Male (♂) refers to the sex of an organism, or part of an organism, which produces small mobile gametes A gamete is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum (or egg)—and a, called spermatozoa. Each spermatozoon can fuse with a larger female Female is the sex of an organism, or a part of an organism, which produces non-mobile ova (egg cells) gamete or ovum An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization. In lower plants and algae, the ovum is also often called oosphere, in the process of fertilization Fertilization , is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo. Depending on the animal species, the process can occur within the body of the female in internal fertilisation, or outside in the case of external fertilisation. A male cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually.
Not all species share a common sex-determination system. In humans Humans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving members of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving. This mental capability, combined with an erect body carriage that frees the and most animals, sex is determined genetically Genetics , a discipline of biology, is the science of heredity and variation in living organisms. The fact that living things inherit traits from their parents has been used since prehistoric times to improve crop plants and animals through selective breeding. However, the modern science of genetics, which seeks to understand the process of but in other species it can be determined due to social, environmental, or other factors.
The existence of two sexes seems to have been selected independently across different evolutionary lineages An evolutionary lineage is a sequence of species, that form a line of descent, each new species the direct result of speciation from an immediate ancestral species. Lineages are subsets of the evolutionary tree of life. Lineages are often determined by the techniques of molecular systematics (see Convergent Evolution The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, birds and bats do, and are capable of powered flight. The wings are similar in construction, due to the physical constraints imposed upon wing shape. Similarity can also be explained by shared ancestry, as evolution can only). The repeated pattern is sexual reproduction in isogamous Isogamy refers to a form of sexual reproduction involving gametes of similar morphology, differing only in allele expression in one or more mating-type regions. Since both gametes look alike, they cannot be classified as "male" or "female." Instead, organisms undergoing isogamy are said to have different mating types, most species with two or more mating types Mating types occur in eukaryotes that undergo sexual reproduction via isogamy. Since the gametes of different mating types look alike, they are often referred to by numbers, letters, or simply "+" and "-" instead of "male" and "female." Mating can only take place between different mating types with gametes of identical form and behavior (but different at the molecular level) to anisogamous There are several types of anisogamy. Both gametes may be flagellated and thus motile. Alternatively, neither of the gametes may be flagellated. This situation occurs for example in some algae and plants. In the red alga Polysiphonia, large non-motile egg cells are fertilized by small, non-motile spermatia. In flowering plants, the gametes are non- species with gametes A gamete is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum (or egg)—and a of male and female Female is the sex of an organism, or a part of an organism, which produces non-mobile ova (egg cells) types to oogamous Oogamy is the familiar form of sexual reproduction. It is a form of anisogamy in which the female gamete (e.g. egg cell) is significantly larger than the male gamete and is non-motile. The male gametes are typically highly motile spermatozoa competing for the fertilization of the immotile egg species in which the female gamete is very much larger than the male and has no ability to move. There is a good argument that this pattern was driven by the physical constraints on the mechanisms by which two gametes get together as required for sexual reproduction. [1]
Accordingly, sex is defined operationally An operational definition is a demonstration of a process – such as a variable, term, or object – in terms of the specific process or set of validation tests used to determine its presence and quantity. The term was coined by Percy Williams Bridgman . Properties described in this manner must be sufficiently accessible, so that persons other across species by the type of gametes produced (ie: spermatozoa vs. ova) and differences between males and females in one lineage are not always predictive of differences in another.
Male/Female Female is the sex of an organism, or a part of an organism, which produces non-mobile ova (egg cells) dimorphism between organisms or reproductive organs of different sexes is not limited to animals; male gametes are produced by chytrids Chytridiomycota or chytrids (sg. pronounced /ˈkɪtrɪd/, KIT-rid) is a division of the Fungi kingdom. The name is derived from the Greek chytridion, meaning "little pot", describing the structure containing unreleased spores. In older classifications, chytrids (except the recently established order Spizellomycetales) were placed in the, diatoms Diatoms are a major group of eukaryotic algae, and are one of the most common types of phytoplankton. Most diatoms are unicellular, although they can exist as colonies in the shape of filaments or ribbons , fans (e.g. Meridion), zigzags (e.g. Tabellaria), or stellate colonies (e.g. Asterionella). Diatoms are producers within the food chain. A and land plants Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004,, among others. In land plants, female and male designate not only the female and male gamete-producing organisms and structures but also the structures of the sporophytes All land plants, and some algae, have life cycles in which a haploid gametophyte generation alternates with a diploid sporophyte, the generation of a plant or alga that has a double set of chromosomes. A multicellular sporophyte generation or phase is present in the life cycle of all land plants and in some green algae. For common flowering plants that give rise to male and female plants.
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Wall Street Journal
For example, 60% of women respondents reported that their first job was at an entry level position, as opposed to 46% of male respondents. ...
Female MBAs earn less: study Montreal Gazette
Report finds pay and promotion disparities for women executives Kansas City Star
Playing field uneven for female MBA grads Globe and Mail
Investment Executive - Bizjournals.com (blog) - Toronto Star
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