Molecular & Cellular Reveiw Flashcards
What are carbohydrate important in plants?
For energy, structure support, and storage
Starch fx
storage, then when needed can break down using amylose enzyme to make glucose (energy)
Hydrolysis
process where a certain enzyme breaks down the carbohydrate into glucose
How does starch break down into glucose?
Since starch is a disaccharide, it needs to break apart - it does this by hydrolysis
Cellulose fx
structural support of cell walls, can also be broken down by cellulase to form glucose but this isn’t the primary fx
How do plants make carbohydrates?
through photosynthesis
What is the process where carbohydrates get broken down into glucose called?
Respiration
Chitin
cell wall of fungi is made out of this, tough to digest making fungi harder to eat than grass
What is the cell wall of plants compared to fungi made out of?
Plants CW: cellulose
Fungi CW: chitin
What happens when plants dont have enough glucose to use as energy?
they will break down amino acids to glucose, but they will mainly produce glucose through photosynthesis.
What has to happen to chitin for it to be useable for the cell wall?
Chitin gets broken down by chitinase into individual molecules since its a polysaccharide
Peptide Bonds
covalently bonds amino acids together to form proteins
Proteins
chains of amino acids
What are the purpose of peptide bonds?
to form different proteins
Lipids in plants
energy reserve, mostly found in seeds
Importance of protein structure (primary, secondary, etc)?
determines proteins functions
What can lipids in plants be broken down into?
Fatty acids
Importance of fatty acids in plants
major storage form of energy
Two types of fatty acids
saturated and unsaturated
Importance of saturated/unsaturated fatty acids in plants?
they can burn into energy for the plant when there is no glucose available
Saturated fatty acids
no double bonds = tightly packed = solid fats in seeds
ex: sesame seed oil, pumpkin seed oil
Unsaturated fatty acids
double bonds = spread out producing twists in the chain = liquid fats like oils, plants don’t store a lot of this
Subrin
rubber, waxy material, found in bark/roots to keep water in
Quitin
surface wax, found outside cell membrane, apples/leaves
Lignin
a hardening agent, typically found in wood/bark, used like filling/calcking gaps and hardens to protect modified carbohydrate, used for structure and support
thermodynamics
study of energy
two laws of thermodynamics
- energy cannot be created/destroyed but it can change forms and give off energy (waste) as heat
- Entropy is always increasing overall in the universe (disorder)
-vital in production of ATP
Joseph Priestley
discovered oxygen
experiments with clear jars
Joseph Priestley experiements
put plants inside a jar, then put mice in other jar = plants survive, mouse dies
put mouse in with plant = mouse and plant survive
turn off light = both die
What type of lipid are fatty acids?
triglycerides (unit of fat)
Waxes in plants
on surface of ALL plants and in bark/roots
used to keep water in, NOT out
examples of waxes in plants
suberin, Quinton, lignin
symplast
living stuff, inside the cell
apoplast
outside the cell, non living
ex: cell wall
middle lamella
has pectin, line where cells come together
pectin
holds cells together, contains calcium
paired pits
holes in cells
plasmodesmata
channel between the two cells
-allows for movement
plastids
main site of photosynthesis, storage, pigment synthesis
store food as starch
what plastid is responsible for storing starch
leukoplastid (amyloplast)
what plastid is where photosynthesis happens
chloroplast
central vacuole
storage, hold water for when plant needs it
biggest structure in plant cell
tonoplasts
membrane around the central vacuole, regulate movement in/out
what is the movement of water called
osmosis
turgor pressure
helps with structure support in non woody plants
why is the second law of thermodynamics vital in plants?
2nd law: entropy is always increasing overall in the universe, this is what drives the proton gradient and therefore creating ATP
Jan Baptist van Helmet
will tree experiment (1600s)
- watered tree for 5 yrs noticed it gained weight but soil still weighed the same
- proved tree mass was coming from the water not the soil (trees NOT eating soil)
- leads to early insight on photosynthesis
Wave Particle Theory
1800s, shows that little things like electron and photons can act as waves or particle like
how are energy and wavelength related and what does that mean?
they are inversely proportional, meaning if one increases the other decreases
why is the relation between energy and wavelength crucial in the wave-particle theory ?
helps us understand the behavior of waves and how photons move in a wave pattern
how are electrons excited in light reactions of photosynthesis?
by the sun, the outer e- gets hit by sunlight and gets excited
Quantum leaping and why electrons do this?
electrons do this whenever they absorb or release energy bc they have to be in a certain place (aka certain step on the staircase)
why is quantum leaping important?
important for atoms to absorb and emit light so we can see the world in color
pigments in plants
chlorophyll A: photosynthetic pigment, membrane-bound in chloroplast
Chlorophyll B, and carotenoids (xanthophyll & carotene): accessory pigments, that absorb energy and pass it to “A”
what are all the pigments together known as?
light-harvesting complex
inductive resonance
process where energy is sent from pigment to pigment, ultimately to get to chlorophyll A
structure of chlorophyll
phytol tail
porphyrin head - central green Mg atom, makes chlorophyll green
Phycobilin
not in higher plants, use phycobilin to absorb light, usually in plants with shortage of light
Phycoerythrin
absorbs blue/green, reflect red
Phycocyanin
absorbs red/orange, reflects blue
