Biology Concept Map #2

Energy Sytems and Energy Sources

steven stadeyにより

Macro Nutrients

Viktorija Todorovicにより

Perfil de lípidos e indicadores para el diagnóstico y control del paciente con diabetes.

Regina Díaz HMにより

Proteins are a macromolecule that consists of monomers called amino acids, and polymers that are a called polypeptides. These proteins are made up of carbons, hydrogens, oxygens, nitrogen's, and sulphur's. Proteins functions can be divided in to two areas, regulatory proteins and structural proteins. Regulatory proteins are enzymes, messenger hormones, and defence antibodies that help regulate cells. Structural proteins help with movement and build structure, as hair, cell membranes, and muscle fibers all consists of these structural proteins.

Brian Parkにより

Pathways that release energy by breaking down complex molecules into simpler compounds

Catabolic

pathways that consume energy to build larger, more complicated molecules from simpler ones

Anabolic

Chemical reactions in the body that change food into energy.

Metabolism

Metabolic Pathways

Energy is stored in the bonds between phosphate gorups of the ATP molecule.

When ATP is broken down to ADP, energy is released.

When ADP and phosphate are joined to form ATP, energy is stored again.

ATP(adenosine triphosphate) is an organic compound that provides energy to support many processes in cells.

Receptor Mediated Endocytosis Specialized pinocytosis that allows the cell to acquire bulk amounts of specific substances

Endocytosis

Pinocytosis The cell takes in extracellular fluid from the outside through vesicles

Phagocytosis The cell engulfs large food particles/other cells by extending part of the membrane

Exocytosis

Sucrose being transported against the concentration gradients uses energy created from the movement of H+ ions down the concentration gradient

Cotransport When the active transport of a solute drives the transport of other substances.

Na+/K+ Pumps & Proton Pumps

Electrogenic Pump Proteins or pumps that create a voltage difference across membranes. The energy harvested can be used for cellular work

Active Transport Needs energy to transport molecules from low to high concentration

Bulk Transport Large molecules like polysaccharides and proteins cross the membrane through vesicles

Ungated Always Open

Carrier Protein Undergo a change in shape that moves the solute across. Typically triggered by the binding and release of the molecule.

Channel Proteins Provide channels that allow a specific molecule to cross

Stretch-gated When the membrane is deformed

Voltage-gated Open and close in response to changes in membrane potential

Ligand-gated Open and close when a neurotransmitter binds to the channel

Aquaporin transports water across the membrane. The amino acids with polar R goups make up the interior of the protein while the exterior part of the protein is made up of amino acids with non polar R groups.

Facilitated Diffusion Passive transport but aided by proteins

*Plant cells are best in a hypotonic environment (turgid)

*Animal cells are best in an isotonic environment

Hypotonic Solute concentration is greater on the inside of the cell.

Hypertonic Solute concentration is greater on the outside of the cell.

Isotonic Solute concentration is the same inside and outside of the cell.

Tonicity Ability of a solution to cause a cell to lose or gain water

Osmosis Diffusion of water across a membrane from a lower solute concentration to a higher solute concentration until it's equal on both sides.

Diffusion The tendency for molecules to spread out, moving from areas of high concentration to low concentration.

Signal Molecule Binding

Intracellular Receptor

Step 1: Signal molecule passes through membrane

A signaling molecule that is released by a different cell goes through the membrane. The membrane, phospholipid bilayer only allows nonpolar/hydrophobic molecules to go through.

Signal molecule is nonpolar/hydrophobic

Step 2: Signal molecule binds to receptor protein

Once the signal molecule goes through the membrane, it binds to the receptor protein and activates it. When it is activated, the protein changes shape.

Step 3: Signal-Receptor complex enters the nucleus

Once the signaling molecule binds to the receptor protein, the protein enters the nucleus and starts to activate the genes that control water and sodium flow.

Step 4: Protein prompts transcription of gene into mRNA

The protein that is bound to DNA starts the transcription of a specific gene into mRNA.

Step 5: mRNA is translate into a specific protein

The mRNA is transcribed and a gene is expressed to create a protein.

Membrane Receptor

Step 1: Reception

Reception is the process in which a signal molecule is received. A signal molecule binds to a receptor protein which causes it to change shape. Polar signal molecules are the ones that bind to membrane receptors.

