C5 Chemistry of Life Flashcards
organic vs inorganic
- organic: carbon based compounds, larger and more complex
- inorganic: not carbon based, simpler/smaller
organic chemistry
chemistry of carbon compounds within living things
- other important elements include: O2, H, N, P
State the 4 components essential for life.
- water
- minerals
- vitamins
- biomolecules
Describe how water is essential for life.
- water makes up the greatest % of the body
- universal solvent
- an important medium for reactions
- has a low viscosity = a transport medium (can move easily through small spaces/allow small substances to move through)
- benefits to plants: support/rigour, adhesive + cohesive properties
Briefly outline what vitamins and minerals are, the two types, and how they are essential for life.
- inorganic ions
- make up many biomolecules
- aid key biological processes
Macronutrients: elements needed in large quantities
Micronutrients: elements needed in small quantities
- not having enough = deficiencies
What are vitamins?
What are the two types
VITAMINS
- around 13 essential for health
- all except VD must be obtained externally (food)
TWO TYPES
- fat soluable (dissolves in fat)
- water soluable (dissolved in water)
polymers vs monomers
- monomers: smaller molecules/building blocks
- polymers: larger molecules, subcomponents of monomers
State the four categories of bio/macromolecules needed for life, and their corresponding monomer.
- carbs (monosaccharides)
- lipids (fatty acids + glycerol)
- proteins (amino acids)
- nucleic acids (nucleotides)
metabolism
- the sum total of all enzyme-catalysed chemical reactions that occur within the body
- includes catabolism and anabolism
catabolism vs anabolism
Catabolism
- decomposition
- polymers break down to monomers
- releases energy
- includes hydrolysis
Anabolism
- synthesis
- uses energy
- monomers built up to polymers
- includes condensation reactions
CARBS - biomolecule
- consist of… and their ratio
- monomers (…two? multiple?)
MONOMER
- what are they
- main functions (2)
- provide examples (2)
POLYMER
- main functions (2)
- provide examples (3)
- Consist of: C, H, O (1:2:1 ratio)
- Monomer: monosaccharides (2 = disaccharide)
- Polymer: polysaccharide
MONOSACCHARIDES (monomer)
- single sugar molecules
Functions: an energy source for cell metabolism, structural component for polysaccharides
- glucose, ribose
POLYSACCHARIDES (polymer)
- Functions: energy storage, structural support for plants
- cellulose, starch, glycogen
glucose
- monosaccharide
- source of energy for CR (energy released helps ATP production)
- produced by Phs
- animals cannot make, must consume it (or break down polysaccharides)
ribose
- monosaccharide
- drives synthesis of RNA, DNA and ATP
cellulose
structural support in plant cells
- polysaccharide
- not easily broken down (humans cannot)
starch
glucose storage in plants
- polysaccharide
- found in seeds and plant roots
- easily broken down by enzymes
glycogen
SHORT term storage of sugar in animals
- polysaccharide
- if blood glucose levels drop, glycogen is broken down to release glucose for energy
- located in the liver + skeletal muscles
LIPIDS - biomolecule
- consist of… and their ratio
- monomers (2)
- key qualities (2)
- main functions (3)
- types (2)
- what is the polymer, and what does it consist of?
- Consist of: C, H, O (no set ratio, but greater than 2:1 of H:O)
- Monomers: fatty acids + glycerol
- Qualities: hydrophobic, relatively insoluble
- Functions: long term energy store, body insulation, aid micronutrient absorption
- Two types: fats/waxes (solid room temp) + oils (liquids room temp)
TRIGLYCERIDES (polymer)
- Consist of: 1x glycerol, 3x FAC
saturated vs unsaturated fats
- fats are a type of lipid
Saturated
- the fatty acid chains are saturated with H
- the greatest number of H possible
- no double bonds
Unsaturated
- one or more double bonds (look like bends/kinks in the fatty acid chain)
relative insolubility
- how lipids are important due to this (3)
Lipids are insoluble:
- fats are nonpolar (have no + or - regions)
- water is polar (has + and - regions)
- lipids attracted to lipids, H2O attracted to H2O = they never mix
Important role in:
- maintaining osmotic balance
- formation of cell membranes
- providing protective, hydrophobic coating (hair, skin, feathers, leaves)
essential fatty acids
- functions (3)
- example
- essential to body, but we must ingest (cannot produce)
- Functions: cell membrane structure, gene transcription, energy sources
- e.g. omega-3
phospholipids
- what?
- consist of?
- qualities (2)
- main function
- a specialised type of lipid (not true fats)
- 1x glycerol, 2x FAC, 1x phosphate group
- are amphipathic (hydrophilic head + hydrophobic tail)
PROTEINS - biomolecule
- consist of?
- monomer
- polymer
MONOMER
- how many types?
