AP BiologyExam Review
60% multiple choice
40% free response
Atoms Molecules Organelles Cells Tissues Organs Systems Organism species Population Community Ecosystem
Organizing life
Experimental design free response Problem Hypothesis Materials/procedure Control setup/baseline Independent and
dependent variables Constants & variables Qualitative &
quantitative data Data interpretation Conclusion
Hypothesis
Predictive
May propose a method for testing the problem.
Give a justification for the method of testing.
Properties of life
Metabolism: chemical pathways that are regulated
Cellular organization
Homeostasis: maintaining stable internal environment through controlled chemical reactions or metabolism for life functions (pH, temperature, etc)
Properties of life
Reproduction: capacity to develop from juvenile to adult stage with potential to replicate own DNA
Asexual Sexual
Properties of life
Response to stimulus: able to react to external or internal changes Many responses to
stimulus are result of enzymatic proteins.
Chemical evolution of life
production of small, reduced, carbon-containing compounds like formaldehyde and hydrogen cyanide.
simple compounds reacted in the ocean to form the mid-sized molecules called sugars, amino acids, and nitrogenous bases
Chemical evolution of life
building block molecules linked together to form molecules found in cells (proteins and nucleic acids)
single molecule acquired the ability to make a copies of itself
Chemical evolution began to give way to biological evolution.
Covalent
Sharing of electrons
Stable
Forms hydrocarbons
Polar covalent bonds
Water molecule
Leads to different water properties
Ionic bonds
Hydrogen bonds
Weak individually
Strength in multiple H-bonds
Found between nucleotides
Chemical reactions
Properties of water
Slightly positive and negative “poles” of water molecule form hydrogen bonds
Frozen water molecules less dense, ice floats
Water as ideal solvent
Water as ideal solvent
Water soluble protein
Attracts water molecules
pH: water dissociation
pH scale
Homeostatic control of pH (maintaining optimal pH levels) is necessary to sustain life.
Ex: pH drop in blood = too much CO2
Organic chemistry
Alkanes: hydrocarbons with only single bonds between C and H
Alkenes: hydrocarbons with double bonds between C and H
Alkynes: hydrocarbons with triple bonds between C and H
Valence numbers
Indicates the number of bonds that can be formed.
Carbon structural molecules
Isomers
Molecules with the same molecular formula but different 3D configuration
Functional groups
Alcohol*
Aldehyde
Amine*
Carboxylic acid*
Ester
Ether
Ketone
Methyl
Phosphate*
Polymers
Most organic polymers form through dehydration synthesis.
Most break apart by hydrolysis.
Monosaccharides
Single building block of sugars (carbohydrate)
a-glucose, b-glucose, fructose
Disaccharides
Polysaccharides
Polysaccharides
Starch: plant and algae storage, product of photosynthesis (a-glucose)
Cellulose: structural polymer, product of photosynthesis (b-glucose)
Chitin
carbohydrate with an additional amine functional group that makes this molecule tough and water resistant
exoskeletons of many insects
fungal cell wall
Lipids
Ester linkage
Why is this a saturated fat?
Lipids
Energy storage
Insoluble in water
C and H
Saturated vs. Unsaturated
Lipids: What is this structure?
Lipids
What are these structures?
What proof is there that one of these structures makes up membranes?
Lipids: What is this structure?
Proteins: amino acid monomers
Proteins: amino acid monomers
Proteins
Primary conformation: peptide bonds between amino acids
Forms peptide chains
Proteins
Primary structure or conformation
Notice the amino and the carboxyl terminus (ends)
Proteins
Secondary structure: hydrogen bonds between peptide chains
Proteins
Tertiary structure: R-group interactions, depends upon properties of R group
Proteins: Quaternary structure
Protein denaturation
What can denature proteins?
How cells “fix” denatured proteins
Nucleic acids
Nucleic acids are built from monomers of nucleotides.
Nucleotides are adenine, thymine, cytosine, guanine, uracil.
Ex: DNA, RNA, ATP, and GTP
DNA structure
Notice the different types of bonds involved in the making of DNA
Nucleic acid
DNA model
Each nucleotide is made from deoxyribose sugar, phosphate, and nitrogen base.
DNA is double stranded.
Cells – 10% of test
Prokaryotic and eukaryotic cells Membranes Subcellular organizations Cell cycle and its regulation
Cell size
Viruses not cells
Bacteria, mitochondria, chloroplast all about the same size (evidence for endosymbiotic theory)
Cell fractionation
Prokaryotic cell
Surface to volume ratio Governs size
Membrane
Eukaryotic – animal cell
Eukaryotic – plant cell
Freeze fracture
Showing the “mosaic” of fluid mosaic model
Singer and Nicholson
Danielli proposed alternative model (protein-membrane-protein)
Membrane fluidity
Membrane structure
Diffusion: entropy
Osmotic balance
Guard cells, excretory system, transpiration, translocation
Osmotic balance
Sodium-potassium pump
Transport
Passive vs. active transport
Passive: osmosis
Active transport: establishing proton gradient of electron transport chain
Proton pump: auxin transport, electron transport chain
Cotransport
Translocation (phloem source to sink)
Cell cycle
Mitosis lab
500 cells = interphase = 50% 100 cells = prophase = 10% 150 cells = metaphase = 15% 150 cells = anaphase = 15% 100 cells = telophase = 10%
Mitosis
Mitosis
Binary fission
Asexual reproduction in prokaryotic cells
Other examples of asexual reproduction: budding, regeneration, vegetative propagation
Cell cycle control
Requires various checkpoints and Cdk (cyclin-dependent kinase) protein to detect levels of cyclin
Density
Density dependent cellular growth vs. density independent cancerous growth