AP Bio unit 2 Review Exam Questions with 100% Correct Answers All cells have? Correct Answer DNA, Cell membrane, CHONPS, ribosomes, cytoplasm What are the two different types of cells? Correct Answer Prokaryotes and Eukaryotes What are the exceptions to the two cell types? Correct Answer Viruses (can not preform
life activities on their own) made of: DNA, RNA, Protein coat
Who has prokaryotic cells? Correct Answer -Eubacteria -Archaebacteria who has eukaryotic cells? Correct Answer -Animalia -Plantae -Fungi -Protista What 3 domains does the phylogenetic tree include? Correct Answer Eukarya, Archae, Bacheria What do prokaryotic cells include (other that what all cells have)? Correct Answer Cell wall, No nucleus, No membrane bound organelles, older, smaller, simpler, unicellular, circular DNA What do eukaryotic cells include (other that what all cells have)? Correct Answer some cell walls, nucleus, membrane bound organelles, younger, larger, multicellular and unicellular, linear DNA
Very first living cells: Correct Answer -Prokaryotes
-Heterotrophs (eats other things for energy) -Asexual reproduction
-Anaerobic: does not need/use oxygen (O2 gas)
-Have DNA Primordial soup Correct Answer A mixture of organic molecules in liquid water, created from an atmospheric gases on early earth RNA world hypothesis Correct Answer -Proposes that RNA was the precursor of life
-Evidence: RNA can carry genetic information and can act as an enzyme
Ribozymes Correct Answer a molecule made of RNA that can catalyze a chemical reaction 1 / 2
Protocell Correct Answer a collection of organic molecules such as RNA, surrounded by a fatty acid membrane, that may have given rise to the first cells Important factors in the origin of life: Correct Answer -Chemical evolution - protocells were able to absorb molecules from the environment for energy -could replicate themselves -pass on info to offspring
Other important steps: Correct Answer -DNA replaced RNA as main info molecule
-DNA is more stable than RNA (RNA breaks easily because it is single stranded) -RNA mutates more often than DNA Miller and Urey Experiment Correct Answer 1953, mixed H20, H2, CH4, NH3 in a glass bulb, added electrical energy (stimulating lightening), cooled gases into liquid, discovered amino acids in the mixture. Contribution: showed it was possible to create some "building blocks of life" in early earth condition Cyanobacteria Correct Answer -aquatic and photosynthetic -quite small and usually unicellular, though they are often growing in colonies large enough to see -the oldest known fossils -still around, they are one of the largest and most important groups of bacteria on earth What does cell volume determine? Correct Answer How much nutrients a cell needs to live and how much waste it produces.-more volume=more needed, more waste produced What does cell surface area determine? Correct Answer How much space the cell has to transport molecules in and out -more surface area=more space for bringing in nutrients and removing waste Does a cell want a large surface area to volume ratio or small? Correct Answer Large because it gives more space to transport nutrients, and less volume to need stuff to create waste
What happens as a cell grows? Correct Answer Its SA:V ratio decreases
Volume increases at a faster rate than surface area why? Correct Answer volume is a cubic measurement while surface area is only a squared measurement.Cell limitations Correct Answer -Diffusion limits size -DNA content limits size -Surface area to volume ratio limits size Supplying the cells needs Correct Answer -Everything that enters and leaves a cell must come through its cell membrane. This would include nutrients, gases and waste
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