Topic 2: The Chemistry of Life Flashcards
Classifying living things into groups base on:
1) nucleus presence
2) 3 main domains
1) Prokaryote: no nucleus, no membrane-bound organelles
Eukaryote: has nucleus, has membrane-bound organelles
2) 3 mains domains: bacteria, archea, eukarya
Identify and explain properties that make up living organisms or life
- Order: cell is the basic unit which then group together to form more complex and larger forms like tissues –> cell-based, complex organized
- Energy processing: at the base, photosynthesis allow plants to capture the Sun energy and turn into chemical energy in food which can then be used for functions life growth, cellular maintenance, etc.
- Sensitivity or response to stimuli: certain responses to external stimuli, can be positive or negative
- Reproduction: sexual or asexual reproduction in which DNA is duplicated and genetic information is passed on
- Growth and development: follow “instructions” coded by genes –> similar features as parents have
- Adaptation: physiology, behvaior, etc. changes to “best fit” the surrounding environment
- Evolution: mutation, random changes, natural selection, etc. result in evolution over time –> diversification of species on Earth
https://courses.lumenlearning.com/wm-biology2/chapter/properties-of-life/
What element is life based on?
In what ways does it bond with itself and other elements?
How does it act in covalent bonds?
Carbon-based
Able to form bonds in different ways and directions, giving various 3D shapes
“Sweet spot for stability” - stable but not too stable in forming covalent bonds
Describe charge, hydrophobicity and polarity of C, O, N, P and H
- C: neutral, non-polar, hydrophobic
- O,N,P: tend to make compounds polar, hydrophilic
+ partly (dipoles) or fully charged (polar) - H:
+ near C/H: neutral
+ near O/N: polar
Describe the polarity of water and explain why
Water is polar molecule as O when bonded with H still has 2 lone pairs of electrons, so it pulls the electrons towards itself making it slightly + and H become slightly -
Explain how water helps to stabilize temperature and its insulation function as ice
- Freezing water releases energy and melting water captures energy
- Good evaporative cooling: as water evaporates from the surface of an object, it helps to cool the surface
- Ice floats and acts as an insulation layer, so the underneath water is warmer.
What is the basic unit of carbohydrates/sugars/sacchrides and what is it composed of?
What is its structure?
What are some more complex forms? Give examples
- Monosacchrides: made up of C, H, O
+ more O means very polar
+ has ring structure - Disacchrides: 2 monosacchrides connected in different ways
- Sugar polymers: long chains of monosacchrides (starch, cellulose, chitin, bacteria cell walls
Classify 2 types of lipids and the form it is more likely to be found in and why
- Saturated: all single bonds forming long, straight chain
–> can be packed together nicely –> solids - Unsaturated: has 1 or more double bonds
–> bent, cannot be packed as nicely –> liquids
Describe some properties of lipids and give some examples of lipids
- Poorly soluable in water
- Soluable in organic (hydrophobic) solvents
- High proportions of C/H
- Fats, oils, waxes, steroids
Describe some functions of lipids
- Energy storage (triglycerols - store glucose)
- Molecular signal (steroids - estrogen, testosteron)
- Protection and waterproofing (waxes)
- Structure and barriers (phospholipid bilayers as cell membrane)
Amino acids are building blocks of ??
What are 2 groups that are present in an amino acid and are they charged or not?
Proteins
Have amino group (-NH2) and carboyxylic group (-COOH) which are charged in aqueous solutions (-NH3+ and -COO-)
Describe the role of size, charge and polarity in shape and function of amino acids
Depending on the side chain group, the amino acids have different sizes, charges, and polarity which result in different shapes and make the protein be responsiable for different functions.
What is building blocks of nucleic acids?
Identify the components of that building block
Nucleotides, consisting of
+ a phosphate group
+ a sugar (ribose or deoxyribose)
+ a nucleobase (A,G,C,T, or U)
Identify 3 types of nucleotide
Mono-, di-, and tri-nucleotide (1,2 or 3 phosphate group)
Explain capillary action and what is special about it
Ability of liquid to flow in narrow spaces, even against gravity
