Explanation: In anisogamous reproduction, the female gamete is larger and typically immotile, while the male gamete is smaller and motile.

Explanation: Oogamy is indeed a form of anisogamy characterized by a large, immotile female gamete (ovum) and a small, motile male gamete (sperm).

Explanation: The evolution of anisogamy is theorized to provide advantages in both gamete survival (larger gametes) and fertilization efficiency (smaller, motile gametes).

Explanation: Anisogamy appears to have evolved multiple times independently from isogamy.

Explanation: Sexual reproduction typically involves two parents and results in genetically diverse offspring, unlike asexual reproduction.

Explanation: Heterogamous reproduction refers to systems where gametes differ in size or form, such as anisogamy and oogamy.

Explanation: Gametes are specialized sex cells that fuse during fertilization to form a zygote, initiating new organism development.

Explanation: Anisogamous systems are characterized by gametes that differ in size, with the female gamete being larger.

Explanation: Heterogamy signifies reproductive systems where gametes exhibit differences in size or morphology.

Explanation: In anisogamy, the female gamete (ovum) is larger and typically immotile, while the male gamete (sperm) is smaller and motile.

Explanation: The primary distinction is that sexual reproduction involves gamete fusion and generates genetic diversity, whereas asexual reproduction involves a single parent and produces genetically identical offspring.

Explanation: The term "heterogamous" signifies reproductive systems where the gametes involved exhibit differences in size or form.

Explanation: The biological definition of a female organism centers on its ability to produce ova, which are the larger gametes essential for sexual reproduction.

Explanation: Mammary glands are a defining characteristic of mammals, typically more developed in females for milk production.

Explanation: Monotreme mammals, such as the platypus, are an exception as their females lay eggs.

Explanation: Oogenesis is the biological process of producing ova (egg cells), not sperm.

Explanation: Mammary glands are a key mammalian trait for nourishing young, and they are generally more developed in females.

Explanation: Ova serve as the female gametes that are fertilized by male gametes to initiate the development of a new organism.

Explanation: Feminization denotes the development of female characteristics or a transition towards a female state.

Explanation: The fundamental biological definition of a female organism is its capacity to produce ova, the larger gametes involved in sexual reproduction.

Explanation: The presence of mammary glands, used for nourishing offspring, is a defining characteristic of female mammals.

Explanation: Monotremes, such as the platypus and echidnas, are mammals whose females lay eggs.

Explanation: Oogenesis is the biological process by which ova, or egg cells, are produced within the female reproductive system.

Explanation: The primary function of ova is to undergo fertilization by male gametes (sperm) to initiate the development of a new organism.

Explanation: In most mammals, females are XX and males are XY.

Explanation: This process, known as X-inactivation, occurs randomly in placental mammals to regulate gene dosage from the two X chromosomes.

Explanation: Birds and some reptiles utilize the ZW system, where females are ZW and males are ZZ, the reverse of the mammalian XY system.

Explanation: Jost's experiments indicated that mammalian development defaults to female in the absence of testicular hormones, though recent studies have begun to question this.

Explanation: Sex determination can be influenced by genetic factors, environmental conditions, or natural changes during an organism's life.

Explanation: In the ZW system, males are ZZ, and females are ZW.

Explanation: Temperature-dependent sex determination is observed in species such as crocodilians, not typically fish.

Explanation: *Wolbachia* can be crucial for female sexual viability and influence sex determination in certain arthropod species.

Explanation: Recognizing sex as a biological variable means understanding its impact on biological processes and research findings.

Explanation: In the ZW system, females are ZW and males are ZZ.

Explanation: The Y chromosome in mammals primarily determines maleness, not femaleness.

Explanation: Certain species, such as some gobies, exhibit sequential hermaphroditism, where sex can change naturally during their lifespan in response to environmental or social cues.

Explanation: While the X chromosome carries essential genes, it is typically inactivated randomly in *most* cells, not all cells, in female mammals.

Explanation: Typically, female mammals possess two X chromosomes (XX), while males possess one X and one Y chromosome (XY).

Explanation: In placental mammals, one of the two X chromosomes in females undergoes random inactivation in most cells.

Explanation: In birds and some reptiles, the female sex is typically heterozygous, possessing ZW sex chromosomes.

Explanation: Alfred Jost's experiments suggested that mammalian sexual development defaults to female in the absence of specific male hormonal influences.

Explanation: An organism's sex can be determined by genetic makeup, environmental factors, or through natural changes occurring during its life cycle.

