s1 exam flashcards

Priority Standard - P.AP CELLS 1.1a, 1.2a: Chemistry of Life

Major Macromolecules and Their Roles in Cellular Function

Carbohydrates

Structure: 

Composed of carbon (C), hydrogen (H), and oxygen (O)Types:

Monosaccharides: Simple sugars (e.g., glucose, fructose).

Polysaccharides: Complex carbohydrates (e.g., starch, glycogen, cellulose).

Function: 

Primary energy source for cells.

Structural components in plants (cellulose) and energy storage (starch in plants, glycogen in animals).

Lipids

Structure: 

Composed mainly of fatty acids and glycerol; hydrophobic molecules.

Types:

Triglycerides: Energy storage.

Phospholipids: Major component of cell membranes, with hydrophilic heads and hydrophobic tails.

Steroids: Hormones and signaling molecules (e.g., cholesterol).

Function:

Form cellular membranes.

Store energy and provide insulation.

Proteins

Structure: 

Made of amino acids linked by peptide bonds; can have complex three-dimensional shapes.

Functions:

Enzymes catalyze biochemical reactions.

Structural roles (e.g., collagen in connective tissue).

Transport molecules (e.g., hemoglobin in red blood cells).

Nucleic Acids

Structure: 

Composed of nucleotides, which include a sugar, phosphate group, and nitrogenous base (adenine, thymine, cytosine, guanine, uracil).

Types:

DNA: Stores genetic information.

RNA: Involved in protein synthesis.

Function:

Encode genetic instructions for development and functioning of living organisms.

Key Terms

Monomers: Basic building blocks of macromolecules.

Polymers: Large molecules formed by linking monomers.

Dehydration Synthesis: Process of joining two molecules by removing water.

Hydrolysis: Process of breaking down a polymer by adding water.

Priority Standard - P.AP CELLS 2.2a, 2.3a: Cell Structure and Function

Comparing and Contrasting Specialized Cells

Cell Theory: 

All living organisms are made of cells.

Cells are the basic unit of structure and function in living things.

All cells arise from pre-existing cells.

Types of Cells:

Unicellular: Organisms consisting of a single cell (e.g., bacteria).

Multicellular: Organisms composed of multiple specialized cells (e.g., humans, plants).

Specialized Cells:

Examples: Muscle Cells: Contain many mitochondria for energy production.

Nerve Cells: Have long axons for transmitting signals.

Epithelial Cells: Form protective layers and may have specialized structures like cilia.

Prokaryotic vs. Eukaryotic Cells:

Prokaryotic Cells: No nucleus or membrane-bound organelles (e.g., bacteria).

Eukaryotic Cells: Have a nucleus and organelles (e.g., plant and animal cells).

Key structures/organelles and Their Functions

Ribosomes: Sites of protein synthesis.

Plasma Membrane: Controls the movement of substances in and out of the cell.

Cytoplasm: Jelly-like substance where cellular processes occur.

Nucleus: Contains genetic material (DNA).

Rough ER: Studded with ribosomes; synthesizes proteins.

Smooth ER: Synthesizes lipids and detoxifies substances.

Golgi Apparatus: Modifies, sorts, and packages proteins.

Lysosomes: Contain enzymes for digestion.

Mitochondria: Produce ATP through cellular respiration.

Chloroplasts: Sites of photosynthesis in plant cells.

Priority Standard - P.AP CELLS 3.1a: Cell Transport and Homeostasis

Cell Membranes and Dynamic Homeostasis

Plasma Membrane:

A selectively permeable barrier that regulates the entry and exit of substances.

Membrane Proteins:

Integral and peripheral proteins that assist in transport, communication, and signaling.

Transport Mechanisms:

Passive Transport: Movement of substances without energy (e.g., diffusion, osmosis).

Active Transport: Movement of substances against their concentration gradient, requiring energy (ATP).

Diffusion: Movement of molecules from an area of high concentration to low concentration.

Osmosis: Diffusion of water across a semipermeable membrane.

Concentration Gradients: 

The difference in concentration of a substance across a space, driving diffusion.

Endocytosis and Exocytosis:

Endocytosis: Process of taking in large particles or fluids (e.g., phagocytosis for solids, pinocytosis for liquids).

Exocytosis: Process of expelling materials from the cell.

Feedback Loops:

Positive Feedback: Amplifies responses (e.g., blood clotting).

Negative Feedback: Damps responses to maintain homeostasis (e.g., temperature regulation).

Maintaining Homeostasis

Cells maintain homeostasis by regulating the movement of materials in and out of the cell through various transport mechanisms, ensuring optimal internal conditions for cellular processes.

