Functional Groups
Unit 2
Unit 3
Unit 4
Unit 5
100
-OH, hydroxyl
Polar
100
Explain the difference between an acid and a base
Acid- donates a proton
Base- accepts a proton
Bonus: what is the difference between strong vs weak
100
What are the 3 type of lipids? What do they look like structurally?
Triglycerides: Glycerol + 3 fatty acid chains, “E” shape (backbone + tails), Energy storage, insulation
Phospholipids: Glycerol + 2 fatty acids + phosphate group, “Head” + 2 “tails”, Cell membrane structure
Steroids: Four fused carbon rings, Multi-ring structure, Hormones, membrane fluidity
100
Why are fatty acids better than glycogen for storing large amounts of chemical energy?
Fatty acids are better than glycogen for storing a large amount of energy as they contain more chemical bonds and hence the breaking of more chemical bonds in fatty acids generates more energy. Also, fatty acids occupy very less storage space than glycogen.
100
List three major structural differences between prokaryotic and eukaryotic cells
1. Presence of a Nucleus
Prokaryotic cells: No true nucleus — their DNA is located in an unbound region called the nucleoid.
Eukaryotic cells: Have a membrane-bound nucleus that houses the DNA.
2. Membrane-Bound Organelles
Prokaryotic cells: Lack membrane-bound organelles (e.g., mitochondria, ER, Golgi).
Eukaryotic cells: Contain many membrane-bound organelles, allowing for compartmentalization and specialized functions.
3. Cell Size and Complexity
Prokaryotic cells: ⬇️ Smaller and structurally simpler (usually 1–5 μm).
Eukaryotic cells: ⬆️ Larger and more complex (typically 10–100 μm), often part of multicellular organisms.
200
-NH2, amine
Polar, basic
200
Name the 4 main emergent properties of water
1. Moderation of temperature
2. cohesion and adhesion
3. water is a universal solvent
4. frozen water is less dense than liquid water
200
What is the structural and functional differences between alpha and beta glucose
Alpha: OH group closest to the embedded O is pointed down, starch and glycogen, used to store energy
Beta: OH group closest to the embedded O is pointed up, cellulose, plant cell walls
200
Mad cow disease is an infectious disease where one misfolded protein causes all other copies of the protein to begin misfolding. This is an example of a disease impacting ____ structure.
Tertiary
200
Briefly describe the functions of each of the organelles listed below:
-nucleus, mitochondrion, lysosome, rough ER, smooth ER, golgi apparatus, peroxisomes
nucleus: stores genetic info
mitochondria: ATP production
lysosomes: break down cellular waste
rough ER: synthesizes proteins
smooth ER: lipid synthesis
golgi apparatus: packages, modifies, distributes cellular products
peroxisomes: break down very long chain fatty acids, synthesize lipids
300
-COOH, carboxyl
Polar, acidic
300
Why does pure water have a pH of 7 even though it contains both H3O+ and OH- ions
The ions exist in equal concentrations.
300
Aquaporins are proteins embedded in the plasma membrane that allow water molecules to move between the extracellular matrix and the intracellular space. Based on its function and location, describe the key features of the protein’s shape and the chemical characteristics of its amino acids.
The top and bottom of the protein must contain charged or polar amino acids (hydrophilic) to interact with the aqueous environments. The exterior transmembrane region must contain non‐polar amino acids (hydrophobic) that can interact with the phospholipid tails. However, the inside of this channel must contain hydrophilic amino acids since they will interact with the traveling water molecule
300
What role do electrons play in dehydration synthesis and hydrolysis?
Dehydration: Electrons are shared between monomers, forming a covalent bond and creating a larger polymer as a water molecule is removed
Hydrolysis: water is added to break a covalent bond, with electrons from the water molecule forming new bonds with the released monomers, splitting the polymer into smaller units
300
Why is compartmentalization important in eukaryotic cells, and how does it enhance cellular efficiency?
Compartmentalization allows eukaryotic cells to separate and optimize different functions,
-preventing interference,
- increasing efficiency,
-and supporting greater complexity.
It’s one of the key reasons why eukaryotic cells can perform advanced and diverse functions compared to prokaryotes.
400
-SH, sulfhydryl
Polar
400
Name one biological buffer system found in the human body and describe its role
CO2+H2O↔H2CO3↔H++HCO3−
the carbonic/bicarbonate buffer system
- If the blood becomes too acidic (↑H⁺), bicarbonate (HCO₃⁻) binds with H⁺ to form carbonic acid, reducing acidity.
- If the blood becomes too basic (↓H⁺), carbonic acid dissociates to release H⁺, increasing acidity.
400
Compare and contrast the boundaries that plant, animal, and bacteria cells use to separate themselves from their surrounding environment.
All three cell types have a plasma membrane that borders the cytoplasm on its interior side. In animal cells, the exterior side of the plasma membrane is in contact with the extracellular environment. However, in plant and bacteria cells, a cell wall surrounds the outside of the plasma membrane. In plants, the cell wall is made of cellulose, while in bacteria the cell wall is made of peptidoglycan. Gram-negative bacteria also have an additional capsule made of lipopolysaccharides that surrounds their cell wall.
400
Briefly describe the design and findings of the Miller-Urey experiment and explain its significance in understanding the origin of life.
In 1953, Stanley Miller and Harold Urey simulated conditions thought to exist on the early Earth to test whether organic molecules essential for life could form spontaneously.
They created a closed system containing:
A mixture of gases thought to resemble early Earth's atmosphere: methane (CH₄), ammonia (NH₃), hydrogen (H₂), and water vapor (H₂O).
A water flask to simulate the primitive ocean.
Electric sparks to simulate lightning (a source of energy).
A cooling condenser to mimic rain, cycling the water and chemicals.
The Miller-Urey experiment showed that organic molecules like amino acids can form under conditions similar to those of early Earth, supporting the hypothesis that life could have originated through natural chemical processes.
400
In what ways are Archaea similar to bacteria? In what ways are archaea similar to eukaryotes?
Archaea are similar to bacteria in that both are single-celled organisms that lack a nucleus or membrane-bound organelles, contain a single circular chromosome, and divide by binary fission.
They are similar to eukaryotes in that they start translation with methionine, contain similar RNA polymerases, and contain DNA associated with histones.
500
-PO4, phosphate group
Polar, acidic
500
How might a buffer help prevent dangerous changes in muscle pH
Buffers help to neutralize excess hydrogen ions that build up during intense activity.
500
What are the key differences between RNA and DNA
DNA = Long-term storage of genetic information
RNA = Temporary carrier and worker for gene expression
DNA uses thymine, RNA uses uracil
DNA is double-stranded, RNA is single-stranded
500
Explain why scientists hypothesize that RNA, rather than DNA, was likely the first molecule of heredity. What properties of RNA support this idea?
Scientists believe RNA came before DNA because it could:
Store genetic information
Catalyze reactions
Possibly replicate itself
This makes RNA a strong candidate for the first molecule of heredity in the origin of life. DNA likely evolved later as a more stable storage form for genetic information, while proteins took over most catalytic functions.
500
What are the predominant proteins in each cytoskeletal element?
-Microfilaments:
-Microtubules:
-Intermediate filaments:
microfilaments: actin
microtubules: tubulin
intermediate: differ by cell type (keratin, desmin, vimentin, lamins)