Biology Exam

Parts of RNA nucleotides

RNA Sugar: Ribose

RNA Bases: A, U, C, G

Parts of DNA nucleotides

DNA Sugar: Deoxyribose

DNA Bases: A, T, C, G

Describe features of Macromolecules

• Large complex structures

• Polymers made up of monomers

• Essential for life (carbohydrates, lipids, proteins, nucleic acids)

Monomers

Simple building blocks of polymers (e.g., amino acids, monosaccharides)

Polymers

Large molecules formed by the joining of monomers (e.g., proteins, polysaccharides)

Functions of Macromolecules

• Carbohydrates: energy storage and structural support

• Lipids: energy storage, insulation, and cell membrane structure

• Proteins: enzymes, structural components, and transport

• Nucleic Acids: store and transmit genetic information

Lipids

• Hydrophobic molecules including fats, oils, and waxes

• Made of hydrocarbon chains and rings

Examples of Lipids

• Triglycerides (fats and oils)

• Phospholipids (cell membranes)

• Steroids (hormones)

Proteins

• Polymers made of amino acids

• Amino acids linked by peptide bonds

Protein is a polymer or a chain of sub units

a) what is the sub unit of a polymer

b) what kind of bond links these sub units together

Sugars

• Carbohydrates including monosaccharides (glucose, fructose) and disaccharides (sucrose, lactose)

• Used for energy storage and structural components

Nucleic Acids

• Polymers made of nucleotides (DNA and RNA)

• Store and transmit genetic information

How to Identify a Compound as Ionic or Covalent

Ionic: Metal + Non-metal (transfer of electrons) → e.g., NaCl

Covalent: Two non-metals (sharing of electron) → e.g., H2O

Use examples of ionic, covalent, and polar covalent bonds to help explain how they are different

Describe examples of different Chemical Reactions

• Synthesis: A + B → AB

• Decomposition: AB → A + B

• Single Replacement: A + BC → AC + B

• Double Replacement: AB + CD → AD + CB

Give Examples of Chemical Reactions

• Dehydration Synthesis: monomers join to form polymers by removing water

• Hydrolysis: polymers break down into monomers by adding water

• Neutralization: acid + base → salt + water

• Redox: transfer of electrons

Describe how an Enzyme works

• Enzymes lower activation energy

• Substrate binds to active site

  • Lock and key or induced fit

• Enzyme remains unchanged, product is released

How is an enzyme shape important to the enzyme-substrate complex

What is a functional group? State 2 characteristics of a functional group that make it important to biological systems

Identify the different Functional Groups

• Hydroxyl (-OH)

• Carboxyl (-COOH)

• Amino (-NH2)

• Phosphate (-PO4)

• Methyl (-CH3)

Identify the functional group involved in the condensation reaction that forms the long chains of glucose molecules that form starch?

Functions of Functional Groups

• Hydroxyl: polar, forms hydrogen bonds

• Carboxyl: acidic

• Amino: basic

• Phosphate: energy transfer (ATP)

• Methyl: gene expression

Difference of Hydrophobic and Hydrophilic

HydroPHILIC = likes water

HydroPHOBIC = repels water

Provide an example of both Hydrophilic and Hydrophobic

Difference between Hypertonic, Hypotonic and Isotonic

Hypertonic = water moves out of the cell

Hypotonic = water moves into the cell

Isotonic = no net change → remains the same

Difference between Anabolic and Catabolic

Anabolic = build molecules (requires energy)

Catabolic = break molecules (releases energy)

Difference Between Deoxyribose (DNA) and Ribose (RNA)

DNA → no OH (hydroxyl group) on 2' carbon

RNA → has OH (hydroxyl group) on 2' carbon

Difference between Purine and Pyrimidine

Purines = A, G (adenine, guanine) → two rings

Pyrimidines = C, T, U (cytosine, thymine, uracil) → one ring

Difference between 3’ and 5’ ends of DNA

3’ end: has a hydroxyl (-OH) group on the 3' carbon of deoxyribose

5’ end: has a phosphate group attached to the 5' carbon of deoxyribose

Difference between Leading and Lagging Strand

Leading = continuous replication

Lagging = replicated in Okazaki Fragments

Difference between Nonsense and Missense Mutations

Nonsense = Stop codon appears early

Missense = Wrong Amino Acid inserted

Difference between Substitution, Insertion, Deletion and Frameshift Mutations

Substitution = Base swap

Insertion = add base(s)

Deletion = remove base(s)

Frameshift = caused by insertion and/or deletion, alters reading frame

Difference between Introns and Exons

Introns = non-coding regions (removed during splicing)

Exons = Coding regions (expressed)

Difference between mRNA, tRNA and rRNA

• mRNA = messenger RNA: carries genetic code from DNA to ribosome

• tRNA = transfer RNA: brings amino acids to the ribosome

• rRNA = ribosomal RNA: forms part of the ribosome

Difference between -70mV and +30mV

-70mV = resting membrane potential

+30mV = Peak Action Potential (depolarization)

Difference between Autonomic and Somatic Nervous Systems

Autonomic = involuntary nervous system (e.g., heart rate, digestion)

Somatic = Voluntary nervous system (e.g., muscle movement)

Difference between Insulin and Glucagon

Insulin = lowers blood glucose levels

Glucagon = Raises blood glucose levels

Nucleus

Contains DNA; control center of the cell

Ribosome

Site of protein synthesis

ER (rough vs smooth)

