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What is 1 + 3?
scientific study of life
List the 7 properties of life
order, regulation, growth/development, energy utilization, response to environment, reproduction, evolution
What are the two main processes that ecosystems depend on?
cycling of nutrients and flow of energy
Which of the following is not recycled but is lost from ecosystems?
Which structure can perform all the activities required for life?
Which is larger? Prokaryotic or eukaryotic cell?
Are humans composed of prokaryotic or eukaryotic cells?
What name is given to the functional compartment of a cell?
The DNA of a eukaryotic cell is found within what organelle?
What is a gene?
the unit of inheritance that transmits info from parent to offspring
Which has more experimental support, a hypothesis or a theory?
Why does antibiotic resistance evolve in bacteria?
the antibiotic kills most of the bacteria, those that are resistent survive and proliferate
What theory states that all living things are composed of cells?
What type of microscope would be best for studying the detailed structure of the surface of a plasma membrane?
scanning electron microscope
What are the two basic cell types?
eukaryotic and prokaryotic
A cell lacking a nucleus is what kind of cell?
A cell with a nucleus and cell wall is what kind of cell?
What stores information necessary to produce proteins?
The structural combination of DNA and proteins forms what?
Most human cells contain how many chromosomes?
Where does protein synthesis take place?
Information is transferred from the nucleus to ribosomes via what?
Based on its function in detoxifying drugs, you would expect to find a large amount of smooth ER in what kind of cells?
What structures move proteins from the ER to the Golgi apparatus?
What is the function of the Golgi apparatus?
receives, refines, stores, and distributes chemical products of the cell
Which part of the cell is most like the shipping center of a factory?
Lysosomes are responsible for what?
breaking down large molecules
What are vacuoles?
membrane sacs that bud from the ER, golgi and plasma membrane
A protist that contains contractile vacuoles most likely lives in what environment?
Plant cells are characterized by the presence of what two structures?
cell wall and central vacuole
Which organelle is responsible for photosynthesis?
What is the function of microtubules?
guiding movement of chromosomes when cells divide, movement of flagella and cilia, and cell shape
DNA and RNA are polymers composed of what?
If adenine makes up 20% of the bases in a DNA double helix, what percent of the bases are guanine?
In a DNA double helix, adenine and guanine pair with what?
thymine and cytosine
If one strand of DNA double helix has the sequence GTCCAT, what is the sequence of the other strand?
Who discovered the structure of DNA?
James Watson and Francis Crick
Evidence for the spiral nature of DNA came from what?
What type of chemical bond joins the bases of complementary DNA strands?
After replication, how many old and new strands of DNA exist?
2 old and 2 new
The modern phrasing of Beadle and Tatum's hypothesis about relationships between genes and their product is one gene-one what?
What name is given to the collection of traits exhibited by an organism?
How many nucleotides make up a codon?
The shared genetic code of all life on earth is evidence of what?
What is transcription?
synthesis of RNA on a DNA template
If a strand of DNA has the sequence AAGCTC, transcription will result in a single RNA strand with what sequence?
What protects mRNA from attack by cellular enzymes?
Cap and tail
Translation converts the information stored in RNA to what?
the RNA that is translated into polypeptide is what kind of RNA?
What is the smallest number of nucleotides that must be added or subtracted to change the triplet grouping of the genetic message?
What s the ultimate source of all diversity?
Viruses that infect bacteria are called what?
How can bacteriophage DNA be spread from cell to cell without causing cell death?