Inglés para Biología: Vocabulario y Frases Esenciales

"organelle"

A specialised subunit within a cell that carries out a specific function, analogous to an organ in the body.

"The mitochondria is the organelle responsible for producing most of the cell's ATP through cellular respiration."

"cell membrane"

The selectively permeable phospholipid bilayer that encloses the cell, regulating what enters and exits.

"Oxygen diffuses freely across the cell membrane because it is a small, non-polar molecule."

"mitosis"

The process of cell division that produces two genetically identical daughter cells, used for growth and repair.

"After the wound healed, mitosis replaced the damaged tissue with new, identical cells."

"meiosis"

A type of cell division that produces four genetically diverse haploid gametes from a single diploid cell.

"Meiosis introduces genetic variation through crossing over during the formation of sperm and egg cells."

"endocytosis"

The process by which a cell engulfs external material by wrapping the cell membrane around it to form a vesicle.

"The immune cell used endocytosis to engulf and destroy the invading bacterium."

"apoptosis"

Programmed cell death, a controlled process by which damaged or redundant cells are systematically eliminated.

"Apoptosis is essential during embryonic development to sculpt the fingers from paddle-shaped limb buds."

"cytoplasm"

The gel-like fluid that fills the cell interior, suspending organelles and serving as the medium for cellular reactions.

"Glycolysis occurs in the cytoplasm, breaking glucose into pyruvate to release energy."

"ribosome"

A molecular machine composed of RNA and protein that reads messenger RNA and synthesises polypeptide chains.

"Ribosomes on the rough endoplasmic reticulum translate mRNA into proteins destined for secretion."

"genotype"

The complete set of genetic instructions carried by an organism, or the specific alleles it possesses for a given trait.

"Although both plants had a green phenotype, their genotypes differed — one was homozygous and the other heterozygous."

"phenotype"

The observable physical and biochemical characteristics of an organism resulting from the interaction of its genotype and the environment.

"Identical twins share the same genotype but may develop different phenotypes due to environmental factors."

"allele"

One of two or more alternative forms of a gene that can occupy the same position on a chromosome.

"Mendel showed that the dominant allele for seed colour masked the recessive allele in heterozygous pea plants."

"transcription"

The process by which the information in a DNA strand is copied into a complementary messenger RNA molecule.

"RNA polymerase binds to the promoter region and begins transcription of the gene into pre-mRNA."

"translation"

The process by which ribosomes decode messenger RNA to assemble a sequence of amino acids into a protein.

"During translation, each codon on the mRNA specifies a particular amino acid to be added to the growing chain."

"CRISPR-Cas9"

A precise gene-editing technology that uses a guide RNA to direct the Cas9 enzyme to cut DNA at a specific location.

"Researchers used CRISPR-Cas9 to knock out the gene responsible for the inherited metabolic disorder."

"epigenetics"

The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence.

"Epigenetics research has shown that diet during pregnancy can alter gene expression in offspring."

"polymerase chain reaction (PCR)"

A laboratory technique that amplifies a specific segment of DNA millions of times to produce enough for analysis.

"PCR was used to detect the presence of the pathogen's DNA in environmental water samples."

"natural selection"

The process by which individuals with heritable traits that improve survival and reproduction pass those traits on more often.

"Natural selection favoured the peppered moth's darker form during the Industrial Revolution when soot darkened trees."

"carrying capacity"

The maximum population size that an environment can sustainably support given available resources.

"The deer population crashed once it exceeded the forest's carrying capacity and exhausted the food supply."

"niche"

The ecological role and position a species occupies in its environment, including its habitat, diet, and interactions.

"By occupying different niches, the warbler species avoided direct competition despite sharing the same forest."

"trophic level"

A position in a food chain defined by the number of energy-transfer steps to that organism from the primary producer.

"Energy is lost at each trophic level, so ecosystems can support far fewer top predators than herbivores."

"symbiosis"

A close and long-term biological interaction between two different species, which can be mutualistic, commensal, or parasitic.

"The clownfish and sea anemone demonstrate mutualistic symbiosis, each providing benefits to the other."

"adaptive radiation"

The rapid evolution of multiple species from a single ancestor, each adapted to a different ecological niche.

"Darwin's finches in the Galapagos are a classic example of adaptive radiation from a common ancestor."

"keystone species"

A species that has a disproportionately large effect on its ecosystem relative to its abundance.

"Sea otters are a keystone species; their removal causes kelp forest ecosystems to collapse through sea urchin overpopulation."

"biogeography"

The study of the distribution of species and ecosystems in geographic space and through geological time.

"Biogeography explains why marsupials are concentrated in Australia due to continental drift and isolation."

