2024 Biology Midterm Study Guide PDF

## Biology Midterm Exam Study Guide ### Unit 1: #### Chapters 1-3 - Introduction to Biology - Characteristics of Life - The Scientific Method - Taxonomy & Biochemistry ### Sample & Practice Questions 1. What is Biology? The study of life. 2. What kinds of things can be studied or examined in this d...

## Biology Midterm Exam Study Guide ### Unit 1: #### Chapters 1-3 - Introduction to Biology - Characteristics of Life - The Scientific Method - Taxonomy & Biochemistry ### Sample & Practice Questions 1. What is Biology? The study of life. 2. What kinds of things can be studied or examined in this discipline? Through Biology, we can study living things in this world, how they work and the processes behind nature. 3. How do we know what God wants us to do with creation? (Gen. 1:28) God told us to be stewards of nature, to take care of his creation. ### Scientific Method Practice In an experiment to test which type of soil a bean grows best in, a science class chooses sand, peat moss, and potting soil to grow kidney beans in. - **Design an experiment to test the variables they've chosen**: - The control variable will be the plant type (kidney beans), the amount of water, the amount of soil, the same type of pot, and the same amount of sunlight that each plant gets. - The dependent variable will be the soil type. - Over the course of a month, each pot will be taken care of, and whatever plant grows the tallest (or longest), that will be the soil that the kidney beans grow the best in. - **Identify the independent, dependent, and any control variables:** - **Independent**: Soil type - **Dependent**: Amount of growth - **Control**: Plant type, amount of soil, amount of water, amount of sunlight. - **Identify the problem and formulate a hypothesis:** - **Problem**: Does the type of soil affect how well a kidney bean plant grows? - **Hypothesis**: If the type of soil affects the growth of a plant, then the potting soil will be the best for the growth of the kidney beans. ### Characteristics of Life Practice 1. Are both complex and organized. 2. Acquire and use both materials and energy. 3. Exhibit some capacity to regulate their internal conditions (homeostasis). 4. Show the capacity for growth. 5. Respond to stimuli. 6. Reproduce themselves. 7. Have the capacity to evolve. ### Levels of Organization Practice - **Things to consider:** - If an animal has eyes, can it be multicellular? - Yes. - Where does digestion fall in the levels of organization? - Organ System - Where does the leaf of a plant fall in the levels of organization? - Organ System ### Taxonomy - **Carrolus Linnaeus** - **Aristotle** - **Kingdom, Phylum, Class, Order, Family, Genus, Species** - **Binomial nomenclature (Photoshopicus falis example or real-life Homo sapien, Charadrius melodus)** ### Biochemistry - **Chemical Bonds & Reactions** | Type of Bond | Defined | Example | |---|---|---| | Covalent | Bond formed by the sharing of electrons in a bond | Carbon dioxide | | Ionic | Bond formed by the "stealing" of electrons | Sodium chloride (NaCl) | | Hydrogen Bonds | Weak electrostatic interactions between hydrogen and oxygen | Water | - **Biological Macromolecules** - Be able to explain how and why the (water) molecule is at the heart of all things biology. (How do hydrogen bonds between water molecules make life possible?) ### The Cell Membrane - **Describe the functions of the chemicals found in the cell membrane:** | Chemical | Function in the Cell Membrane | |---|---| | Lipids | Phospholipids make up the phosphate head and 2 fatty acid tails in the membrane. Cholesterol also keeps the fatty acid tails from sticking to each other (like oil or butter). | | Carbohydrates | Cell to cell recognition (like name tags). | | Proteins | Serves as anchors and transport helpers. | - **Describe/Draw the cell membrane below:** - (Draw a simple representation of a phospholipid bilayer with labels for the phospholipid head, fatty acid tails, and the membrane) ### Be able to identify the functions of cell structures and organelles: Plant Cell - **Vacuole:** (Write the function of the Vacuole in the Plant Cell) - **Chloroplast:** (Write the function of the Chloroplast in the Plant Cell) - **Cell Wall:** (Write the function of the Cell Wall in the Plant Cell) - **Mitochondria:** (Write the function of the Mitochondria in the Plant Cell) - **Nuclear:** (Write the function of the Nuclear in the Plant Cell) - **Nucleus:** (Write the function of the Nucleus in the Plant Cell) ### Animal Cell - **Notes on Functions:** #### Cell Membrane 1. **Composed primarily of phospholipids:** - Phosphate head and two fatty acid tails. 