Midterm Review Flashcards
What are the levels of organization of life?
Atom, Molecules, Cell, Tissue, Organ, Organ System, Organism, Population, Community, Ecosystem, Biosphere
Which level is the most inclusive?
Biosphere
Which level is the least inclusive?
Atom
Which level includes non-living substances like soil and rivers?
Ecosystem
Which level includes only members of the same species?
Population
Which level includes members of many species?
Community
How are species named?
Homo. Sapiens
Genus. Species
What are the three domains of life?
Eukarya, Eubacteria, Archaea
Cells in which domains do not have nuclei?
Bacteria and Archaea
What is the smallest unit of life?
Cell
What are producers?
Make their own food using energy and raw materials from non biological resources (photosynthesis)
What are consumers?
Obtain energy and nutrients by feeding on other organisms (mammals)
In which domain are halophiles classified?
Eubacteria and archaea
Are halophiles prokaryotic or eukaryotic?
Prokaryotic
What are some examples of unicellular organisms?
E.coli, bacteria, protists
What are some examples of multicellular organisms?
Plants and animals
In science, what is a control group?
Group not exposed to the independent variable being tested
In science, what is an experimental group?
Group of individuals who have certain characteristics or receive a certain treatment
What is a scientific theory?
A hypothesis that has not been disproven after many years of rigorous testing
What is a hypothesis?
Testable explanation for a natural phenomenon
How do you reduce bias in a study?
Use a blind study
By designing experiments that yield quantitative results
What is a bias, and how can scientists avoid it?
Bias is a preference for or against one idea, thing, or person. Scientists can avoid bias by conducting blind studies
What is the octet rule?
The tendency of atoms to prefer to have eight electrons in their valence shells
What determines the identity of an atom?
Basically the atomic number
How do you determine the number of protons, electrons, and neutrons?
Protons are the same as the atomic number
Electrons are the same as protons and neutrons
Neutrons are the atomic mass subtracted from the atomic number
How do you determine the number of valence electrons in an element?
By what group they fall under in the periodic table
How can an atom become an ion?
When an atom loses or gains an electron
Where are protons, neutrons, and electrons located in an atom?
The nucleus
What is an isotope? How can one element have more that one isotope?
Same atom, different number of neutrons
What is an ionic bond?
Atoms with more or less electrons than protons
What is a covalent bond?
Sharing an electron pair between two atoms
What kind of bonds link amino acids?
Peptide bonds
What kind of reaction is used to break down polymers into monomers?
A hydrolysis reaction
What factors limit cell size?
What is a biofilm?
Community of different types of microorganisms living within a shared mass of slime
What kind of cells can have flagella?
Bacteria, archaea, and eukarya
What is cell theory?
One of the foundations of modern biology
What is the fluid mosaic model of cell membranes?
A cell membrane can be considered a two-dimensional fluid of mixed composition
What cells organelles are found in ALL cells?
Golgi bodies, mitochondria, and ER
What is the function of the cell membrane?
To function as a selectively permeable barrier separating an internal environment from an external one
What is the endomembrane structure?
Series of interacting organelles between the nucleus and plasma membrane
What is the endomembrane function?
Make and modify lipids, proteins, and recycles molecules and particles such as worn out cell parts, and inactivates toxins
What are the characteristics of life?
Hereditary info is passed to offspring
Adaptation to environmental change
Requirements for nutrients
How do fungi obtain nutrients?
They absorb the nutrients around them
How many electrons can the first and second valence shells hold?
The first shell can hold 2 and the second shell can hold 8
What is the difference between a solvent, solute, and solution?
Solvent- the material that usually decides the solutions physical state
Solute- the product that the solvent dissolves
Solution- the “equivalent”
What is a glycogen?
A polysaccharide used for energy storage by animals
What are the types of lipids?
Triglyceride, phospholipid, and sterols
What is a sampling error and how can you minimize it?
Sampling errors are not providing enough samples during a study. You can avoid this by ensuring you have an appropriate sample size for your study.
What are hydrophobic interactions? What role do they play in cell membranes?
The tendency of non polar molecules to aggregate in water solutions
What is the relationship between a population and community?
A population is a group of individuals that belong to a particular species, living in a particular geographical area at a particular time. On the other hand, a community is two or more populations, living in the same geographical area at a particular time.
What is homeostasis?
Process by which an organism keeps it’s internal conditions within a range that favors survival by sending and responding to change
What is hydrolysis?
The breakdown of large molecules by enzymes and the addition of water
What is a nutrient?
A nutrient is a substance necessary for survival that an organism cannot make itself
Is there a one way flow of nutrients or are they cycled?
Energy flows one way
Nutrients are cycled
How are two strands of DNA held together?
By hydrogen bonds between pairs of bases (A-T, C-G)
What is the composition of a triglyceride?
Glycerol fatty acid chains
What are saturated fats?
Fatty acid chains that have a single bond
Where are saturated fats found naturally?
Red meats or dairy products
Are saturated fats usually liquid or solid at room temperature?
Solid
What are unsaturated fats?
Contain one or more double bonds
Where are unsaturated fats found naturally?
Food from plants such as vegetable oil and seeds
Are unsaturated fats usually liquid or solid at room temperature?
Liquid
