Untitled Deck Flashcards
What is a cell?
The basic unit of life, capable of performing all life processes.
What is the cell membrane?
A semi-permeable barrier that surrounds the cell, controlling the movement of substances in and out.
What is cytoplasm?
The jelly-like fluid inside the cell that contains organelles and is the site of many metabolic processes.
What is the nucleus?
The organelle that contains the cell’s genetic material (DNA) and controls cellular activities.
What are mitochondria?
The organelles responsible for producing ATP through aerobic respiration, often referred to as the powerhouse of the cell.
What is a chloroplast?
The organelle in plant cells that conducts photosynthesis, converting light energy into chemical energy.
What is a ribosome?
The cellular structure that synthesizes proteins by translating mRNA into polypeptide chains.
What is the endoplasmic reticulum (ER)?
A network of membranes involved in the synthesis and transport of proteins (rough ER) and lipids (smooth ER).
What is the Golgi apparatus?
The organelle responsible for modifying, sorting, and packaging proteins and lipids for secretion or use within the cell.
What is a lysosome?
A membrane-bound organelle containing digestive enzymes that break down waste materials and cellular debris.
What is diffusion?
The passive movement of molecules from an area of higher concentration to an area of lower concentration.
What is osmosis?
The diffusion of water molecules across a selectively permeable membrane.
What is active transport?
The process of moving substances across a cell membrane against their concentration gradient, requiring energy (ATP).
What is homeostasis?
The maintenance of a stable internal environment within an organism despite external changes.
What is cell respiration?
The process of converting biochemical energy from nutrients into ATP, involving glycolysis, the Krebs cycle, and oxidative phosphorylation.
What is photosynthesis?
The process by which green plants, algae, and some bacteria convert light energy into chemical energy stored in glucose.
What is metabolism?
The sum of all chemical reactions occurring within a cell, including catabolism (breaking down molecules) and anabolism (building up molecules).
What is an enzyme?
A biological catalyst that speeds up chemical reactions in the cell without being consumed in the process.
What is a substrate?
The reactant molecule upon which an enzyme acts.
What is a product?
The substances formed as a result of a chemical reaction catalyzed by an enzyme.
What is the plasma membrane?
The outer boundary of the cell, composed of a lipid bilayer that regulates what enters and exits the cell.
What is the cytoskeleton?
A network of protein filaments and tubules that provide structural support, shape, and movement to the cell.
What are centrioles?
Cylindrical structures involved in cell division, helping to organize the mitotic spindle.
What is a vesicle?
A small membrane-bound sac that transports substances within the cell or to the cell membrane for secretion.
What is apoptosis?
Programmed cell death, a controlled process that removes damaged or unnecessary cells.
What is a stem cell?
Undifferentiated cells that have the potential to develop into various cell types in the body.
What is gene expression?
The process by which the information encoded in a gene is used to produce a functional gene product, usually a protein.
What is transcription?
The first step of gene expression, where a specific segment of DNA is copied into mRNA.
What is translation?
The process by which ribosomes synthesize proteins based on the sequence of mRNA.
What is a codon?
A sequence of three nucleotides in mRNA that specifies a particular amino acid.
What is an anticodon?
A sequence of three nucleotides in tRNA that pairs with a corresponding codon in mRNA during protein synthesis.
What is a hormone?
A signaling molecule produced by glands that regulate various physiological processes in the body.
What is signal transduction?
The process by which a cell responds to external signals through a series of molecular events, leading to a cellular response.
What is endocytosis?
The process by which cells internalize substances from their external environment by engulfing them in a vesicle.
What is exocytosis?
The process by which cells expel substances from within the cell to the outside environment using vesicles.
What is facilitated diffusion?
The process of transporting substances across a cell membrane with the help of membrane proteins, without the use of energy.
What is a concentration gradient?
The difference in concentration of a substance across a space or membrane, driving diffusion.
What is the nucleolus?
A structure within the nucleus where ribosomal RNA (rRNA) is produced and assembled into ribosome subunits.
What is the cell cycle?
The series of events that a cell goes through as it grows and divides, including interphase and mitosis.
What is mitosis?
The process of cell division that results in two genetically identical daughter cells.
What is chlorophyll?
The green pigment found in chloroplasts that absorbs light energy for photosynthesis.