2. **Proteins:** - Serve as anchors and transport helpers. 3. **Carbohydrates:** - Serve the purpose of cell-to-cell recognition (like name tags). - Serve in cell-to-cell junctions holding cells together). 4. **Other Lipids:** - Cholesterol - keeps fatty acid tails from sticking to each other and keeps the membrane fluid and supple. #### Interior features: 1. **Cytoplasm:** - The internal fluid of the cell (90% water and 10% other solutes). 2. **Cytoskeleton:** - Provides structural integrity for the cell. 3. **Mitochondria:** - Site of cellular respiration. 4. **Rough ER:** - Makes proteins and membranes. 5. **Smooth ER:** - Stores calcium ions. - Manufactures lipids. - Destroys toxic substances. 6. **Lysosomes:** - Site of cellular digestion 7. **Vacuoles:** - Storage "containers" for water, toxins, and food 8. **Nucleolus:** - Located within the nucleus ### Energy #### Chapters 4-8 ### Cellular Metabolism Cellular Metabolism is defined as... Chemical reactions that take place within the cell. - **Anabolic metabolisms:** Builds up larger molecules from smaller molecules - **Catabolic metabolisms:** Breaks down the larger molecules into smaller molecules #### Enzymes - **Word Bank:** Catalysts, Enzymes, Activation 1. The amount of energy needed for a chemical reaction to occur is known as **Activation energy**. 2. Chemicals that can lower the activation energy of a chemical reaction are known as **catalysts**. 3. Biological catalysts are known as **Enzymes**. #### Overview Remember, according to the first law of thermodynamics, **energy cannot be created or destroyed**. BIBLICAL EXCEPTION found in... (Write the exception). #### Vocabulary to remember - **Autotrophs:** Organisms that can produce their own food. (examples: Plants, algae and bacteria) - **Heterotrophs:** Organisms that cannot produce their own food and must get it by other organisms. (examples: Animals, fungi). #### ATP & The ATP cycle - (Draw a diagram representing the ATP cycle) - ATP is created and ADP is constantly being recycled into ATP again. #### Aerobic Respiration | Step | Overview | Location | ATP Produced | |---|---|---|---| | Glycolysis | Glucose is split into two 3-carbon containing molecules. | Cytoplasm | 2 Net – “A little" | | The Kreb's Cycle | Pyruvate is broken down into CO2 and the electrons are readied to be carried to the next step by NADH and FADH2 | Mitochondria | Apx. 6 – “A little bit more than glycolysis” | | The Electron Transport Chain | Using enzymes embedded in the mitochondrial membrane, hydrogen ions are pumped back and forth to create a chemical gradient that forces hydrogen ions through an enzyme called ATP-synthase that adds phosphates to ADP to create ATP again. | Mitochondria | Apx. 32 - “The most” | #### What is the chemical equation for cellular respiration? C6H12O6 + 6O → 6 CO2 + 6 H2O #### What is the chemical equation for photosynthesis? 6 CO2 + 6 H2O → C6H12O6 + 6O ### Mitosis & The Cell Cycle 1. When a cell becomes too large, what might it do? Self-destruct 2. Cells are grouped into either eukaryotes or prokaryotes based on what information? Whether or not they have membrane bound organelles. ### Mitosis - **Beginning with early prophase, be sure you can recognize the steps of the following process. The purpose of this process is genetic continuation** - (Draw diagrams representing the stages of mitosis: Early Prophase, Prophase, Metaphase, Anaphase, Telophase) #### Practice Questions: 1. Chemicals that regulate the cell cycle are called **regulators**. 2. **Self destruction** results when cells no longer respond to cell cycle regulators. 