compare and contrast sexual and asexual reproduction?
463700
Contrast:\n- Asexual reproduction is done with only one individual or cell in the process (called mitosis) and usually involves splitting or grafting of the original organism.\n- Sexual reproduction occurs when one cell fertilizes another (sperm and egg are the most common terms for it) and it usually results in a more stable gene pool because more chromosome combinations are possible.\n\nCompare:\n- They both involve reproduction at the cellular level.\n- They both involve some manner of genetics (either splitting or joining)\n- They both produce offspring.
576764
Asexual reproduction\n\n\nAsexual reproduction is the biological process by which an organism creates a genetically-similar or identical copy of itself without a contribution of genetic material from another individual. Bacteria divide asexually via binary fission; viruses take control of host cells to produce more viruses; Hydras (invertebrates of the order Hydroidea) and yeasts are able to reproduce by budding. These organisms do not have different sexes, and they are capable of "splitting" themselves into two or more individuals. Some 'asexual' species, like hydra and jellyfish, may also reproduce sexually. For instance, most plants are capable of vegetative reproduction—reproduction without seeds or spores—but can as well reproduce sexually. Likewise, bacteria may exchange genetic information by conjugation. Other ways of asexual reproduction include fragmentation and spore formation that involves only mitosis.\n\n\nSexual reproduction\n\nSexual reproduction is a biological process by which organisms create descendants that have a combination of genetic material contributed from two (usually) different members of the species. Each of two parent organisms contributes half of the offspring's genetic makeup by creating haploid gametes. Most organisms form two different types of gametes. In these anisogamous species, the two sexes are referred to as male (producing sperm or microspores) and female (producing ova or megaspores). In isogamous species the gametes are similar or identical in form, but may have separable properties and then may be given other different names. For example, in the green alga, Chlamydomonas reinhardtii, there are so-called "plus" and "minus" gametes. A few types of organisms, such as ciliates, have more than two kinds of gametes.\n\nHumans, most animals, and plants reproduce sexually. Sexually-reproducing organisms have two sets of genes for every trait (called alleles). Offspring inherit one allele for each trait from each parent, thereby ensuring that offspring have a combination of the parents' genes. Having two copies of every gene, only one of which is expressed, allows deleterious alleles to be masked, an advantage believed to have led to the evolutionary development of diploidy (Otto and Goldstein).
1003518
First question. If you mean sexual interciurse then of course, IVF (AI) etc\nBut as this is biology then ill assume you mean syngamy between gamets. \nIn which case the option is cloning which is not established as viable in humans yet (Korean research is under fraud investigation so its validity unclear at present) but is not permitted in most countries anyway.\n\nAs to the second question:- NO\nAsides one alleged and unlikely case (the virgin birth of mary yielding jesus christ which if it was true (unlikely) was a dead end as it was a male), parthenogensis (asexual reproduction) has never been reported in humans. Morever it is very unlikely to be viable or to occur due to imprinting etc.
416340
I would have to answer that you're asking the wrong question!  \n\nThe explanation of how a plant or animal can develop asexual reproduction isn't going to help you better understand incremental changes via evolution; what you really need to understand is how a plant or animal can develop sexual reproduction. \n\nLooking at the first, microbiological life, asexual reproduction - i.e. cell division or 'budding' -  was the first and most essential form of reproduction. It took century upon century for more complex life to develop and specialize; and, for the mechanisms of sexual reproduction to develop and become established. \n\nThe change from asexual to sexual reproduction would indeed have been  massive, but it doesn't follow that it had to be sudden. When scientists look at species and evolution, they will generally say that one species was more successful at adapting to their environment than another. \n\nIt seems that the ancestors of many plants and animals developed sexual reproduction mechanisms, and they were more successful in competing with other animals for food/territory, over an extended period of time. The less successful ones died out long ago.\n\nSo - it may not be totally accurate to say, "reproduction either works or it doesn't." A better statement would be, "evolutionarily speaking, changes in species over time may cause one method of reproduction to become less successful than another."  \n\nHaving said that: there are other scientists who agree that evolution isn't always slow and gradual; they argue that sometimes evolution happens occasionally in a sudden and dramatic way, when one species splits to become new species - generally the new species are created when one population becomes separated by geographic boundaries. \n\nI'd strongly suggest reading the Wikipedia article (linked below) on Stephen Jay Gould for an evolutionary point of view which counters the slow evolution methodologies advocated by Dawkins; as well as the articple on evolution itself - which looks at the development of the understanding of evolutionary principles and their historical context.
575385
In the logic of evolution theory, heterosexual intercourse is likely to be an innate drive, otherwise our species would be bound to disappear. This for the physical part of it.\nNow in the domain of mental perceptions of sexuality, there's a greater part of acquired things rahter than innate ones.\nBut your question actually contains a paradox, as you state about the internet growth (more generally the spreading of information because TV, advertisement, magazines also contribute to make us more, err..., kinky). We are actually being TAUGHT to become more kinky, striving for various alternatives to the classical hetero one to one.
