Comprehensive Biology Review: Vertebrates, Cell Division, Botany, Physiology, and Ecology

Vocabulary practice flashcards covering vertebrate classification, cellular reproduction and division, plant morphology and gametogenesis, nervous and endocrine systems, and population ecology.

Placoderms (Placodermos)

A group of extinct fossil fish from the Paleozoic era characterized by being small and strange.

Agnatha (Agnatos / Ciclóstomos)

Aquatic jawless vertebrates whose mouth functions as a suction cup with teeth applied to prey skin; surviving groups include hagfish (mixinos) and lampreys (lampreas).

Hagfish (Mixinos)

Jawless vertebrates that inhabit temperate waters in both hemispheres as well as colder tropical waters.

Lampreys (Lampreas)

Jawless vertebrates that lay their eggs either in sea beds or in rivers.

Chondrichthyes (Condroíctios)

Aquatic vertebrates with a cartilaginous skeleton, paired fins, and gill respiration; predominantly marine predators and scavengers with internal fertilization, oviparous reproduction (or ovoviviparous/viviparous in some sharks).

Osteichthyes (Osteíctios)

Bony fish with paired or unpaired fins that are naked or scale-covered; they easily adapt to environments and exhibit external fertilization with oviparous reproduction.

Dipnoi (Dipnoos)

A group of fish characterized by having lungs (peces pulmonados).

Gymnophiona / Caecilians (Ápodos o cecilias)

Amphibians characterized by a long, cylindrical body, lack of limbs, and blindness.

Anura (Anuros)

Amphibians that lack a tail in their adult state, comprising toads and frogs.

Urodela (Urodelos)

Tailed amphibians comprising newts (tritones) and salamanders.

Reptiles

Amniote vertebrates incapable of regulating their own body temperature, covered in an exoskeleton of horny epidermal scales, with pulmonary respiration, separate sexes, and mostly oviparous reproduction (with occurrences of vivipary and ovovivipary).

Aves (Birds)

Amniote, homeothermic vertebrates covered in feathers, possessing pulmonary respiration, a lightweight body, and a toothless (or rarely toothed) beak.

Prototheria (Proterios)

A class of mammals that includes monotremes such as the platypus (ornitorrinco) and echidna (equidna).

Eutheria (Euterios)

Placental mammals whose developing young are nourished via the maternal placenta.

Binary Fission (Bipartición)

An asexual reproductive process in unicellular organisms (such as bacteria, amoebas, and paramecia) where a single parent cell divides exactly in half to produce two identical daughter cells of equal size.

Budding (Gemación)

An asexual reproduction mode where a small bud forms on the parent cell and detaches as a smaller daughter cell that later grows to adult size, characteristic of yeast.

Sporulation (Esporulación)

An asexual reproduction process where the parent nucleus divides repeatedly into multiple nuclei ($2, 4, 8, 16, 32$, etc.), which surround themselves with cytoplasm and a membrane before being released as spores, as in Plasmodium vivax.

Fase G1 (Gap 1)

The interphase stage dedicated to organelle synthesis and cellular growth to prepare components for distribution to future daughter cells.

Fase S (Síntesis)

The cell cycle phase during interphase where the exact replication of DNA and chromosomal genetic material takes place.

Fase G2 (Gap 2)

The final stage of interphase where the cell makes final preparations and synthesizes substances required to initiate nuclear division.

Centromere (Centrómero)

The constricted chromosomal region that holds two sister chromatids together and divides the chromosome into two arms.

Kinetochore (Cinetocoro)

A specialized protein structure located at each centromere that is essential for chromosome movement during cell division.

Diploid Cells ($2n$)

Cells containing pairs of homologous chromosomes (one maternal and one paternal), totaling $46$ chromosomes or $23$ pairs in humans.

Haploid Cells ($n$)

Cells containing only a single chromosome from each homologous pair, representing half the total chromosome count ($23$ chromosomes in humans).

Prophase (Profase)

The first phase of mitosis where chromatin condenses into visible double-chromatid chromosomes, the nucleolus and nuclear envelope disassemble, and the mitotic spindle forms.

Metaphase (Metafase)

The mitotic stage where maximally condensed chromosomes align along the cell's center to establish the metaphase or equatorial plate.

Anafase (Anaphase)

The stage of mitosis where sister chromatids are pulled apart at the centromere and dragged toward opposite cellular poles.

Telophase (Telofase)

The final mitotic phase where new nuclear envelopes assemble around separated sets of decondensing chromosomes and nucleoli reappear.

Animal Cytokinesis

Cytoplasmic division achieved through furrowing/constriction via a contractile ring made of actin and myosin filaments.

Plant Cytokinesis

Cytoplasmic division occurring through the centrifugal formation of an internal cell plate (placa celular) derived from Golgi vesicles and polar microtubules.