- describe the structure
- describe how polymer is formed
PROTEIN STRUCTURE (4)
- describe
PROTEIN TYPES (2)
- describe
- functions
- examples
- Consist of: C, H, O, N
- Monomer: amino acids
- Polymer: polypeptide chains
AMINO ACIDS
- 20 different types
Structure
- central C atom, attached to:
- R group
- carboxyl group (COOH)
- amino group (NH2)
- hydrogen atom (H)
- AAs join together to form a dipeptide + H2O
- this bond is called a peptide bond
- multiple AAs binding together form a polypeptide chain (polymer)
- these fold up to form proteins
PROTEIN STRUCTURE
- Primary: a linear sequence of AAs (a PP chain)
- Secondary: the PP chain twists into a repetitive structure (double helix)
- Tertiary: PP chain folds into a more complex, 3D shape
- Quaternary: multiple PP chains join together to form a protein
PROTEIN TYPES
Fibrous
- long narrow strands
- secondary structure
- Functions: support, structure, movement
- they ARE something (keratin in hair/nails, elastin in skin)
Globular
- compact + rounded
- tertiary structure
- Functions: controls/assists biological functions
- they DO something (haemoglobin, enzymes, antibodies)
denaturing
a structural change in a protein that results in the loss of its biological properties
- AS of enzyme changes shape
- no longer compatible to specific substrate(s)
- reaction doesn’t occur
- can be reversible or permanent
- Caused by: temp, pH change, chemicals
NUCLEIC ACIDS - biomolecule
- consist of?
- monomer
- polymers (2)
MONOMER
- made up of?
- describe structure
POLYMERS
- functions of each
- Consist of: C, H, O, N, P
- Monomer: nucelotides
- Polymers: DNA + RNA
NUCLEOTIDES (monomer)
- Made up of: 5 carbon-pentose sugar (ribose/deoxyribose), phosphate group, nitrogenous base (A/G/C/T/U)
- sugar in middle, base + phosphate attached to either side
DNA/RNA (polymers)
- DNA function: carry/contain all genetic information in all cells
- RNA function: transfer specific genes outside the nucleus to synthesise proteins
Describe the 3 differences between DNA + RNA.
DNA
- deoxyribose sugar
- adenine, guanine, cytosine, thymine
- double stranded
RNA
- ribose sugar
- adenine, guanine, cytosine, uracil
- single stranded
enzymes
- what
- structure
- biological catalyst (lower the activation energy for the body’s chemical reactions
- they facilitate, speed up + control reactions
- not a reactant: are unchanged after reaction and can be used again
STRUCTURE
- globular proteins
- many unique enzymes, each with a specific active site (AS)
- AS of an enzyme has a specific complementary shape to a specific substrate (reactant)
Describe the model that best describes how enzymes bind to a substrate.
INDUCED FIT MODEL
- can be either anabolic reactions or catabolic reactions
1. The substrate bonds to the enzyme’s active site.
2. AS changes to become more complementary to the substrate, forming the enzyme-substrate complex (ESC)
3. The reaction occurs (anabolic/catabolic), products are released
Describe the two types of reaction that enzymes facilitate.
- Catabolic: polymers to monomers
- Anabolic: monomers to polymers
Describe the factor affecting the rate of an enzyme-facilitated reaction.
TEMP
- each enzyme has an optimum (37°C for humans)
- Lower: slower ROR = less KE = less reactions
- Higher: enzyme denatures (AS changes shape)
- graph will increase to optimum, then rapidly decrease (denaturing)
pH
- each enzyme has an optimum pH depending on where it functions in the body (e.g. stomach = pH 2)
- graph will increase to optimum, then rapidly decrease (denaturing)
Substrate
- substrate conc increases = ROR increases
- limited by enzyme conc
- graph will increase then plateau
Enzyme
- enzyme conc increases = ROR increases
- limited by substrate conc
- graph will increase then plateau
Describe the factors that assist or inhibit enzyme activity.
ASSISTING
Cofactors
- inorganic molecules that bond with the allosteric site of an enzyme
- changes shape of the AS to be more complementary to the substrate
Co-enzymes/co-substrates
- organic molecules that bond with the AS
- help substrate bond faster to enzyme
INHIBITING
Competitive
- molecule bonds to the AS, preventing the substrate from bonding
- reaction cannot occur
Non-competitive
- molecule bonds to the allosteric site, changing the shape of the AS
- substrate cannot bond, reaction cannot occur
allosteric site
another site on an enzyme, seperate from the active site, that molecules are able to bond to
- can be used for assisting or inhibiting enzyme activity
cellular respiration
- what
- word equation
the controlled release of energy from organic compounds (glucose, usually) in cells to form ATP
- glucose + oxygen = carbon dioxide + water + ATP
ATP
- what
- structure
- how does it work
Adenosine Triphosphate
- type of nucleic acid: adenine base, ribose sugar, 3 phosphate groups
- is a high energy molecule and an immediate power source for cell processes
HOW
- ATP releases energy via being hydrolysed (a cycle)
- the third phosphate is held by an unstable bond, when it is released, it releases energy
- results in ADP (Di) and Pi (the released phosphate)
- ADP = low battery, energy used
- can then be regenerated by adding Pi to form ATP again
- ATP = full battery, energy ready to be released
anaerobic vs aerobic respiration
- what
- where
- which occurs when?