Explanation: In the ZW sex-determination system, males possess two Z chromosomes (ZZ).

Explanation: In crocodilians, the temperature during egg incubation is a critical environmental factor that determines the sex of the offspring.

Explanation: *Wolbachia* bacteria are essential for female sexual viability and influence sex determination in numerous arthropod species.

Explanation: Acknowledging "sex as a biological variable" highlights its influence on biological processes, health outcomes, and research findings.

Explanation: Species with distinct males and females are classified as gonochoric in animals and dioecious in seed plants and dioicous in cryptogams.

Explanation: Gynodioecy is characterized by the coexistence of female individuals and hermaphrodites within a species.

Explanation: Trioecy describes a sexual system where females, males, and hermaphrodites coexist within the same species.

Explanation: Dioecy refers to species with separate male and female individuals, while gynodioecy involves females and hermaphrodites.

Explanation: Dioecy is a sexual system where individuals within a species are distinctly either male or female.

Explanation: Trioecy is a sexual system characterized by the coexistence of female individuals, males, and hermaphrodites within the same species.

Explanation: While one historical speculation links the female symbol (♀) to Venus's mirror, modern scholarly consensus suggests it originates from contractions in Greek script of planetary names.

Explanation: The English word "female" originates from the Latin *femella*, meaning "woman," not from *masculus*.

Explanation: The term "female" has been used as a noun and adjective since the 14th century, initially referring to humans, with its application expanding to non-human organisms later.

Explanation: By the late 19th century, the usage of "female" as a noun for humans began to be considered disparaging, partly due to its association with non-human animals.

Explanation: In the 21st century, the noun "female" is primarily used for non-human animals or in impersonal technical contexts for humans, not informal social contexts.

Explanation: The adjective "female" remains commonly used when sex is relevant to the context, such as in discussions of "female athletes."

Explanation: Biological sex and gender identity are distinct concepts; sex refers to biological characteristics, while gender encompasses identity and expression.

Explanation: In connectors and fasteners, the "female" component is the socket or receptacle designed to receive the "male" part.

Explanation: While "female" can refer to biological sex, it can also be used socially, and biological sex is distinct from gender identity.

Explanation: The spelling change in the late 14th century was to parallel "male," not due to etymological reasons.

Explanation: The Venus symbol (♀) universally represents the female sex in biology.

Explanation: While "female" can denote biological sex, it is also used socially, and biological sex is distinct from gender identity.

Explanation: Modern scholarship suggests the female symbol (♀) originates from Greek script contractions, not definitively from Venus's mirror.

Explanation: Modern scholarship indicates the biological symbol for the female sex (♀) originates from Greek script contractions of planetary names associated with Venus.

Explanation: The English word "female" derives from the Latin *femina* ('woman'), with its spelling later altered in the 14th century to resemble "male."

Explanation: The term "female" expanded from its initial 14th-century human-specific usage to include non-human organisms approximately a century later, in the 15th century.

Explanation: By the late 19th century, the noun "female" began to be perceived as potentially disparaging, partly because its usage extended to non-human animals.

Explanation: Contemporary usage of the noun "female" predominantly applies to non-human animals or in impersonal, technical contexts for humans.

Explanation: The adjective "female" remains common when sex is contextually relevant, such as in "female athletes" or when distinguishing between sexes.

Explanation: Biological sex ("female") and gender identity are distinct concepts, although the term "female" can also be applied socially.

Explanation: The evolution of sexual reproduction, particularly the emergence of males, is a central question when considering the evolutionary trajectory of females.

Explanation: Producing large amounts of pollen is identified as a cost associated with being male in plants.

Explanation: The "lock-and-key" mechanism posits that female genitalia evolved to ensure specific physical compatibility with male reproductive structures.

Explanation: Smaller, motile gametes (sperm) enhance fertilization efficiency by increasing their capacity to find and reach larger, less mobile female gametes (ova).

Explanation: Costs for males can include investing resources in traits for sexual display, such as elaborate plumage or antlers, to attract mates.

Explanation: Anisogamy is theorized to be advantageous as larger gametes enhance survival prospects, while smaller, motile gametes improve fertilization efficiency.

Explanation: The source indicates that anisogamy has evolved independently on multiple occasions throughout the history of life.

Explanation: The "lock-and-key" mechanism hypothesis proposes that female genitalia evolved based on specific physical compatibility requirements with male reproductive organs.