Organisms: Structure, Processes, Heredity, and Biological Evolution Flashcards

A comprehensive set of vocabulary flashcards covering biochemistry, cell biology, genetics, and reproduction based on the 6th-semester biology lecture exam transcript.

Lipids

A varied group of molecules characterized by being insoluble in water but soluble in low-polarity organic solvents like ether, chloroform, and benzene.

Saturated Fatty Acids

Fatty acids without double bonds, such as palmitic acid found in coconut/palm oil and red meat, or stearic acid found in animal lard.

Unsaturated Fatty Acids (Oils)

Fatty acids containing double bonds, typically obtained from seeds (sunflower, corn) or fruits like olives and avocados.

Phospholipids

Complex lipids that form part of cellular structures.

Prostaglandins

Molecules with hormonal effects that participate in regulating body temperature and blood pressure, and cause smooth muscle contraction.

Terpenes

Also known as essential plant oils, these are used for their aromatic qualities and flavors in herbalism and industry.

Peptide Bond

The chemical bond that links amino acids together to form proteins.

Essential Amino Acids

Amino acids that are indispensable for humans but cannot be synthesized by the body, thus requiring dietary intake.

Primary Structure (Protein)

The linear sequence or order in which amino acids are placed in a protein.

Enzymes (Biological Catalysts)

Special proteins within cells that act as biological catalysts to regulate chemical reactions.

Binary Fission (Bipartición)

Asexual reproduction in unicellular organisms where an organism creates a genetically identical copy of itself.

Sporulation

A form of reproduction involving spores wrapped in protective membranes, common in fungi, mosses, and ferns to survive environmental changes.

Budding (Gemación)

A type of reproduction where a bud grows on the parental cell, consumes nutrients from it, and eventually separates as an independent organism; common in yeast.

Parthenogenesis

The development of a new organism from an unfertilized egg, identified in species like the water flea.

Monotremes

A division of mammals defined by their specific method of embryonic development (egg-laying).

Genetic Code

The correspondence between codons in RNA (or DNA) and specific amino acids in a protein.

Codon

A sequence of three nucleotides located in messenger RNA (mRNA).

S Phase (Synthesis)

The stage of the cell cycle during which DNA replication occurs.

Chromatin

The form that genetic material takes during interphase before it condenses into chromosomes.

Helicase

The enzyme that separates DNA strands by breaking the hydrogen bonds during the replication process.

Okazaki Fragments

Discontinuous segments of DNA synthesized on the lagging strand (cadena atrasada) during replication.

SSB Proteins

Single-strand binding proteins that stabilize monocatenary DNA to prevent it from renaturing or forming secondary structures during replication.

Cytokinesis

The phase of cell division where a ring of actin protein contracts to divide the cytoplasm into two daughter cells.

Apoptosis

The process defined as programmed cell death.

Abiotic Synthesis Theory

The theory proposing that life originated through chemical and prebiological evolution in a primitive atmosphere containing methane, ammonia, hydrogen, and water vapor.

Endosymbiotic Theory

Theory suggesting eukaryotic complexity arose from cooperation between simple organisms, with mitochondria and chloroplasts serving as primary evidence.

Irritability

A characteristic of living things defined by the ability to respond to stimuli, such as a plant growing toward sunlight.

Homeostasis

The cellular function of maintaining internal stability, especially in environments with scarce nutrients.

Passive Transport

Cellular transport that occurs according to the concentration gradient without the expenditure of chemical energy ($ATP$).

Active Transport

Transport that requires an investment of chemical energy ($ATP$) to move substances against their concentration gradient.

Phagocytosis

A type of endocytosis where a cell forms a membranous sac to envelop and internalize solid particles, such as a white blood cell destroying bacteria.

Anabolism

The constructive metabolic pathway where complex molecules are synthesized from simple ones.

Catabolism

The metabolic pathway focused on the breakdown of molecules to release energy.

Fermentation

A metabolic process that obtains energy from glucose without the use of oxygen ($O_2$).

Glycolysis

The metabolic stage that occurs in the cytoplasm and serves as the initial step for breaking down glucose.

Krebs Cycle

The metabolic stage involving the oxidation of pyruvic acid and ending with the formation of oxaloacetic acid.

Carboxyl Group

A polar functional group common in fatty acids and amino acids that behaves as an acid.

Phosphate Group

A functional group found in nucleic acids and lipids that acts as the primary energy carrier in $ATP$ molecules.

Chitin

A polysaccharide that forms the exoskeletons of insects.

Glycogen

The energy reserve polysaccharide stored in the liver of animals.