ANAEROBIC
- absence of O2
- partial breakdown of glucose
- in the cytosol
- small yield of ATP (2) from glycolysis
AEROBIC
- presence of O2
- complete breakdown of glucose
- in the mitochondria
- large yield of ATP (30-38)
- aerobic is far more efficient
- anaerobic is essential when the body is not able to get enough O2 to all cells (e.g. heavy exercise)
Outline/summarise the stages of cellular respiration (like a flow chart):
- what occurs
- where it occurs
- net ATP yield
GLUCOSE
|
Glycolysis (cytoplasm)
- 2 ATP
|
PYRUVATE
|
If O2 not present:
Anaerobic CR (cytoplasm)
- no more ATP produced
- fermentation
TOTAL: 2 ATP
|
If O2 present:
Aerobic CR (mitochondria)
- 30-34 ATP
TOTAL: 30-38 ATP
CELLULAR RESPIRATION
Describe the process of glycolysis:
- where it occurs
- when it occurs
- total yield (products + ATP)
GLYCOLYSIS
- in cytoplasm
- starting process of both AN + AE resp
Glucose is broken down into:
- 2x pyruvate
- 2x NADH (a co-enzyme needed for AE resp)
- 2x ATP
CELLULAR RESPIRATION
Describe the process of AE resp:
- where it occurs
- when it occurs
- process steps
- total yield (products + ATP)
AE RESP
- in mitochondria
- when O2 is present
Process:
- link reaction
- Krebs cycle
- electron transport chain
Pyruvate converted to:
- CO2
- H2O
- (ideally) 34-36 ATP
NET YIELD: 30-38 ATP (glycolysis + AE resp)
CELLULAR RESPIRATION
Describe the process of AN resp:
- where it occurs
- when it occurs
- fermentation (purpose, products and cycle process)
- total yield (ATP)
AN RESP
- in cytoplasm
- when O2 is absent (body cannot get to cells fast enough)
FERMENTATION
Why
- body cannot get O2 to cells fast enough, all stored ATP is used up, but energy is needed
- AN resp restores NAD+ (needed in glycolysis reaction to convert to NADH)
- the fermentation cycle allows glycolysis to continue to produce ATP in a low O2 environment
Pyruvate (from glycolysis) converted to:
- Animals: lactic acid (lactate)
- Bacteria/yeast: ethanol + CO2
Process
- is a reversible cycle
- once O2 is present, lactic acid/ethanol is converted back to pyruvate
- AE then continues as normal
TOTAL YIELD: 2 ATP (glycolysis)
PHOTOSYNTHESIS
- state equation
- describe 2 stages: name, process, equation
- carbon dioxide + water = glucose + oxygen
STAGE 1: Light Dependent
- Process: photolysis
- chlorophyll absorbs photon (light E) from the sun, excites H2O electrons, they become delocalised
- chlorophyll takes an electron from H2O molecule, SPLITTING it into H2 (used in Stage 2), O2 (waste), + producing ATP
- photon - chlorophyll - ATP + H2 (+ O2 waste)
STAGE 2: Light Independent
- Process: carbon fixation
- H2 + ATP (from S1) + CO2 (from air) react to produce glucose
Describe the structure of the leaf referring to the important components (6).
- waxy cuticle: top + bottom of leaf
- upper epidermis: transparent, allowing max light penetration for max Phs rate
- palisade mesophyll: contains chloroplasts which contain chlorophyll, the main photosynthetic pigment
- vascular bundle: xylem delivers H2O to cells for Phs, phloem transports glucose produced from Phs
- spongy mesophyll: spaced out for gas exchange
- stomata (pores): controlled by guard cells, facilitate GE (CO2 in, O2 out)
Describe ways of measuring the rate of Phs (directly/indirectly).
DIRECTLY
- production of O2 (e.g. count bubbles produced by water plants)
- uptake of CO2 (e.g. enviro pH increase)
INDIRECTLY
- increase in biomass (total mass of plant)
State the limiting factors of Phs and describe the shape of the graph when rate of Phs is on the Y axis.