What is ATP (Adenosine Triphosphate)?
The primary energy carrier in cells, providing energy for various cellular processes.
What is the electron transport chain?
A series of protein complexes in the inner mitochondrial membrane that transfer electrons and pump protons, generating ATP.
What is anaerobic respiration?
A type of respiration that occurs without oxygen, producing energy and byproducts such as lactic acid or ethanol.
What is aerobic respiration?
The process of producing cellular energy in the presence of oxygen, resulting in carbon dioxide and water as byproducts.
What is a metabolic pathway?
A series of chemical reactions occurring within a cell, leading to the conversion of substrates into products.
What is substrate-level phosphorylation?
The direct synthesis of ATP from ADP and a phosphorylated intermediate in a metabolic pathway.
What is fermentation?
A metabolic process that converts sugars to acids, gases, or alcohol in the absence of oxygen, typically used by yeast and some bacteria.
What is the genetic code?
The set of rules by which information encoded in genetic material is translated into proteins.
What is a transgenic organism?
An organism that has been genetically modified to contain a gene from another species.
What is epigenetics?
The study of changes in gene expression that do not involve alterations to the underlying DNA sequence.
What is a mutagen?
An agent, such as a chemical or radiation, that causes genetic mutation.
What is chromatin?
The material of which the chromosomes are composed, consisting of DNA and proteins, primarily histones.
What is a histone?
A protein that helps package DNA into a compact, organized structure known as chromatin.
What is a chromosome?
A structure made of DNA and proteins that carries genetic information; humans typically have 46 chromosomes.
What is glycolysis?
The metabolic pathway that breaks down glucose into pyruvate, producing ATP and NADH.
What is the Krebs cycle (Citric Acid Cycle)?
A series of chemical reactions used by aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats, and proteins.
What is a signal molecule?
A molecule that transmits a signal to a cell, influencing its activity or behavior.
What is a receptor protein?
A protein that binds to a specific ligand, initiating a cellular response.
What is cell specialization (differentiation)?
The process by which a less specialized cell becomes a more specialized cell type, enabling it to perform a specific function.
What is a tissue?
A group of cells that work together to perform a specific function.
What is an organ?
A structure composed of different types of tissues that work together to perform a specific function in an organism.
What is an organ system?
A group of organs that work together to carry out complex functions necessary for survival.
What is stem cell differentiation?
The process by which stem cells develop into specialized cell types with distinct functions.
What are proteins?
Large biomolecules made up of amino acids that perform a variety of functions in the cell, including catalyzing reactions and providing structural support.
What are amino acids?
The building blocks of proteins, linked together by peptide bonds.
What is a peptide bond?
The chemical bond formed between two amino acids during protein synthesis.
What is a polypeptide?
A chain of amino acids linked by peptide bonds, which folds to form a functional protein.
What is a nucleotide?
The basic structural unit of DNA and RNA, consisting of a sugar, phosphate group, and nitrogenous base.
What is DNA replication?
The process by which DNA makes a copy of itself prior to cell division.
What is semi-conservative replication?
The method of DNA replication in which each new DNA molecule consists of one original strand and one newly synthesized strand.
What are mutations?
Permanent alterations in the DNA sequence that can affect gene function and lead to variations in traits.
What is RNA (Ribonucleic Acid)?
A nucleic acid that plays a central role in protein synthesis and gene regulation.
What is mRNA (Messenger RNA)?
A type of RNA that carries genetic information from the DNA in the nucleus to the ribosomes in the cytoplasm for protein synthesis.
What is tRNA (Transfer RNA)?
A type of RNA that transports amino acids to the ribosome during protein synthesis, matching them to the appropriate codon on the mRNA.
What is rRNA (Ribosomal RNA)?
A type of RNA that makes up the structural and functional components of ribosomes.
What are transcription factors?
Proteins that bind to specific DNA sequences, regulating the transcription of genetic information from DNA to mRNA.
What is gene regulation?
The mechanisms that cells use to increase or decrease the production of specific gene products (proteins).
What is genetic engineering?
The manipulation of an organism’s DNA to alter its characteristics, often involving the addition of foreign DNA.
What is cell signaling?
The process by which cells communicate with each other to coordinate their activities and respond to changes in their environment.
