-some notes from early semester 2 are not on here
Embryonic Plants:
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Embryonic plant forms as part of a seed. The embryonic shoot is separated from the
embryonic root (radicle) by a section of stem.
Seeds contain starch to get the seed going. (Starch = glucose that is lined together like
legos).
Germination:
○ Germinations when the first part of the embryo (the radicle) breaks out of the
seed coat.
○ Mainly, Germination is triggered when water seeps into the seed, but can trigger
from abrasion,freezing bright light, fire.
○ Water activates enzymes in endosperm, which break down stored starches into
sugars (glucose)
■ Cells in the embryo use sugar and oxygen for aerobic respiration as the
embryonic plant grows.
○ Germination triggers are adaptations that minimize a seeding chance of dying.
Photosynthesis:
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Pigments are used to capture light. Commonly chlorophyll (absorbs every color except
green, [reflects green])
Fixed carbon + ATP + NADPH = Glucose
Chloroplast:
○ A plastid that contains chlorophyll and in which photosynthesis takes place.
■ Chlorophyll is a pigment that helps to absorb sunlight.
Cam Photosynthesis: (Cactus in desert)
○ Capture carbon dioxide at night.
○ Let them avoid opening their Stomata during the hot day
■ Stomata is a tiny opening present on the epidermis of leaves
○ Allows a plant to photosynthesize during the day, but only exchange gasses at
night.
Adenosine Triphosphate:
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ATP As Energy:
○ Cells use ATP as a currency.
○ Phosphates are negatively charged and repel each other.
○ Unstable bonds, easily broken with water.
○ When ATP is broken, a phosphate is broken off from the molecule (becomes
ADP) and it releases energy.
■ ADP can be phosphorylated again to create more ATP. (cell recycle) It
takes energy to recycle ATP ( Energy input & Energy output)
■ Muscle cells (need a lot of ATP) can recycle 10 million ATP per second.
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Cellular Respiration
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Benefits:
○ Produce a huge amount of energy for your body to burn through.
○ Releases energy efficiently.
○ Easy to recycle.
○ Very little.
Glucose Equation
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○ Formula for Glucose: C*6 H*12 O*6 + 6O* 2 --> 6 CO* 2 + 6H*2O + ATP
○ Glucose/Food | Oxygen | Carbon Dioxide | Water
○ About 38 molecules of ATP per glucose. (range)
ATP Efficiency
○ 40% of your food energy is being stored and being used to process other
cells.
3 Stages To Cell Respiration
○ Stage 1:
■ Occurs in the cytoplasm (not in mitochondria).
■ Breaks down glucose in half (pyruvate).
■ Creates a little ATP (2).
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Stage 2:The citric acid cycle(CAC, or Krebs cycle)
■ Occurs inside mitochondria.
■ Breaks down pyruvate into carbon dioxide .
■ Little ATP formed (2).
■ Forms NADH(energy molecule).
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Stage 3:The electron transport chain
■ Occurs in inner mitochondria.
■ Team of special PROTEINS that extract energy from electrons to help
make ATP.
■ LOTS of ATP(~34).
■ Oxygen used in this stage.
Nervous Tissue: Neurons
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Neurons = nerve cells
○ Cells specialized to transmit messages
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Major Regions of neurons
■ Cell Body- Nucleus and metabolic center of the cell.
■ Processes - Fibers that extend from the cell body (dendrites & axons).
■ Axon is how neuron messages travel. They travel to Axonal terminals.
Axons end in axonal terminals.
○ Axonal terminals are separated from the next neuron by a synaptic cleft.
○ Synaptic cleft- Gap between adjacent neurons.
○ Synapse - Junction between nerves (where two axonal terminals meet).
Neurotransmitter:
○ Chemicals that travel down the synapse (space between neurons) to the next
neuron.
Starting a nerve impulse:
○ The axon part of a neuron (neurons used positive and negative).
Cell Transport: Diffusion
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Concentration Gradient: High concentration to an area of lower concentration.
Diffusion:
○ Molecules really want to reach the equilibrium (be spread equally)
○ Molecules move from a high concentration to a low concentration.
Selective permeability: Allows some but not all things to pass across the membrane.
○ Permeable = a physical quality
○ Permeability = ability of things to pass through
○ Cell membrane is selectively permeable
Entering and exiting the cell: (In General)
○ Small nonpolar molecules easily pass through the membrane.
○ Small polar molecules are transported through a protein.
○ Large molecules are moved through vesicles.
Types of Diffusion
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Passive Transport: (No Energy)
○ Uses High to Low Concentration to reach Equilibrium.
○ Simple Diffusion:
■ Through the phospholipid bilayer.
■ Happens to the small and non polar particles
○ Facilitated Diffusion: (Facilitate = To Make Easy)
■ Through Transport Proteins.
■ Happens to large or polar particles.
○ Osmosis: (Diffusion of Water Through Membrane)
■ Isotonic:
● Is the same concentration of solutes as the cell. Equal amounts of
water enter and exit the cell
■ Hypotonic:
● More solutes than a cell, more water exits a cell in hypertonic
collusion, causing the cell to shrivel or even die
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Hypertonic
● Fewer solutes than a cell. Overall more water enters a cell in
hypertonic solution. Causing the cell to expand it even burst.
Active Transport: (Uses Energy/Protein)
○ Movies from a low concentration to a high concentration. (Low to high/Opposite
of Equilibrium)
○ Uses transport proteins powered by chemical energy.
○ Cells may also use energy to move large substances across a membrane
through a vesicle.
Bulk Transport:
○ Endocytosis:
■ Process wherein the materials move into the cell rather than are engulfed
by the cell
○ Exocytosis: (Opposite of Endocytosis)
■ Process by which the contents of a cell vacuole are released to the
exterior through fusion of the vacuole membrane with the cell membrane.
■ Happens all the time in your body. You wouldn't be able to think or move
a muscle without it. When you want to move your big toe your brain sends
a message that travels through a series of nerve cells to reach your toe.
RNA
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Similarities
Has Uracil
Has Nucleobases
Ribonucleic Acid
1 Helix
Converts DNA into
instructions for
proteins.
Moves to cytoplasm.
3 Types: Messenger,
Transfer,
Ribosomal(produces
proteins)
One strand aligned
like a helix.
Resilient to UV
Shorter than DNA
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Share Cytosine,
Guanine, and Adenine
Have Helix(s)
Sugar Phosphates
Acid
Made in the nucleus
DNA
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Has Thymine
2 Helixes
Deoxyribose Acid
DNA replicates and
stores genetic
information.
Stays in nucleus
2 strands to make a
helix.
Not resilient to UV
A 5-carbon sugar
molecule and a
nitrogenous base.