TEMP
- increase in temp = more KE = more frequent collisions = higher rate of Phs
- graph has increase, then optimum, then decrease due to denaturing
LIGHT INTENSITY
- increase in light = more energy to drive reaction = higher Phs rate
- graph will increase then plateau when chloroplasts are working at max efficiency
CO2 CONC
- increase in CO2 = more substrate = higher Phs rate
- graph will increase then plateau due to another limiting factor
PHS VS CR
- the reactions are complementary
- products vs inputs
- state equations for both
- differences
- similarities
- complementary reactions within the environment
- products of Phs are inputs of CR, vice versa
- PHS: CO2 + H2O = C6H12O6 + O2
- CR: O2 + C6H12O6 = H2O + CO2
DIFFERENCES
- Phs: anabolic, synthesises/builds glucose
- CR: catabolic, breaks down glucose
- producers perform both, consumers perform just CR
SIMILARITIES
- both involve ATP production
- Phs: ATP produced via light energy, used to make glucose
- CR: ATP produced via breakdown of glucose
- both require enzymes to complete the reaction
COMPENSATION POINT GRAPHS
- what are they used to measure
- what do they show
- what is a comp point, when do they occur
- what does above/below a comp point represent
- describe how CR/Phs depends on time of day
- used to measure O2/glucose production, CO2/H2O use
- demonstrates the relationship between CR + Phs (time of day/light on X axis, glucose/carb production on Y axis)
- COMP POINT: when what is produced by Phs = what is used by CR (no excess), Phs rate = CR rate, usually occur at dusk/dawn
- ABOVE CP: plant is producing more glucose then it is using
- BELOW CP: plant is using more glucose than it is producing
TIME OF DAY
- rate of Phs is dependent (due to light availability)
- highest rate is at midday
- rate of CR is not dependent
- rate remains relatively stable throughout day
- goes up slightly when Phs increases, as needs small amount of ATP to start up
DNA
- role of DNA
- name complementary base pairs + bonds
- sugar phosphate backbone structure + function
- double helix: how is it formed
REPLICATION
- 2 stages, enzyme involved + process
- the entire process is…
- Role of DNA: contains/carries all genetic information/genes for all cells
- A + T (double H bond), G + C (triple H bond)
BACKBONE
- sugar phosphate backbone formed by the phosphates/sugars of nucleotides bonding to form a polynucleotide (polymer)
- function: provide support + protection to N bases
DOUBLE HELIX
- caused by antiparallel strands (strands run in opposite directions)
- causes twisting of strands to form an energy stable structure (the helix)
- a fold occurs every 10-15 base pairs
REPLICATION
Stage 1
- Helicase enzyme moves along helix and unwinds DNA strands
- each parent strand is a template for a new complementary daughter strand
Stage 2
- DNA polymerase enzyme synthesises both new strands
- the strands have complementary bases to parent strands
- both stages happen at once
- the process is semi-conservative (uses half of already formed material, half is created)
PROTEIN SYNTHESIS
- why?
- stages (2), their location, + process
WHY
- DNA is too large and unstable to leave the nucleus
- protein synthesis allows for singular genes to be transferred outside the nucleus, using mRNA, for a protein to be made
TRANSCRIPTION
- in nucleus
- DNA is unwound at the location of the specific gene
- a complementary strand of mRNA is made (U instead of T)
- after it is formed, exits nucleus via a nuclear pore
TRANSLATION
- in cytoplasm
- mRNA binds to a ribosome
- ribosome translates mRNA one codon at a time
- tRNA (transport) with complementary anti-codons (same as og DNA gene, but with U) drops off the specific AA that corresponds to the codon
- the AAs bond together to form a PP chain
- after entire mRNA strand is translated, the PP chain is formed
codon
3 bases, a set
- code for a specific AA
- translated together by a ribosome during protein synthesis
mRNA
messenger RNA
- a smaller, more stable nucleic acid used to transfer specific genes outside the nucleus during protein synthesis
tRNA
transport RNA
- a T shaped RNA molecule
- has anticodons to the mRNA strand
- brings a specific AA for each codon to form the PP chain
GENE (POINT) MUTATIONS
- define
- ways they can occur (4)
- types of effects (4)
- define degenerate
- a change in a single nucleotide in the DNA code, leading to a gene mutation
WAYS
- Substitution: base is replaced with a different one (ATG to ACG)
- Inversion: two bases next to each other swap places (ATG to AGT)
- Insertion: base is added in
- Deletion: base is deleted
EFFECTS
- Missense mutation: mutation alters a single AA, leading to genetic variation, not always bad
- Nonsense mutation: mutation causes a premature stop codon, PP chain is incomplete and dysfunctional, usually bad
- Frameshift mutation: insertion/deletion shifts the entire DNA strand, PP chain is dysfunctional, usually very bad
- Silent mutation: base changes but still codes for correct AA, no effect (this is possible as the DNA code = degenerate: alternate substances can perform the same function)
