking among family
groups. The term “pecking
order” comes from the
behavior of chickens. The top
ranking chicken pecks all
others and the lowest gets
pecked by all other chickens.
Behavior Review Questions
• What is the difference between innate and
learned behaviors?
• What types of behaviors can evolve and why?
• How can you tell if a behavior is innate?
• List and explain six innate behaviors.
• List and explain four learned behaviors.
• Are social behaviors learned or innate?
• List and explain four social behaviors.