158195
Yeast can reproduce both sexually and asexually.  It can bud off to creat offspring genetically identical to the parent.  However, when resources are scarce, yeast cells can form ascospores and sexually reproduce.  Sexual reproduction may create offspring more suitable to the environment and better able to utilize scarce resources, so it is utilized in times of hardship.\n\nHope this helps, please don't forget to come back and mark a best answer!\n\nMore information can be found here:\nhttp://en.wikipedia.org/wiki/Yeast
560072
The origin of males and females as we know them is an evolutionary enigma.  Asexual reproduction produces a much higher output, requires no gender, and only one individual.  The most widely-accepted reason for sex is that it provides a larger amount of genetic variation.  Instead of the genetic material of one parent organism, sex utilizes the genetic material of TWO organism.  Greater genetic variation insures that the species as a whole will have a greater chance of adapting to new environmental pressures, such as disease.  Thus, sexual reproduction evolved and gender was born.  Naturally, if two members of different genders are required to produce more of the same species, it is essential that these genders are attracted to one another.  If you have a type of animal in which males and females have no sexual interest in each other, the species is likely to go extinct once those initial animals die, due to a lack of new generations.  Bottom line: Human individuals who are attracted to the opposite sex are more likely to produce offspring than those individuals who are not, and these offspring will tend to inherit the parents' same attraction to the opposite sex.  Years of natural selection on species that reproduce sexually spawns a species characterized by the majority of any given gender being attracted to the opposite sex.
176612
Some plants can reproduce asexually using their stems, roots or by producing bulbs. These plants can also have flowers and reproduce sexually.
11918
This is probably the strangest question I have ever seen.  I suppose there are only two sexes because there is only one reason for there to be more than one sex:  reproduction.  Some organisms reproduce asexually, but their offspring are exact clones.  In order to create an entirely new organism, we need to have at two different sets of genes to combine.  Since we reproduce by sperm (male) and egg (female), how could there possibly be another sex capable of reproduction?
541267
survive and reproduce
244365
zero!  asexual reproduction hasn't occurred in the human species yet.
401226
The whiptail lizard has asexual reproduction. Check out this web site:\n\nhttp://www.pbs.org/wgbh/evolution/library/01/5/l_015_01.html
152309
yes you are an asexual person but not in all meanings of the word, you have sex organs so you are not completely asexual. It's not common at all most people are sexual in some way or form whether it be hetero homo or bi. kind of cool though, you have to be a very confident person not having to worry about how other see you.
607312
I am not sure what you mean by uni-sex in biology....\n\nIn biology, sexual reproduction is not said to have been started with only females per se! Uni sexual is not the same as hermaphroditic either. Monoecious and dieocious are the usual terms. Monoecious means hermaphrodite and dioecious means separate sexes. But reproduction can be either sexual or asexual (and sometimes some organisms do both, like, mosses, liverworts, ferns with alternation of generations.) \n\nThere are a few species of animals who have only females, though....at least 22 species of parthenogenic lizards identified last I checked! They lay eggs, mate like "lesbian lizards" without sperm and have babies. Wild!\n\nHowever, a "male" is usually described in biology as any organism that makes "sperm" gametes, so in that case, hermaphroditic organisms like most flowering plants (sperm is in pollen) have males as PART of the often hermaphroditic flower known as the stamen.  (some flowers are dioecious) So males are found in plants or animals.  In fact the anther is the pollen producing part of the stamen and is sorta comparable to the testes of the animal. In fungus there are opposite strains of hyphae that reproduce "sexually" but not with gametes and they are described as + and - branches, which some claim are m-f, but it is still considered sexual reproduction, whereby genetic information is exchanged and a genetically DIFFERENT offspring is produced. Asexual produces gentically identical offspring-clones. Bacteria usually reproduce asexually, but sexual conjugation can occur (sexual) in bacilli. Paramecium are the most famous for their sexual reproduction-conjugation too. In the cases of fungi, bacteria, paramecia, however, the gender is not considered even though it is considered SEXUAL. So what biologists consider as very "primative" organism are capable of sexual reproduction.
266130
The advantage is seen in the fishes who could slightly breathe through their skin.  When the pond dries up millions of times over hundreds of millions of years the descendants with better breathing could eventually stay ashore and ponder these questions.  The advantage of asexual reproduction is that you don't have to be cute.
480132
Basically, plants reproduce like most other organisms... sexually.  The main difference is that their young (seeds-to-be; ovules?) grow either inside a receptacle, or fruit, (angiosperms) or without a receptacle (gymnosperms).
276439
Sexual reproduction speeds the evolutionary process in that it creates larger variance in genetic material between individuals.