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55 Cards in this Set
- Front
- Back
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DNA
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the signature molecule of cells that encodes protein-building instructions. everything is guided by this. it determines your looks, personality, etc. we have 9 feet of this in each cell.
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How many can proteins can the four bases of DNA make up?
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50,000
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Energy
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the capacity to do work. a constant stream of this is required in all living things.
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Metabolism
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The capacity to obtain and convert energy from surroundings and use it to maintain, grow, and produce more cells.
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Life is organized
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OCTOOMPCE
1. organelle- inside all cells except bacteria, preforms a special task 2. cell- smallest unit to live or reproduce. 3. tissue- cells and surrounded substances working together 4. organ- multiple tissues working together 5. organ system- such as circulatory; heart lung and vessels 6. multi-celled organism- humans 7. population- all living things of the same species in a place 8. community- all living things in an area 9. ecosystem- living and nonliving things in an area |
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Life requires energy
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Energy from the environment used to build new structures repair old ones and reproduce
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Producers
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make their own food (plants//photosynthesis)
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Consumers
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eat other organisms
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Decomposers
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break down dead things
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Interdependence of producers//consumers//decomposers
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consumers depend on other consumers and producers for their food//producers need the consumers bc when they die and decompose, plants take in the nutrients through the soil//decomposers need living things to die to obtain energy from them
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Passenger Pigeons
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Once most numerous bird on the planet, est 1-4 billion. If a flock went over your town, they would block out the sun. stupid. Used for meat. Nested in really large numbers and easy to kill. Poor people/slaves mostly ate these as 2 pigeons for a penny. Could kill 50000 a day for five months. Last one died in captivity in 1906. we wiped them out
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Life maintains internal constancy
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need homeostasis, or the state of internal equilibrium. body temp, pH, water balance(most important one).
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Life reproduces, grows, and develops
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asexual (one parent, no sex, no variation)
versus sexual (two parents, sex which takes more energy, variation) |
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Life evolves
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living things adapt to changing conditions
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Adaptation
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any trait that helps an organism survive and reproduce.
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Evolution
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a change in a population over time
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Natural Selection
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Organisms with the best combination of genes survive and reproduce
As individuals that have inherited particularly adaptive traits contribute more offspring, these traits become more common in population |
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Pepper Moths
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Either white or black. Better to be white for camouflage- birch trees. Black is a rare mutation. Industrial revolution soot covered trees black. Now it was better to be black. Genes for black color become more common.
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Antibiotic Resistance
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When bacteria are exposed to antibiotics, they are killed but some survive. Bacteria will eventually become resistant.
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Marine Iguanas
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only aquatic lizards. live on galapagos islands. have claws that help them hang on to rocks. hold breath to dive ~30 feet.
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Classification of Living Organism (dear king phillip came over for good soup)
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begin broad, get narrow
1. Domain 2. Kingdom 3. Phylum 4. Class 5. Order 6. Family 7. Genus 8. Species |
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6 Kingdoms (aepfpa)
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Archaebacteria
Eubacteria Protista Fungi Plantae Animalia |
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Hypothesis
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a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
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Theory
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A testable hypothesis about the cause or causes of a broad range of related phenomena.
Remains open to tests, revision, and tentative acceptance or rejection. trying to move towards what is true. |
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Experiment
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a test of hypothesis under controlled conditions
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Control Group
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a group separated from the rest of the experiment where the independent variable being tested cannot influence the results. provides basis for comparison.
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Scientific Method Steps
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Observations
Hypothesis Experiment and data collection Analysis and peer review |
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Why is larger sample size better?
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the more credible results bc they happened to a larger number
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Variables
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a changeable element of an experiment. have to be consistent. ex: water, sunlight, ph of the water/soil, pests
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Element
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Fundamental form of matter – cannot be broken down into something else
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What elements are living things mostly made of?
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nitrogen, hydrogen, oxygen, carbon
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Atom
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the smallest unit of an element
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Proton
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positive charge, mass 1, located in nucleus
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Electron
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negative charge, mass 0, orbits atom
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Neutron
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no charge, mass 1, located in nucleus
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Isotope
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an atom with the same number of protons, but different numbers of neutrons. rare. interact chemically with other atoms in the same way
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Radioisotope
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unstable, radioactive isotopes. dangerous sometimes.
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atomic number
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a. number of protons in the nucleus
b. identifies the element ex: all carbon atoms have 6 protons c. number of protons = # electrons d. electrons determine chemical reactivity |
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Mass number
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a. number of protons + number of neutrons
b. 12C carbon is 12 6 protons + 6 neutrons c. This number is variable since the # of neutrons may vary in an atom |
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Examples of isotopes
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carbon and plutonium
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How are isotopes useful?
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1. dating of rocks and fossils
2. markers for tracing the path of an element in a metabolic pathway. 3. diagnosing diseases (Iodine 123) 4. Nuclear power, weapons of mass destruction |
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Chemical bond
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a union between atoms caused by the sharing or exchange of electrons.
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Molecule
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two or more atoms bonded together
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ion
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an electrically charged atom.
a. caused by the loss or gain of electrons |
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ionic bond
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ions of opposite charges attract each other
example : sodium chloride - NaCl are relatively weak and dissolve in water (helps them move around in the body) |
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covalent bond
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sharing of electrons w/ strongest bond.
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Polar
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atoms share the electrons unevenly. Positive and negative poles are created .
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Non-polar
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atoms share the electrons evenly.
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Hydrogen bond
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1. weakest of the chemical bonds
2. biologically very important bonds 3. occurs between the hydrogen atoms of polar compounds. 4. important in the properties of water and the structure of DNA. |
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electronegativity
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the measure of an atom’s ability to attract electrons
bigger attracts more electrons |
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hydrophilic
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water-loving polar compounds
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hydrophobic
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water-hating polar compounds
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temperature
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a measure of molecular motion
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cohesion
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large numbers of hydrogen bonds provide cohesion
(surface tension) |
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why is water a temperature stabilizing molecule
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large amounts of energy are required to change the temp of water.
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