"homeostasis"

The self-regulating process by which organisms maintain stable internal conditions such as temperature and pH.

"Sweating and vasodilation are homeostatic mechanisms that prevent the body from overheating during exercise."

"negative feedback"

A regulatory mechanism in which a change in a variable triggers a response that reverses the change and restores balance.

"The negative feedback loop of insulin and glucagon maintains blood glucose within a narrow range."

"osmoregulation"

The active regulation of water and solute concentrations in body fluids to maintain optimal cellular function.

"Freshwater fish face constant water influx and use kidneys and gills for effective osmoregulation."

"action potential"

A rapid, temporary electrical signal propagated along a neuron's membrane, triggered by depolarisation above a threshold.

"When the receptor potential exceeds the threshold, an action potential fires and travels along the sensory neuron."

"hormonal regulation"

The use of chemical messengers secreted by endocrine glands to coordinate physiological processes across the body.

"Hormonal regulation by thyroid hormones controls metabolic rate in nearly every cell of the body."

"gas exchange"

The diffusion of oxygen from the environment into the blood and carbon dioxide from the blood into the environment.

"The alveoli's large surface area and thin walls maximise the efficiency of gas exchange in the lungs."

"peristalsis"

The rhythmic, wave-like muscle contractions that propel food through the digestive tract.

"Peristalsis moves the bolus from the oesophagus to the stomach in a coordinated muscular sequence."

"synaptic transmission"

The process by which a nerve signal is passed from one neuron to another across a synapse via neurotransmitters.

"Synaptic transmission at the neuromuscular junction triggers muscle fibre contraction when acetylcholine is released."

"pathogen"

A microorganism — such as a bacterium, virus, fungus, or parasite — that causes disease in a host.

"The pathogen responsible for tuberculosis is Mycobacterium tuberculosis, a slow-growing bacterium."

"antibody"

A Y-shaped protein produced by B cells that binds specifically to an antigen to neutralise it or mark it for destruction.

"The antibody produced after vaccination binds to the viral surface protein and blocks cell entry."

"antigen"

A molecule, typically on the surface of a pathogen, that the immune system recognises as foreign and mounts a response against.

"The antigen on the bacterium's cell wall triggered the activation of T cells and B cells in the lymph node."

"virulence"

The degree of pathogenicity of a microorganism — its capacity to infect, cause disease, and evade host defences.

"Scientists studied what genetic mutations increased the virulence of the influenza strain."

"culture medium"

A nutrient-rich liquid or solid substrate used to grow and maintain microorganisms in the laboratory.

"The bacteria were streaked onto a culture medium containing blood agar to identify haemolytic activity."

"innate immunity"

The non-specific, rapid first line of immune defence that responds immediately to any pathogen without prior exposure.

"Macrophages and neutrophils are key cells of the innate immunity system, engulfing pathogens on first contact."

"adaptive immunity"

The specific, memory-forming branch of the immune system that tailors its response to particular antigens after exposure.

"Adaptive immunity produced memory B cells that enabled a faster, stronger response on second infection."

"antibiotic resistance"

The ability of bacteria to survive and multiply in the presence of an antibiotic that would normally kill or inhibit them.

"Overuse of broad-spectrum antibiotics has accelerated the evolution of antibiotic resistance in clinical settings."

"hypothesis"

A testable, falsifiable prediction about the relationship between variables, based on existing knowledge.

"The researchers stated their hypothesis: increasing nitrogen concentration will accelerate plant growth rate."

"control group"

A group in an experiment that is not subjected to the variable being tested, used as a baseline for comparison.

"The control group received a saline injection while the experimental group received the drug candidate."

"peer review"

The evaluation of scientific work by other qualified experts in the same field before it is published.

"The study's methodology was scrutinised during peer review, leading the authors to revise their statistical analysis."

"confounding variable"

An extraneous factor that correlates with both the independent and dependent variable, potentially distorting results.

"The researchers controlled for diet as a confounding variable when studying exercise and bone density."

"western blot"

An analytical technique used to detect specific proteins in a sample by separating them with gel electrophoresis and labelling with antibodies.

"The western blot confirmed that the knockout cells no longer expressed the target protein."

"statistical significance"

A result that is unlikely to have occurred by chance, typically indicated by a p-value below 0.05.

"The difference in survival rates between the two treatment groups reached statistical significance (p = 0.03)."

"in vitro"

An experiment or process performed outside a living organism, in a controlled laboratory environment such as a cell culture.

"The compound showed promising anti-tumour activity in vitro, but the in vivo results were less conclusive."

"flow cytometry"

A laser-based technique for counting, sorting, and characterising cells or particles in a fluid by their physical and chemical properties.

"Flow cytometry was used to quantify the proportion of activated T cells in blood samples from each patient."