Rough ER = Protein processing and synthesis

Smooth ER = Lipid processing and synthesis

Golgi Apparatus

Modifies, sorts, and packages proteins for secretion or transport

Mitochondria

Site of cellular respiration; produces ATP

Chloroplast

Site of photosynthesis in plant cells

Lysosome

Contains digestive enzymes for breaking down cellular waste

Vacuole

Storage of water, nutrients, and waste

Plasma membrane

Selective barrier controlling entry and exit of substances

Transport Types: Passive vs Active

• Passive: Diffusion, osmosis, facilitated diffusion (no energy required)

• Active: Requires ATP → pumps, endocytosis, and exocytosis

Fluid Mosaic Model

• Phospholipid bilayer with embedded proteins

• Cholesterol = maintains fluidity

• Carbohydrates = cell identification tags

Protein Structure

• Primary: Amino acid sequence

• Secondary: Alpha-helix, Beta-sheet (local folding patterns)

• Tertiary: 3D folding (overall shape)

• Quaternary: multiple polypeptide chains

Mitochondria and Chloroplast Function

Mitochondria: inner membrane (ETC), matrix (Krebs cycle)

Chloroplast: thylakoid (light reactions), stroma (Calvin cycle)

Cellular respiration stages

• Glycolysis

• Krebs Cycle (Citric Acid Cycle)

• Electron Transport Chain (ETC)

Products at each stage of Cellular Respiration

• Glycolysis → 2 ATP, 2 NADH, 2 pyruvate

• Krebs Cycle → 2 ATP, NADH, FADH2, CO2

• ETC → 32-34 ATP, H2O

What is the purpose of glycolysis?

How is NAD+ important to glycolysis?

How is ATP important to start glycolysis

Locations of cellular respiration

• Glycolysis → Cytoplasm

• Krebs Cycle → Mitochondrial Matrix

• ETC → Inner Mitochondrial Membrane

Describe how the Electron Transport Chain (ETC) works

• Uses NADH/FADH2 to pump H+ ions across inner mitochondrial membrane

• H+ gradient drives ATP synthase to produce ATP

• Final electron acceptor = O2, forming H2O

What are the 4 steps of aerobic cellular respiration?

Which one of those steps act on glucose

Which of the 4 happen in the mitochondria

Where is pyruvate produced?

How is NADH formed during glycolysis

Where in the mitochondrion does kerbs cycle take place?

Acetylene Co-A is produced by the translation reaction. What happens to each part?

What is meant by the term decarbonxylation

List key product of the Krebs cycle

What are the roles of NADH and FADH2 in the mitochondrion

What is chemiomosis? Where does it take place

• Where is the high concentration of hydrogen ins located in the mitochondrion

• How did the hydrogen ions get there

List the products of the photo reaction in photosynthesis. Which products participate in synthesis reactions

• what is the product of the Calvin cycle

Make a chart listing the major macromolecules, an example for each, and a list of the functional groups that are characteristics of each macromolecule

Where does the light dependant reactions take place

What is photolysis and why is it important for photosynthesis

Make diagram of the celll showing membrane, nucleus, cytoskeleton and at least one mitochondrion. Use one colour to show the path of one molecule of glucose into the cell, through glycolysis and into the mitochondrion for respiration. Use a second colour to show where energy is used to drive cellular respiration. Use a third to show where energy is stored by cellular respiration

Makes a diagram of a mitochondrion and chloroplast. Indicate which reaction take place on membrane and which reaction take place dissolved in solution. Indicate how the following molecules move between two organelles: glucose, CO2, O2, H2O

Give examples of each of these reactions:

• hydrolysis

• Condensation

• Neutralization

Give an example of an oxidation reduction reaction. Identify which reactant is more electronegative than the other

Use structural formulas to draw one polar molecule and one non-polar molecule. Explain how the bonding electrons contribute to the polar and non-polar nature of the molecules

Describe the role of the skin in maintaining homeostasis in the body

Draw the shape of a nephron found in human kidney tissue. Label the four major sections of the nephron

On the diagram drawn, show wher the following processes occur

• glomerular filtration

• Glucose leaves the filtrate

• Water leaves the nephron

• Salt ions removed from the nephron

• Urea diffuses out of the nephron

Draw a negative feedback loop that illustrates how beta cells regulate glucose blood sugar levels

Make a diagram of a neuron and label it

Referring to the diagram, show where each of these ions is concentrated for a neuron at rest:

• Na+

• K+

• Cl-

• And other ions

The phospholipid layer bilateral is not very permeable to ions. How can ions diffuse into or out of a nerve cell

Explain what is meant by resting potential

Describe the role of the Na+/Ka+ pump in restoring resting potential of a nerve cell membrane following a nerve impulse

Compare the way steroid and non-steroid hormones affect cellular activity

Identify the organs that produce sex hormones in males and females. List the hormones produced by each structure

Name the products of each stage of Photosynthesis

Light Reaction → Products: O2, ATP, and NADPH

Calvin Cycle → Products: Glucose (from CO2 using ATP/NADPH)

Label key structures of a chloroplast

where each stage of photosynthesis happen

Light Reaction → Location: Thylakoid Membrane

Calvin Cycle → Location: Stroma

List the three stages of the Calvin cycle. For each stage, identify the energy input and the products

Explain how plants capture solar energy.

Why does the photosystem 680 provide some adaptive advantages over photosystem 700?

Write an equation to summarize the photo reaction of photosynthesis

How does polarity of water molecules account for the ability of water to dissolve many substances

• What is a hydrogen bond?

• Identify one case where hydrogen bonds are important in a biological system