Crossing Over (Entrecruzamiento)

The reciprocal exchange of genetic material between paired homologous chromosomes (bivalents) during prophase I of meiosis.

Gynoecium (Gineceo / Pistilo)

The female reproductive organ of a flower composed of carpels, divided into the stigma (pollen reception), style (conduction tube), and ovary (ovule-bearing chamber).

Androecium (Androceo / Estambres)

The male reproductive organ of a flower composed of stamens, each containing a filament and an anther with thecae and pollen sacs.

Gymnosperms (Gimnospermas)

Woody plants (such as pines, cypresses, and firs) with inconspicuous unisexual cones (strobili) bearing naked seeds exposed on bracts without an enclosing fruit.

Angiosperms (Angiospermas)

Vascular seed plants possessing typically showy, complete flowers and seeds enclosed within a protective fruit developed from the ovary.

Microsporogenesis

The production of haploid pollen grains inside anther sacs by meiosis, followed by a mitotic division yielding a vegetative nucleus and a generative nucleus.

Embryo Sac (Saco Embrionario)

The mature eight-nucleate female gametophyte of angiosperms containing $1$ egg cell (oosfera), $2$ synergids, $3$ antipodals, and $2$ polar nuclei.

Endosperm (Endospermo)

The nutritional reserve tissue of a seed rich in carbohydrates, starch, lipids, or proteins that sustains the embryo during germination.

Monocotyledons vs. Dicotyledons

Taxonomic divergence where monocots have $1$ cotyledon, parallel venation, scattered vascular bundles, trimerous floral parts, and $1$ pollen pore; dicots have $2$ cotyledons, reticulate venation, ring-arranged bundles, tetramerous/pentamerous parts, and $3$ pores.

Drupe (Drupa)

A fleshy simple fruit with a stony, lignified endocarp (pit or stone) enclosing the seed, seen in peaches, plums, olives, avocados, and mangoes.

Berry (Baya)

A fleshy simple fruit whose pericarp is soft and fleshy throughout, such as a tomato or grape.

Central Nervous System (SNC)

The primary nervous division responsible for perceiving, generating, and transmitting nerve impulses.

Peripheral Nervous System (SNP)

Nerves and neurons extending throughout the body that coordinate, regulate, and integrate internal organs; divided into somatic and autonomic systems.

Autonomic Nervous System (Sistema Nervioso Autónomo)

The peripheral branch subdivided into sympathetic and parasympathetic divisions that coordinates involuntary bodily actions.

Hormones (Hormonas)

Chemical substances synthesized and secreted by endocrine organs that circulate through the bloodstream to regulate target systems.

Pituitary Gland (Hipófisis / Glándula Pituitaria)

The master endocrine gland of the human body that controls the secretions of other endocrine glands.

Thyroid Gland (Tiroides)

A butterfly-shaped gland located below the cartilage that produces the hormones thyroxine and triiodothyronine.

Parathyroid Glands (Paratiroides)

Two pairs of small glands located beside the thyroid lobes that regulate blood levels.

Adrenal Glands (Glándulas Suprarrenales)

Endocrine glands situated atop the kidneys that produce adrenaline and noradrenaline.

Gonads (Gónadas)

The primary sex glands: ovaries (which produce progesterone alongside estrogens) and testes (which secrete testosterone).

Ecological Individual (Individuo)

A single organism exhibiting the biological characteristics typical of its species.

Population (Población)

A collection of living organisms or individuals belonging to the exact same species.

Ecological Community (Comunidad)

An ecological assemblage formed by a collection of interacting populations.

Ecological Niche (Nicho Ecológico)

The specific functional role or activity performed by an individual within an ecological community.

Biocenosis (Biocenosis)

The assemblage of all living beings that coexist and interact within a shared physical environment.

Population Density Formula

The ecological calculation given by $\text{Densidad} = \frac{\text{Población}}{\text{Superficie}}$, where $\text{Población} = \text{Densidad} \times \text{Superficie}$ and $\text{Superficie} = \frac{\text{Población}}{\text{Densidad}}$.

Trophic Networks (Redes Tróficas)

The complete assemblage of all interconnected food chains present within an ecosystem.

Pyramid of Numbers (Pirámide de Números)

An ecological pyramid displaying the absolute quantity of individual organisms occupying each trophic level.

Pyramid of Biomass (Pirámide de Biomasa)

An ecological pyramid illustrating the total dry mass or living weight present across each successive trophic level.

Pyramid of Energy (Pirámide de Energía)

An ecological pyramid illustrating the quantity and flow of energy between different trophic levels.

Threatened Paraguayan Fauna

Animal species under threat in Paraguay, including yaguareté, tatu guasu, guyra campana, papagayo azul, and guasu puku.

Threatened Paraguayan Flora

Plant species designated as threatened in Paraguay, including arary, kun'y, and yvyra piriri guasu.