Themes in the Study of Life Chapter 1&2

Flashcard maker : Darryl Wooten
Darwin’s Book
Origins of Species
Themes in the study of life
1. The living world is a hierarchy
2. cells are the basic units of structure & function
3. the continuity of life is based on DNA
4. structure and function are correlated
5. organisms are \”open\” systems
Why is earth going down in species?
Human population is increasing, hurting our ecosystem, main reason= food shortages, survival of the fittest, war
How do we know what is alive and what is not?
1. Order
2. Reproduction
3. Growth
4. Energy Utilization
5. response to environment
6. homeostasis
7. evolutionary adaptation
8. the cell is the basic unit of life
Order
1. living things are highly organized in structure and function
2. analyzing biological structure gives us clues about what it does and how it works
3. structure and function are related at all levels
Reproduction
1. Organisms produce their own kind
2. Life on earth uses the nucleic acid and code for Heritable information – DNA
Growth
increase in size
Development
increase in complexity
Growth and Development
Organisms increase in size and complexity
Life grows by internal changes
Energy Utilization
1. organisms take in energy and transform it to do work.
2. organisms are \”open\” systems, they must continually take in energy
Response to the Environment
1. organism respond to changes or stimuli in their environment
2. the speed of the response may be fast or slow
Fast response to stimuli in the environment
venus fly trap
Homeostasis
organism maintain their internal environment within tolerable limits
Homeo
Same
Stasis
State
Evolutionary Adaptation
1. Species not organisms change over time as they adapt to their environment
2. organisms must adapt, move or die!
Biology can be described as the study of the science of ____________.
Life
After making careful observations, scientists construct a __________. which is a suggested explanation that accounts for those observations
hypothesis
the experimental testing of a hypothesis formulated after the systematic objective collection of data us called the __. method
scientific
From th time of the Greek Fratosthenes to the present day, scientists have been using the method of ___ reasoning in which general principles are applied to the analysis of specific cases
deductive
a hypothesis is tested by a(n) ___
experiment
a(n) ___. is a hypothesis that is supported by a great deal of evidence
theory
Experiments are carried out to test the hypothesis by changing one variable at a time and including a(n) _______ condition in which the variable is unaltered
controlled
specimens or rock strata which show progressive changes in characteristics of earlier organisms are called ____.
fossils
Darwin concluded from his voyage that the process of ___ had been responsible for the patterns of distribution and relationships of organisms
evolution
Natural ___ explains how the traits of organisms that leave more offspring become more common in succeeding generations
selection
Science is not based on
observations
in science when general principles are arrived at from the examination of specific hypothesis (cases) it is called
inductive reasoning
What is not true about a hypothesis?
it always withstands the test of experiments
hypotheses that are consistent with the results of experimental testing are
conditionally accepted
The scientific process involves
rejection of hypotheses that are inconsistent with experimental results
A valid experiment must include
a variable that is altered in specific way/a control in which the variable is left unaltered/both control and the variable, which are treated in parallel/only one variable to be tested
The theory that provides a conceptual framework that unifies biology as a science is
the theory of evolution
the naturalist on the ship HMS beagle was
Darwin
The proposal that one type of organism can change gradually into another type over a long period of time is known as
evolution
What was not one of the beliefs of Darwin’s time?
Operation of natural laws produces constant change and improvement
Darwin studied the giant tortoises
on the Galapagos Islands
Darwin’s thinking about evolution was influenced by observations made on all of the following except
leaves falling from gingko trees
Besides Darwin the theory of evolution by means of natural selection was also independently proposed by
Alfred Wallace
Darwin described which of the following as \”those individuals that possess superior physical, behavioral, or other attributes are more likely to survive than those that are not so well endowed.\” and thus are more likely to pass their traits to the next generation?
geometric progression
a key contribution to Darwin’s thinking was the concept of limits put on the geometric growth of populations by nature, originally proposed by
Thomas Malthus
Recent discoveries of microscopic fossils have extended the known history of life to about
3.5 billion years ago
modern pieces of evidence that corroborate Darwin’s theory of evolution include all of the following except
human population growth
a critical requirement of Darwin’s theory is
genetic variation is possible in nature
the same basic array of bones are modified to give rise to the wing of a bat and the fin of a porpoise. such anatomical structures are called
homologous
structures that have similar structure and function but different evolutionary origins are called
homologous
somewhat more than 100 years ago scientists discovered the fossil remains of a 150 million-year old bird known as
Archaeopteryx
Which of the following is not required for evolution to take place
artificial breeding
Gingko trees may lose their leaves in response to decreasing day length
hypothesis
Plants adapt to seasonal changes in their surroundings
theory
Plants are raised under artificial lights turned off and on by an electric clock. some are given long periods of light, other short periods.
experiment
walnut trees may respond to the advancing season in the same way that gingko trees do.
deductive reasoning
gingko trees are known to lose their leaves at a certain time each year throughout the united states. they must behave the same way in china.
inductive reasoning
the negatively charged particles with almost no mass, orbit around the nuclear core of the atom. these are named
electrons
the number of protons in a given atom is equal to its ___ number
atomic
____ of an element have atoms with the same atomic numbers but different number of neutrons
isotopes
In chemical reactions, the gain of an electron is called ___
reduction
when atoms gain or lose electrons, they become negatively or positively charged. they then are attracted to each other by ___
ionic bonds
a(n) ________ bond forms when two atoms share a pair of electrons
non-polar covalent
approximately 90% of the atoms of all organisms are oxygen and hydrogen, reflecting the predominant role of ___ in living systems
water
water molecules are polar with ends that exhibit partial positive and negative charges. such opposite charges make water molecules attract each other through weak bonds called __
hydrogen bonds
the __ of water molecules determines its chemistry and thus the chemistry of life
hydrogen
___ is defined as the negative logarithm of the hydrogen ion concentration in the solution
pH scale
a substance that acts as a reservoir for H+ ions, opposing any increase or decrease in concentration, is a(n)
buffer
a proton
has one positive charge, has one dalton of mass, and is found in the nucleus of the atom
an electron
has one negative charge, has one 1/1840 dalton of mass, is found in the nucleus called the orbital
the atomic number of an element is equal to the number of ___
protons only
ordinary oxygen has an atomic mass of 16 and an atomic number of 8, this means that the number of neutrons in this type of oxygen is
8
atoms tend to be neutral in nature. therefore in such atoms the number of protons must be equal to the number of
electrons
oxygen ordinarily has 8 protons and 8 neutrons. another rare form has two extra neutrons. these two forms are
oxygen isotopes
atoms in which the number of electrons does not equal the number of protons are known as
ions
the chemical behavior of atoms is determined by
its electrons
in the crystal matrix of ordinary salt, the sodium and chlorine are held together by
ionic bonds
four most abundant atoms found in living things
carbon, hydrogen, nitrogen, oxygen
because oxygen is more electronegative than hydrogen, the water molecule is
polar
water molecules are attracted to eachother because of the opposite charges created by partial charge separations within the molecules. these attractions are called
hydrogen bonds
nonpolar molecules tend to aggregate in water because they are forced to come into close proximity with each other due to
hydrophobic interactions
when water ionizes, it produces equal amounts of hydrogen and hydroxide ions, which can reassociate with eachother water is thus
a base and an acid
compared with a pH of 7, a solution of pH 5 has
100 times the hydrogen concentration

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