3. Sometimes, **apoptosis**, or programmed cell death will occur to protect an organism from cancer. ### Meiosis - The purpose of the following process is **genetic variability**. - The type of reproduction it is associated with is **sexual reproduction**. - (Draw diagrams representing the stages of meiosis: Prophase I, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II, Telophase II) #### Define Haploid: Half a chromosome count #### Define Diploid: A full chromosome count ### Unit 4: Molecular DNA & Protein Synthesis #### Chapters 9, 10, 11 #### Modeling DNA - **Practice Questions:** 1. What are the monomers of DNA? - **Nucleotides** 2. What molecules make up the “backbone” of the DNA molecule? - **Nucleotides** - (Draw a simple diagram representing the double helix of DNA) 3. What molecules make up the "ladder-rungs" of the DNA molecule? - **Nitrogen base pairs.** ### DNA Replication | Enzym | Function in DNA | |---|---| | DNA Helicase | Unwinds the double helix | | RNA Primase | Lays down the RNA primer, which give instructions for the base pairs. | | DNA Polymerase | Adds the nitrogen bases. | ### Protein Synthesis | Type of RNA | Function | Differences (as compared to DNA) | |---|---|---| | rRNA | Composes the ribosome | Ribose Sugar | | tRNA | Carries amino acids to ribosome based on the anti-codon | Uracil instead of Thymine | | mRNA | Carries a copy of the DNA | Single strand | - **Practice: Be able to describe the process of protein synthesis in your own words:** - **Transcription:** The strand of DNA is unwound, and mRNA is produced. - **Translation:** The different amino acids are carried by the tRNA based on the anti-codon until a new protein is formed. ### Unit 5: Mendelian Genetics #### Chapters 12-15 #### Mendelian Genetics - **Practice Problems:** 1. **What principle did Mendel coin when he did the following cross that produced only one color flower even though he crossed flowers of two different colors?** - **Principle of Dominance.** 2. **What organism did Mendel use primarily for his research in Genetics?** - **Pea plants.** 3. **In cross above only one trait (flower color) was observed. This kind of cross is also known as a monohybrid cross.** 4. **In the event that two organisms are crossed and two traits are observed (i.e. seed shape and seed color), this is called a dihybrid cross.** #### Punnet Square Practice - **Draw a punnet square that is - a cross between a parent homozygous - for the dominant purple flower color in peas with another parent that is - homozygous recessive for the recessive white flower color in peas. - Then draw a second square illustrating a self-pollination between one of the offspring plants.** - (Draw two Punnett squares, one showing a cross between a homozygous dominant parent and a homozygous recessive parent, and the other showing the self-pollination of an offspring with the dominant and recessive alleles. Provide labels for each allele and the resulting genotype) #### Vocabulary terms to remember: - **Allele**: A variation of a gene - **Homozygous**: Having two identical alleles for a trait - **Heterozygous**: Having two different alleles for a trait - **Recessive**: An allele that is only expressed when two copies of it are present - **Dominant**: An allele that is expressed even when only one copy of it is present - **Genotype**: The genetic makeup of an individual - **Phenotype**: The observable characteristics of an individual - **Sex-linked traits**: Traits that are located on the sex chromosomes - **Pedigrees**: Charts that show the inheritance patterns of a trait within a family #### Exceptions to Mendel's Rules | Exception | Description | Example | |---|---|---| | Incomplete Dominance| When neither trait is fully expressed, and a mix of the traits is shown. | White and Black make grey. | | Codominance | When both traits are shown | A spotted cow instead of a completely black or white cow. | | Multiple Alleles | Inheritance patterns where there are more than one phenotype | Blood type, rabbit fur. | | Polygenic Traits/Continuous Variation | Traits that are controlled by more than one gene | Skin color, hair color, fingerprint pattern | ### Unit 6: Genetic Technology (Chapter 16) #### Define Terms: - **Genetic Engineering:** Altering specific genes to create a desired outcome - **DNA Technology:** The use of DNA to create new products or to diagnose or treat diseases - **Recombinant DNA:** DNA that has been created by combining genetic material from two or more sources - **Reverse Transcriptase:** An enzyme that catalyzes the synthesis of DNA from an RNA template - **Restriction Enzymes:** Enzymes that cut DNA at specific sequences - **Vectors:** Carries foreign DNA into a host cell - **Polymerase Chain Reaction:** A laboratory technique used to amplify DNA