Step 2: Transduction

Protein Kinase 1 Activated

Kinase 1 Activates Kinase 2

Kinase 2 Phosphorylates a protein

Protein Phosphatase removes Phosphate group from Kinases

Step 3: Response

Passive Transport Diffusion of a substance across a membrane with no energy investment

Types of Transport

Polarity and size determines whether it can cross rapidly, slowly, or not even at all.

Hydrophobic molecules can easily cross the membrane while polar molecules do not

Plasma Membranes are selectively permeable

Signaling Molecule

Enzyme

G Protein

G protein couple receptor

Transmembrane Protein Fully inserted and spans the entire membrane with parts inside and outside of the cell. N-terminus (amino) & C-terminus (carboxyl terminus)

Integral Proteins Partially or Fully Inserted

Peripheral Proteins Anchored to the membrane

Proteins Some anchored, some move and drift

Cholesterol Presence between phospholipids around 37°C, movement is reduced. At low temperatures, packing is prevented.

Temperature Above a temperature, the lipid is fluid. Below, the lipid is in a gel phase and rigid.

Saturated Fatty Acid Tail Lipids are tightly packed and cannot move

Unsaturated Fatty Acid Tail Lipids are not tightly packed and can move in the membrane

Phospholipid Bilayer Each phospholipid has a hydrophobic fatty acid tail and a hydrophilic head (due to the presence of a phosphate group). They are amphipathic molecules.

Cell Membranes

cellular respiration

Step 1: Glycolysis

breaks down glucose into 2 molecules of pyruvate

hexokinase transfers phosphate group from ATP to glucose to form glucose-6 phosphate

phosphofructokinase transfers a phosphate group from ATP to the opposite end of the sugar, forming fructose 1,6-biphosphate

input: glucose, 2 ATP output: 4 ATP, 2 NADH, 2 pyruvate

occurs in the cytoplasm, outside of the mitochondria

Step 2: Pyruvate Oxidation and Citric Acid Cycle

citric acid cycle

acetyl CoA adds its 2-carbon group to oxaloacetate to form citrate; highly exergonic reaction

isocitrate is oxidized and NAD+ is reduced (redox reaction) to form a-ketoglutarate

input: 2 acetyl CoA output: 2 ATP, 6 NADH, 2 FADH

pyruvate is oxidized; forms acetyl CoA

input: 2 pyruvate output: 2 acetyl CoA, 2 NADH

Step 3: Oxidative Phosphorylation

electron transport chain

energy is released as electrons move down the chain

energy pumps H+ against the concentration gradient into the intermembrane space

output: 26-28 molecules of ATP

chemiosmosis

H+ goes back down the concentration gradient through a membrane transfer protein

energy associated with the gradient is used to add Pi to ADP to form ATP

Cell Communication/signaling

Releasing a signal

Cells that are not close enough to touch each other, can communicate with signaling molecules (ligands). The signaling molecule then binds to a receptor protein.

Synaptic Signaling

1) An action potential arrives, and depolarizes the presynaptic membrane

2) Voltage-Gated channels open and Ca ions enter the cell

3) The high Ca concentration cause neurotransmitters to be released into the synaptic cleft

4) The neurotransmitter binds to ion channels. This may allow Na and K ions to diffuse through

Hormonal Signaling

Paracrine Signaling

Physical contact

Eukaryotic cells can communicate through physical contact. Animal and Plant cells have junctions that connect them to neighboring cells. Animal cells have gap junctions while Plant cells have plasmodesmata. Molecules are able to move through these junctions from one cell to the other.

Junctions

Energy Transfer

Thermodynamics

Laws of Thermodynamics

Every energy transfer or transformation increases the entropy of the universe

A consequence of a loss of heat creates disorder in the universe. It is possible for order to increase locally, but the universe as a whole tends to disorder.

Entropy - a measure of disorder in the universe

Energy can be transferred and transformed, but it cannot be created or destroyed

This law is also known as the principle of conservation of energy. The energy of the universe is constant. Organisms can’t recycle their energy because, during energy transformation, some energy is converted to thermal energy and is lost to the surroundings as heat and not available to do work.