Lecture Two - Biology PDF

Lecture Two Vocabulary - DNA (deoxyribonucleic acid): The genetic material of all cells and many viruses. The molecule that encodes genetic information. - Pollen: The cells that carry the male DNA of a seed plant. - Biotechnology: A set of biological techniques developed through basic...

Lecture Two Vocabulary - DNA (deoxyribonucleic acid): The genetic material of all cells and many viruses. The molecule that encodes genetic information. - Pollen: The cells that carry the male DNA of a seed plant. - Biotechnology: A set of biological techniques developed through basic research and now applied to research and product development. - Cultivar: Synonymous with variety; the international equivalent of variety. - Hybrid: Seed or plants produced as the result of controlled cross-pollination as opposed to seed produced as the result of natural pollination. Reading  What is Biology? Biology is the scientific study of life and living organisms, encompassing a wide range of fields that explore the structure, function, growth, origin, evolution, and distribution of living things. One fundamental aspect of biology is the understanding of reproduction and genetics, which are critical for the continuation of species. In seed plants, reproduction involves intricate processes where male and female cells unite to create new life. Pollen consists of cells that carry the male DNA, and when it is transferred to the ovule—an outgrowth of the ovary of a seed plant—fertilization occurs. The ovule encloses the embryo, which will eventually develop into a seed. This intricate dance between pollen and ovule is essential for the propagation of plant species.  At the molecular level, DNA serves as the genetic material found in all cells and many viruses, carrying the instructions necessary for life. Genes, the most basic units of heredity, dictate everything from physical traits to biological functions. Together, these genes make up the genome, the complete genetic blueprint of a living organism. Enzymes, vital proteins that speed up the chemical reactions taking place within cells, play a key role in facilitating the biological processes necessary for life. In modern biology, techniques such as the gene gun, invented at Cornell University, allow scientists to introduce genetic material into new organisms. This innovation has transformed fields like agriculture and medicine, enabling the development of genetically modified organisms (GMOs) and advancing our understanding of genetics. - Answer the following questions: 1. _________________________ is a device that allows for the introduction of genetic material into new organisms. A) Microscope B) Gene gun C) Centrifuge D) PCR machine 2. Pollen consists of _________________. A) Female DNA B) Cells that carry male DNA C) Enzymes D) Nutrients 3. Changes to ____________________ can occur naturally or artificially through substances known as mutagens. A) Genetic material B) Gene gun C) The embryo D) PCR machine 4. The ________________ is an outgrowth of the ovary of a seed plant that encloses an embryo. A) Seed B) Ovule C) Pollen D) Stem 5. The most basic unit of heredity is _________________. A) Genome B) Chromosome C) Gene D) RNA 6. DNA serves as the ________________ found in all cells and many viruses. A) Enzyme B) Genetic material C) Protein D) Hormone 7. Enzymes are ________________ that speed up chemical reactions within cells. A) Carbohydrates B) Nucleic acids C) Vital proteins D) Minerals 19. 8. The complete genetic blueprint of a living organism is known as its ________________. A) Gene B) Genome C) Chromosome D) DNA --------------------------------------------------- Grammar  Present perfect We form the present perfect tense with the verb have and the past participle of the verb. The past participle is the same as the past simple (-ed) for regular verbs. For irregular verbs, it’s the form in the 3rd column.  Common Tense Markers Already / Yet / Ever / Never / Just / Since / For / Before Ex. - I have already prepared breakfast. - Has the post come yet? - I have never lied in my life. - Have you ever been to England? - We haven’t received any mail since we were retired -We haven’t met before - I have lived in Texas for 10 years. - Tom has just come to the office USE OF PRESENT PERFECT TENSE: 1- Present Perfect Tense is used to express an action that happened at an unspecified time in the past and the impact of the event is now continuing. - She has lost her wallet. ( She can’t find it ) - My sister has broken her arm. (Her arm is still broken.) 2- Present Perfect Tense is used to express an action that ended recently. We often use words like “just” or “recently” for the events taking place a very short time before now. - My mother has just cleaned the house. - We have recently eaten dinner.  3- Present Perfect Tense is used to talk about unfinished actions or states or habits that started in the past and continue to the present. In such sentences, it is emphasized that how long the action has continued. Examples: - The student has studied maths for three months. - I have lived in Paris for five years. - My son has been sick since Monday. - He has worked in Berlin since he graduated from the university. - She haven’t been calm since the accident. 4- Present Perfect Tense is used to express repeated actions in an unspecified time between past and now. Examples: - We have watched that movie three times. - I have seen David several times. - She have had six exams so far this semester.