Biología: Células y Teoría Celular

Introduction

• Living things are organized by cells, which are the fundamental units.
• Growth and development involve increases in cell size, cell number, or both.
• Metabolism is the process organisms use to acquire necessary materials and energy for maintenance, growth, and reproduction.
• Homeostasis involves regulating temperature, pH, water content, and electrolyte balance.
• Response to stimuli is a characteristic of living things.
• Reproduction and heredity involve passing characteristics from one generation to the next.
• Adaptation and evolution are key aspects of living things.
• Cells are the basic functional and structural units of life.
• Unicellular organisms consist of one cell (e.g., prokaryotes).
• Multicellular organisms consist of multiple cells (e.g., eukaryotes).
• Cellular DNA is protected by the nucleus in eukaryotes, while in prokaryotes it is dispersed.
• Cells vary in size and shape, and have different functions.

The Cell

• Cells are the basic units of structure and function in all living organisms.
• Cells are different in size, shape and function.
• Cells have a similar chemical composition, with carbon being the key element for life.
• Cells can be unicellular (one cell) or multicellular (multiple cells).
• Robert Hooke (1665) first observed cells in cork using a microscope.
• The cell theory states that all organisms are composed of cells and that all cells come from pre-existing cells.

Cell Structure and Function

• Cells have different structures and functions, based on their role in the organism.
• Cells have similar chemical compositions.
• Examples of cell components mentioned include cell wall, cell membrane, cytoplasm, nucleus, and other organelles.
• There are several components that can be present, but not all cells will contain all of them.

Biomolecules

• Biomolecules are the molecules that make up living organisms.
• They are composed of different elements, such as carbon, hydrogen, oxygen, nitrogen, and phosphorus.
• Examples of biomolecules include carbohydrates, lipids, proteins, and nucleic acids.
• These have different functions and structures in the cell.

Carbohydrates

• Carbohydrates are an important source of energy for the body.
• Different types of carbohydrates exist, varying in structure and complexity, including monosaccharides, disaccharides, and polysaccharides.
• Monosaccharides are the simplest form of carbohydrates.
• Disaccharides are composed of two monosaccharides linked together.
• Polysaccharides are complex carbohydrates that are composed of many monosaccharides linked together.

Lipids

• Lipids are a diverse group of biomolecules that are insoluble in water.
• Fats, phospholipids, and steroids are important types of lipids.
• Fats are used to store energy, and phospholipids can form membranes.
• Steroids have structural and regulatory roles in the body.

Proteins

• Proteins are essential for many cellular functions, and are polymers of amino acids
• Important functions include structural support, catalyzing reactions , transporting molecules and more.

Nucleic Acids

• Nucleic acids are composed of nucleotides that code genetic information.
• Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are two important types of nucleic acids.
• DNA stores the genetic instructions for building proteins and other molecules.
• RNA helps in the process of protein synthesis.

The Cell Membrane(or Plasmatic Membrane)

• All cells are enclosed by a cell membrane, a thin lipid bilayer that separates the inside of the cell from the outside environment.
• Phospholipids are a major component forming a double layer, with their hydrophobic tails facing inwards and their hydrophilic heads facing outwards.
• Proteins are embedded within the membrane, enabling specific transport of substances into and out of the cell.
• Fluid mosaic model describes the dynamic nature of the cell membrane.
• Cholesterol and carbohydrates are also associated to maintain the cell's structure and function.
• Passive transport processes across the cell membrane include diffusion and osmosis.
• Active transport mechanism moves molecules against their concentration gradient requiring energy from the cell

Cell Organelles

• Cells have many organelles, tiny structures with specific roles within the cell.
• Examples of organelles include mitochondria, ribosomes, Golgi apparatus, and lysosomes.
• Each organelle plays a specialized role in the cell in a wide variety of functions such as respiration, building proteins and digestion.

Cell Division

• Cell division is the process by which a cell divides into two or more daughter cells.
• Mitosis is a type of cell division that produces genetically identical daughter cells.
• Meiosis is a type of cell division that produces genetically diverse daughter cells.

Genetics

• Genetics is the study of heredity and variation in organisms.
• Genes are the basic units of heredity, containing instructions for building proteins.
• Mendel's laws describe the principles of inheritance, including the laws of segregation and independent assortment.
• Different patterns of inheritance exist, aside from Mendelian inheritance.

Evolution

• Evolution is the process by which species change over time.
• Natural selection is the driving force of evolution, favoring traits that increase an organism's fitness.
• Evidence for evolution includes the fossil record, comparative anatomy, and molecular biology.
• Organisms of different types or species can be compared structurally, molecularly and developmentally.

Ecology

• Ecology is the study of the interactions between organisms and their environment.
• Ecosystems are composed of biotic (living) and abiotic (non-living) components.
• Food chains and food webs describe the flow of energy and nutrients within ecosystems.
• Biodiversity and different trophic levels are part of an ecosystem.
• Energy flows through the ecosystem (the sun is the primary energy source), and matter cycles within ecosystems.

Este cuestionario abarca conceptos fundamentales sobre las células eucariotas y procariotas, la teoría celular y las características de los seres vivos. También se exploran los aportes de científicos como Louis Pasteur en la comprensión de la biología. Prepárate para poner a prueba tus conocimientos sobre la vida y la organización celular.