60% multiple choice 40% free response AP Biology Exam Review 60% multiple choice 40% free response

Organizing life Atoms Molecules Organelles Cells Tissues Organs Systems Organism species Population Community Ecosystem

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

Nucleic acid DNA structure Notice the different types of bonds involved in the making of DNA

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