Biology Chapter: Metabolism and Photosynthesis

The spontaneous generation of organic molecules was experimentally demonstrated by Stanley Miller in 1953. He simulated early Earth conditions by mixing gases like H2, CH4, NH3, and water vapor in a closed container and passing electric sparks through it. This created amino acids, key building blocks of proteins, indicating that basic organic molecules could arise from non-living matter.

Macromolecules, complex molecules essential for life, can form spontaneously from simpler building blocks. For example, heating a mixture of amino acids can lead to the formation of polypeptides, building blocks of proteins. This process, known as polymerization, suggests that essential biomolecules could arise naturally.

The ability to self-replicate is a fundamental property of life. Nucleic acids, like RNA, are capable of directing their own replication, ensuring the perpetuation of genetic information. This replication is based on specific pairings of nucleotides: adenine (A) with uracil (U), and guanine (G) with cytosine (C).

The central dogma of molecular biology describes the flow of genetic information in living organisms. It states that DNA, the genetic blueprint, is transcribed into RNA, which is then translated into proteins. These proteins perform various functions within the cell, contributing to its survival and growth.

The genetic code is a set of rules that dictates how the sequence of nucleotides in DNA or RNA is translated into the sequence of amino acids in a protein. Each three-nucleotide codon specifies a particular amino acid, enabling the synthesis of proteins based on the genetic information.

The first cell is hypothesized to have originated from a self-replicating RNA molecule surrounded by a membrane composed of phospholipids. Phospholipids consist of hydrophobic tails embedded in the membrane and hydrophilic heads exposed to the external environment. This structure allowed for the compartmentalization of essential molecules and paved the way for the evolution of life.

The origin of life is a complex process that involves the spontaneous formation of organic molecules, their polymerization into macromolecules, the emergence of self-replicating RNA, and the encapsulation of these molecules within a phospholipid membrane. These steps led to the formation of the first cells, paving the way for the evolution of life as we know it.

The Miller-Urey experiment, which produced simple amino acids from basic inorganic molecules, provides support for the idea that life could have originated from non-living material. Later experiments and discoveries further confirmed this hypothesis and revealed the complex interplay of molecular events that led to the emergence of life on Earth.

The process by which cells build proteins using instructions from RNA.

The first living cells likely consisted of self-replicating RNA and the proteins it encoded.

The breakdown of glucose without oxygen, producing lactic acid as a byproduct.

The process of converting light energy into chemical energy, producing glucose from CO2 and H2O and releasing oxygen.

The breakdown of glucose with oxygen, releasing significantly more energy than glycolysis.

A simple, transparent roundworm used extensively in biological research.

A tough, protective outer layer that covers the entire body of C. elegans.

The ability of an organism to produce both male and female gametes, allowing self-fertilization.

The process of cell division and specialization into specific types.

The process of a cell becoming programmed to die.

The complete set of genetic material of an organism.

A gene sequence in one species that is similar to a gene sequence in another species.

A set of chromosomes, found in the cytoplasm of eukaryotes, that carry genetic information for cellular functions.

A small, often urban-dwelling rodent that serves as a vital model organism in life science research.

The ability of an organism to regrow lost or damaged tissues. Zebrafish are known for their remarkable regenerative abilities, particularly in areas like the brain, heart, retina, and ear.

The study of the function of genes in living organisms, often done in the context of development and disease.

A fluorescent protein that emits green light when excited by ultraviolet light. It is often used as a marker in biological research to visualize specific cells or tissues.

A fluorescent protein that emits red light when excited by ultraviolet light. Often used in conjunction with GFP to visualize multiple structures or processes in a single organism.

A database that collects and stores information about zebrafish, including genetic data, developmental information, and experimental results.

A tiny roundworm used in laboratory experiments to study genetics and biology. It's transparent, allowing scientists to easily see the organism's internal processes.

A process that involves introducing double-stranded RNA into an organism to silence specific genes. Used in C. elegans research to study gene function.

The process of programmed cell death that occurs in C. elegans and many other organisms. It's important for development and removing unwanted cells.

A common fruit fly used extensively in genetic research. It's easy to breed and has a short life cycle, making it ideal for studying genetics.

A developmental stage in Drosophila's life cycle where the larva transforms into an adult, similar to a butterfly's pupa stage. The larva's cells are destroyed and adult tissues are formed.

A type of genetic material that carries genetic information similar to DNA, but with a slightly different structure. It can also serve as a genetic blueprint.

A technique used to track biological processes in living organisms, often using fluorescent proteins. C. elegans' transparency makes it ideal for this technique.

A protein that emits light when exposed to specific wavelengths. These proteins are widely used as genetic markers in research.

A type of microscopy that uses the property of fluorescent substances to absorb light from a specific wavelength and emit light at a different wavelength. This allows researchers to visualize and study specific structures and molecules in living cells by labeling them with fluorescent dyes or proteins.

A specialized type of fluorescence microscopy that uses a dichroic mirror to separate excitation and emission light, allowing for the visualization of fluorescently labelled structures within a thicker sample.

The process of fusing a fluorescent protein (like GFP) to another protein of interest. This allows researchers to track and study the tagged protein within a living cell, enabling them to see its location, movement, and interactions with other cellular components.

A type of microscopy where the light passes through a sample and is then interfered by a second beam of light. This interference produces an optical image of the sample, enhancing the contrast between structures with different refractive indices. The result is a 3D-like image.

This type of microscopy uses a specific wavelength of light to illuminate a sample. The light passes through the sample and is then focused by a lens to form an image. This technique provides a basic view of the sample, but it may not be very detailed.

This type of microscopy uses a special phase plate to shift the phase of light passing through different parts of the sample, enhancing the contrast between structures with different refractive indices. This technique allows visualization of transparent structures in living cells.

A compound microscope allows visualization of very small objects. It uses two lenses to magnify the sample, allowing for high magnification and resolution.

Chromatin is a network of DNA and proteins found within the nucleus of a cell. During cell division, chromatin condenses into visible chromosomes.