Study Guide: Honors Biology Unit 2 - Cell Processes Vocabulary

P.AP Cells 5.1, 5.2 Cells Growth and Division

Cell Cycle

The cell cycle is a series of stages that a cell goes through as it grows and divides. Understanding each phase is crucial for grasping how cells replicate and function.

Interphase

Interphase is the longest phase of the cell cycle, during which the cell prepares for division. It has three sub-phases:

G1 Phase (Gap 1)

Description: The cell grows and synthesizes proteins and organelles. It also performs its normal functions.

Key Events:

Cell increases in size.

RNA and proteins are synthesized.

Organelles are duplicated.

S Phase (Synthesis)

Description: The cell replicates its DNA, resulting in two identical sets of chromosomes.

Key Events:

DNA replication occurs.

Each chromosome is duplicated, forming sister chromatids.

G2 Phase (Gap 2)

Description: The cell continues to grow and prepares for mitosis.

Key Events:

Final preparations for cell division.

Synthesis of proteins necessary for mitosis.

Checks for DNA damage and ensures all DNA is replicated correctly.

Mitosis (M Phase)

Mitosis is the process of cell division that results in two identical daughter cells. It consists of several phases:

Prophase

Chromatin condenses into visible chromosomes.

The nuclear envelope begins to break down.

The mitotic spindle begins to form.

Metaphase

Chromosomes align at the cell's equatorial plane (metaphase plate).

Spindle fibers attach to the centromeres of the chromosomes.

Anaphase

Sister chromatids are pulled apart toward opposite poles of the cell.

The cell begins to elongate.

Telophase

Chromatids reach the poles and begin to decondense back into chromatin.

The nuclear envelope re-forms around each set of chromosomes.

Cytokinesis

The cytoplasm divides, resulting in two separate daughter cells.

In animal cells, this process involves the formation of a cleavage furrow; in plant cells, a cell plate forms.

Key Terminology: 

Chromosomes: Structures made of DNA and protein that contain genetic information.

Chromatin: The relaxed form of DNA in the nucleus during interphase.

Sister Chromatids: Identical copies of a chromosome that are connected by a centromere.

Cellular Energy

Understanding how cells harness and use energy is fundamental to biology.

Enzymes

Definition: Biological catalysts that speed up chemical reactions without being consumed in the process.

Substrate: The reactant that an enzyme acts upon.

Product: The result of a chemical reaction catalyzed by an enzyme.

Catalytic/Catalyze: The process by which enzymes accelerate biochemical reactions.

Anabolic: Pathways that build larger molecules from smaller ones, requiring energy (e.g., protein synthesis).

Catabolic: Pathways that break down larger molecules into smaller ones, releasing energy (e.g., cellular respiration).

Activation Energy: The minimum energy required to start a chemical reaction. Be able to read the Reaction Energy Grass

ATP (Adenosine TriPhosphate)

Description: The primary energy carrier in cells.

ADP (Adenosine Diphosphate): A lower-energy molecule that can be converted back to ATP by adding a phosphate group.

Exothermic: Reactions that release energy (graph shows a downward slope).

Endothermic: Reactions that absorb energy (graph shows an upward slope).

P.AP Cells 6.1,7.1 Photosynthesis and Respiration

Photosynthesis

Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy.

Overall Equation

6H2O+6CO2+(Light Energy)→C6 H12 O 6 +6O2

​

  Key Structures

Chloroplast: The organelle where photosynthesis occurs.

Thylakoid: Membrane-bound structures within chloroplasts where the light-dependent reactions take place.

Grana/Granum: Stacks of thylakoids.

Stroma: The fluid-filled space surrounding the thylakoids, site of the light-independent reactions (Calvin Cycle).

Chlorophyll: The green pigment that absorbs light energy.

Photosynthesis Phases

Light Dependent Reactions

Occur in the thylakoid membranes.

Inputs: Water and light energy.

Outputs: Oxygen (O2), ATP, and NADPH.

Light Independent Reactions (Calvin Cycle)

Occur in the stroma.

Inputs: Carbon dioxide (CO2), ATP, and NADPH.

Outputs: G3P (glyceraldehyde-3-phosphate), which can be converted into glucose.

Cellular Respiration

Cellular respiration is the process by which cells convert glucose into usable energy (ATP).

Overall Equation C6H12O6+O2→6H2O+6CO2+(ATP)

Types of Respiration

Aerobic Respiration: Requires oxygen; produces a high yield of ATP.

