Chapter 1 Flashcards
What are the 7 characteristics in defining life?
1) Order
2) Ability to process energy /metabolize
3) Growth / development
4) Reproduction
5) Responsive to stimuli
6) Maintain homeostasis
7) Adaptation
Homeostasis
The ability to maintain a constant internal environment.
Homeothermic
Capable of regulating body temperature within a small safe temperature range.
(Seen in all mammals)
Adaptation
A long term, inter-generational change due to natural selection. (Meaning there was actual alteration in genes overtime)
Ex. A species grows more fur overtime to combat the cold
Acclimation
A short term response to the environment. (No changes made to the genes)
Ex. Putting on a jacket to combat the cold
Hierarchical organization of life
Chemical:
Molecule-> organelle -> cell-> tissue-> organ-> organ system->
Ecological:
organism-> population-> community-> ecosystem-> biosphere
Molecules
Made by atoms that combine chemically.
Four most important molecules:
1) carbohydrates
2) lipids
3) proteins
4) nucleic acids
Organelles
Highly specialized structures within a cell, each containing its own specific function.
Ex. Mitochondria, lysosomes
Cell
The simplest part of living matter that can carry on all the activities necessary for life.
Made up of 2 subdivisions:
1) cytoplasm
3) organelles
Tissues
A group of cells that have a similar function that bond together to carry out that purpose.
Ex. Muscle tissue
Organs
Many tissues that are arranged into functional structures.
Ex. Heart, stomach
Organ systems
A group of organs working together to perform complex functions.
Ex. The digestive system
Organism
All the organ systems functioning together to sustain life.
Populations
Members of one species that live in the same area.
Community
The population of organisms that inhabit a particular area and interact with one another.
(Could be compromised of hundreds of different types of lifeforms)
Ecosystem
A community along with its nonliving environment.
(Could be as small as a pond, or as fast as the Great Plains)
Biosphere
The planet earth which contains all of the ecosystems and their inhabitants.
Ecology
The study of how organisms of a community relate to one another, and with their nonliving environment.
Describe the flow of energy and nutrients within an ecosystem
Energy enters through sunlight, which then gets converted into chemical energy by plants. The chemical energy resides in producers, and can be eaten by consumers in order to carry out their functions. The energy is then converted into heat through metabolic processes, and everything decomposes and the cycle continues
DNA
Stores genetic information and controls the structure and function of all cells. It also provides instructions or how to make proteins.
(Differences in DNA sequences creates diversity of life)
Evolution
The gradual change in living things from one generation to the next.
(Changes in genes with the changing environment)
Natural selection
1) population with varied inherited traits.
2) elimination of individuals with undesirable traits, and reproduction of individuals with traits suited for survival.
3) increase of frequency in traits that enhance survival and reproductive success
Hypothesis
A testable explanation for a set of observations based on available data.
The key steps in the process of science
1) Observations
2) Questions
3) Hypothesis
4) Predictions
5) Testing
The scientific method
Wondering why something is the way that it is, and coming up with a hypothesis that attempts to answer the question by using tests to come to a conclusion either in support of the hypothesis or not.
Deductive reasoning
The process of making predictions based on the hypothesis and then testing them.
Ex. Flashlight won’t turn on:
Hyp 1 - batteries are dead
Prediction - replacing batteries will fix it.
Hyp 2 - bulb is burnt out
Prediction - replacing bulb will fix it.
Theory
A widely excepted explanation that is broader than a hypothesis. It will also generate new hypotheses, and is supported by large amount of evidence.
Scientific principle / law
A theory that over a long period of time has yielded true predictions, and is universally accepted.
The first law of thermodynamics
The law of energy conservation:
Energy and mass can be transformed, but there’s always the same total amount available.
i.e. Energy/matter cannot be created or destroyed.
The second law of thermodynamics
The entropy law:
In all natural processes, the entropy of the world always increases.
i.e. all things tend towards maximum entropy (meaning maximum randomness.)
What are the 2 key evolutionary observations made by Darwin?
1) Individuals vary and traits and traits are passed from parents to offspring.
2) A population can produce more offspring than the environment can support.
(This calls for natural selection: only those traits best suited for survival remain)
Additive effect
Taking one thing that worked + another different successful result, and adding them together expecting double the success.
Antagonistic effect
Taking two different successful results, but when added together, they cancel each other out .
Synergistic effect
Taking two successful results, adding them together, and rather than the success doubling, it times by 10 or 20…etc. This could create something deadly since they amplified each other.
