Biologie: Glucides, Lipides, Protéines

Glucides

• Monosaccharides (monomères): Simple sugars; examples include glucose, fructose, galactose (hexoses) and ribose, deoxyribose (pentoses).
• Disaccharides: Two monosaccharides bonded together; examples include maltose, lactose, sucrose.
• Polysaccharides: Many monosaccharides bonded together; examples include starch, glycogen, cellulose.
• Functions: Energy storage, structural support.

Lipides

• Triglycerides: Composed of glycerol and fatty acids.
• Fatty Acids: Building blocks of triglycerides; can be saturated (no double bonds) or unsaturated (one or more double bonds). Unsaturated fatty acids can be cis or trans.
• Glycerol: Three-carbon alcohol component of triglycerides.
• Phospholipids: Components of cell membranes; composed of fatty acids, glycerol, and a phosphate group.
• Steroids: Lipids with a distinct four-ring structure; examples include cholesterol.

Protéines

• Amino Acids: Building blocks of proteins; linked by peptide bonds.
• Peptide Bonds: Covalent bonds forming a polypeptide chain.
• Protein Structure: Proteins fold into primary, secondary, tertiary, and quaternary structures.
• Fibrous Proteins: Structural proteins; examples include collagen, elastin, actin.
• Globular Proteins: Functional proteins; examples include enzymes, hemoglobin, albumin (pH regulation), antibodies.

Acides Nucléiques

• Composition: Nucleotides (bases, sugar, phosphate).
• Bases: Adenine, guanine, cytosine, thymine (DNA), uracil (RNA).
• Sugars: Deoxyribose (DNA), ribose (RNA).
• Phosphate: Provides the backbone of the nucleic acid.
• DNA and RNA: Deoxyribonucleic acid and ribonucleic acid; carry genetic information.
• Functions: DNA stores genetic information, RNA uses the information for protein synthesis.
• Location: DNA mainly in nucleus, RNA in nucleus and cytoplasm

ATP

• Structure: Adenosine triphosphate; composed of adenine, ribose, and three phosphate groups.
• Role: Primary energy currency of the cell.
• Importance of Phosphate Bonds: High-energy bonds are broken to release energy for cellular processes.
• Cellular Respiration: Process breaking down glucose to produce ATP (glycolysis, Krebs cycle, electron transport chain).

Enzymes

• Role: Biological catalysts, speeding up chemical reactions.
• Enzyme Types: Numerous types, each specific to a reaction.
• Catalysis: Enzymes bind to substrates, lowering activation energy and enabling reactions.
• Inhibitors: Substances that reduce enzyme activity.
• Allosteric Regulation: Enzyme activity is modified by binding of molecules at a site other than the active site.

Système Nerveux

• Nervous System Divisions: Central Nervous System (CNS) and Peripheral Nervous System (PNS).
• Neuroglia (Glial Cells): Support cells in the nervous system; include astrocytes, oligodendrocytes, microglia, ependymal cells, and ganglion gliocytes

Neurone

• Neuron Structure: Cell body, axon, dendrites, axon terminal.
• Membrane Potential: Difference in electrical charge across the cell membrane.
• Resting Potential: Stable electrical charge when the neuron is not transmitting signals.
• Graded Potential: Small, localized changes in membrane potential.
• Action Potential: Rapid, large change in membrane potential that travels along the axon.
• Propagation: Nerve impulses transmitted along an axon.
• Ions Involved: Sodium (Na+), potassium (K+), chloride (Cl−).
• Channels: Passive, voltage-gated, ligand-gated channels.
• Sodium-Potassium Pump: Maintains ion gradients.
• Myelin Sheath: Lipid-rich insulation around axons; increases conduction speed.

Synapse

• Synapse: Junction between two neurons or neuron and other cell.
• Chemical Synapse: Neurotransmitters released to transmit signals across synapse.
• Steps: Neurotransmitter release, receptor binding, response.
• Electrical Synapse: Direct conduction of electrical signals between neurons.

Encéphale (Brain)

• Lobes: Frontal, parietal, occipital, temporal, insula.
• Gyri: Postcentral gyrus, precentral gyrus.
• Motor Areas: Primary motor cortex, premotor cortex, Broca's area, oculomotor area.
• Sensory Areas: Primary somatosensory cortex, somatosensory association cortex, primary visual cortex, visual association cortex, primary auditory cortex, auditory association cortex.
• Association Areas: Anterior association area, posterior association area, limbic association area.
• Diencephalon: Thalamus, hypothalamus, epithalamus (pineal gland).
• Ventricles: Cavities in the brain filled with cerebrospinal fluid.
• White Matter: Axons connecting different brain regions.
• Cerebellum: Structure involved in coordination of movement.

Ce quiz teste vos connaissances sur les glucides, lipides et protéines. Identifiez les types de monosaccharides, disaccharides, et polysaccharides, ainsi que les structures et fonctions des lipides et protéines. Mesurez votre compréhension des concepts fondamentaux en biologie moléculaire.