Biology Notes PDF

# Unit 9 Genetic information and genetic engineering ## 1. Nucleic acids - Are large biomolecules involved in the storage and expression of genetic information in all living things - The units that form the chains of nucleic acids are nucleotides, which are made up of three elements: - **Phosph...

# Unit 9 Genetic information and genetic engineering ## 1. Nucleic acids - Are large biomolecules involved in the storage and expression of genetic information in all living things - The units that form the chains of nucleic acids are nucleotides, which are made up of three elements: - **Phosphate group:** Composed by phosphorus and oxygen - **Pentose:** Simple carbohydrate with five carbon atoms. It can be ribose (C5 H10 O5) or deoxyribose (C5 H10 O4) - **Nitrogenous base:** Cyclic compound with two or more nitrogen atoms in its composition. There are two types, formed by a double ring or formed by a single ring: - **Double ring** - Adenine (A) - Guanine (G) - **Single ring** - Thymine (T) - Uracil (U) - Cytosine (C) ## 2. DNA: Deoxyribonucleic acid - Made up of deoxyribose, adenine, guanine, thymine, and cytosine as nitrogenous bases. ## 3. RNA: Ribonucleic acid - Made up of ribose, adenine, guanine, uracil, and cytosine. ## 4. Description of DNA - The molecule forms a double helix that turns on an imaginary axis. - The two strands are complementary, so Adenine always goes with Thymine and Guanine with Cytosine. - The strands are antiparallel, that is, they are arranged in other but in opposite directions. ## 5. RNA - Is a single strand of nucleotides. - There are three types of RNA: - **mRNA (messenger RNA): ** A copy of the genetic information in the DNA. Its function is to transport this information from the nucleus to the cytoplasm, where it serves as a template for protein synthesis. - **rRNA (ribosomal RNA):** Combines with ribosomal proteins along with ribosomal proteins. - **tRNA (transfer RNA):** Transports amino acids to the mRNA, and ribosomes in the process of protein formation. ## 6. RNAi - Fragments are messenger RNA. - They are made in the nucleus and placed into the cytoplasm. - The one copied sequence, RNA polymerase or mRNA, adds one by one to the new mRNA. - The mRNA separates from the two DNA strands join together. ## 7. Protein synthesis - The process by which a protein joins the message transcribed in the mRNA, and the genetic message is joined and pasted to ribosomes in the cytoplasm. - The genetic message or message is in groups of three called **codons**. - All the processes of DNA, mRNA, and tRNA are essential and are often beneficial. ## 8. Mutations - Mutations are classified according to different criteria: - **According to origin:** - Spontaneous - Induced - **According to which cells are affected:** - Somatic - Germinal - **According to the DNA affected:** - Genetic or point mutations - Chromosomal or structural ## 9. Genetic disorders - These are mainly caused by genetics. Mostly because the allele of a gene that codes for a particular protein. # La química de la vida ## 1. Chemistry in life - All living things have something that differentiates them from non-living things. ## 2. Non-living things - These things are composed of inorganic chemical components. - Water (H2O) - Gases in the atmosphere - Compounds formed by the most abundant elements on Earth's crust. - Compounds without carbon chains. ## 3. Living things - Are formed by inorganic and organic components, exclusive to living beings. - Carbohydrates give energy. - Lipids store energy. - Proteins regulate chemical reactions and form structures. - Nucleic acid contains and transmits genetic information. ## 4. Organisation in living things - **(Unicellular):** - Subatomic particles and atoms - Molecules and macromolecules - Organelles - Cells - Tissues - Organs - System - Organism ## 5. Cell theory - A unit of life - A physiological unit - A unit of origin. - It’s a genetic unit. ## 6. Cell structure and types of cells - All Cells have: - Cell membrane - Cytoplasm - Genetic material - There are two types of cells: - **Prokaryotic cells:** Have free genetic material in the cytoplasm. They only have ribosomes (as cell organelles). Their membrane is surrounded by a cell wall. - **Eukaryotic cells:** Genetic material is separated from the cytoplasm by a double nuclear membrane called the nucleus. Centrosomes are areas near the nucleus where cytoskeleton filaments are produced. ## 7. Organelles - **Ribosomes:** Carry out protein synthesis. - **Mitochondria:** Cellular respiration takes place in mitochondria, that is, cellular respiration is responsible for supplying the energy needed for cellular activity. - **Lysosomes:** Responsible for cellular digestion (breaking down material from inside and outside the cell). - **Endoplasmic reticulum (ER):** - **RER:** Ribosomes attached to its cytoplasmic side. Same function as ribosomes. - **SER:** No ribosomes and its function is to synthesize membrane lipids. - **Golgi apparatus:** Modifies, packs, and distributes substances produced by the ER and the production of lysosomes, ## 8. Animal cell - **Centrioles:** - **Ribosomes:** - **Vacuoles:** - **Chloroplasts:** - **Mitochondria:** - **Lysosomes:** - **Cilia and flagella:** - **Nucleus:** - **Cytoplasm:** - **Rough ER:** - **Smooth ER:** - **Cytoskeleton:** - **Golgi apparatus:** ## 9. Plant cell - **Cell wall:** - **Cell membrane:** - **Nucleus:** - **ER:** - **Cytoplasm:** - **Golgi apparatus:** - **Lysosomes:** - **Ribosome:** - **Mitochondrion:** - **Cytoskeleton:**