Anaerobic Respiration/Fermentation: Occurs without oxygen; produces less ATP and can result in byproducts like alcohol or lactic acid.

Key Structures

Mitochondria: The organelle where cellular respiration occurs.

Cytoplasm: The fluid inside the cell where glycolysis occurs.

Matrix: The innermost compartment of the mitochondria, site of the citric acid cycle.

Inner Membrane/Cristae: The folded inner membrane of the mitochondria, site of the electron transport chain (ETC).

Cellular Respiration Phases

Glycolysis

Occurs in the cytoplasm.

Breaks down glucose into pyruvate, yielding a small amount of ATP and NADH.

Citric Acid Cycle (Krebs Cycle)

Occurs in the mitochondrial matrix.

Processes pyruvate to produce NADH, FADH2, and ATP.

Electron Transport Chain (ETC)

Occurs across the inner mitochondrial membrane.

Uses electrons from NADH and FADH2 to create a proton gradient, driving ATP synthesis.

Fermentation Types

Alcoholic Fermentation: Converts pyruvate into ethanol and carbon dioxide (e.g., in yeast).

Lactic Acid Fermentation: Converts pyruvate into lactic acid (e.g., in muscle cells during anaerobic conditions).

Major Macromolecules and Their Roles in Cellular Function

Carbohydrates

Structure:

• Composed of carbon (C), hydrogen (H), and oxygen (O), typically in a ratio of 1:2:1.

• Types:

  • Monosaccharides: Simple sugars like glucose, fructose, and galactose. They serve as the building blocks for more complex carbohydrates.

  • Disaccharides: Formed from two monosaccharides (e.g., sucrose, lactose) through dehydration synthesis.

  • Polysaccharides: Large, complex carbohydrates (e.g., starch, glycogen, cellulose). They serve as energy storage or structural components.

Function:

• Primary energy source: Carbohydrates provide quick energy to cells, especially glucose, which is crucial for cellular respiration.

• Structural roles: Cellulose provides rigidity to plant cells, while chitin is important in the exoskeleton of arthropods.

• Energy storage: Glycogen serves as an energy reserve in animals, while starch does so in plants.

Lipids

Structure:

• Composed primarily of fatty acids and glycerol, lipids are characterized by their hydrophobic nature, which makes them insoluble in water.

• Types:

  • Triglycerides: Composed of three fatty acids bonded to a glycerol backbone, they are used mainly for energy storage.

  • Phospholipids: Major components of cell membranes with a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails.

  • Steroids: Lipids with a structure characterized by four fused carbon rings; examples include cholesterol and hormones (e.g., testosterone, estrogen).

Function:

• Cellular membranes: Lipids form the bilayer structure of cell membranes, which is crucial for maintaining cell integrity and function.

• Energy storage: Triglycerides store energy for long-term use, releasing fatty acids during cellular respiration.

• Insulation and protection: Lipids help insulate organs and tissues, providing a protective layer.

Proteins

Structure:

• Composed of amino acids linked together by peptide bonds, proteins can fold into complex three-dimensional shapes, determined by their amino acid sequences.

Functions:

• Catalysis: Enzymes accelerate biochemical reactions by lowering the activation energy needed, thus facilitating metabolic processes.

• Structural roles: Proteins like collagen provide strength and support to various tissues, while keratin is a structural protein found in hair, skin, and nails.

• Transport: Hemoglobin in red blood cells transports oxygen throughout the body, while membrane proteins facilitate the transport of substances across cellular membranes.

Nucleic Acids

Structure:

• Composed of nucleotides, which include a sugar (ribose or deoxyribose), a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, guanine, uracil for RNA).

• Types:

  • DNA: Stores and transmits genetic information; composed of two strands forming a double helix.

  • RNA: Involved in protein synthesis and gene expression; exists in various forms (mRNA, tRNA, rRNA) that play roles in different stages of protein production.

Function:

• Genetic encoding: DNA encodes the genetic instructions essential for development, functioning, growth, and reproduction of all living organisms.

• Protein synthesis: RNA plays a pivotal role in translating genetic information into proteins, facilitating the expression of genes and the functioning of cells.

Key Terms

• Monomers: Basic building blocks of macromolecules, such as amino acids for proteins and nucleotides for nucleic acids.

• Polymers: Large molecules formed by linking monomers through various chemical processes.

• Dehydration Synthesis: A reaction that joins two molecules by removing a water molecule, essential for forming larger macromolecules.

• Hydrolysis: A reaction that breaks down a polymer by adding water, crucial for digestion and metabolic processes.