Reproductive cells also called sex cells. The main difference between male and female gametes is that male gametes are called sperm cells and are produced by the male reproductive organs whereas female gametes are called egg cells and are produced by the female reproductive organs. Both male and female gametes are produced by meiosis of the germ cells. Therefore, both male and female gametes are haploid. One male and one female gamete unite during the fertilization to form the diploid zygote.
In seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells. Female gametes of the seed-bearing plants are found inside the ovary. In animals, male and female gametes are produced in male and female gonads, respectively. The male gametes are the reproductive cells which unite with female reproductive cells during fertilization to produce a zygote. Male gametes are also called sperm cells.
They are produced by both plants and animals in a process called meiosis. The differentiation process of the sperms is called spermatogenesis. The two types of seed bearing plants are angiosperms and gymnosperms. Angiosperms are flowering plants.
The male reproductive organ of a flower is called stamens. The stamen is composed of an anther and a filament. In angiosperms, the male gametes can be found inside the pollen grains.
The pollen grains are produced inside the pollen sacs of the anthers. In non-flowering plants such as gymnosperms, male gametes are produced inside the pollen cones. The sperm cells that are produced by animals are called spermatozoa. Most animal sperms are flagellated except the sperms of nematode, crayfish, millipedes, and mites. In higher vertebrates, sperms are produced in the testes.
Head and tail are the two components of a matured sperm. The head of the human sperms are almond-shaped and mainly contain the nucleus. The nucleus comprises one set of chromosomes of the species.
The cap-like structure that covers the head of the sperm is called the acrosome. The acrosome contains enzymes to degrade the protective layers of the female gamete. Mitochondria can be found in the middle of the sperm.
The tail of the sperm consists of a flagellum , which is involved in the movement of the sperm. The spermatozoa are shown in figure 2.
MLA 8 P, Rachita. Name required. Email required. Please note: comment moderation is enabled and may delay your comment. There is no need to resubmit your comment. Notify me of followup comments via e-mail. Written by : rachita. User assumes all risk of use, damage, or injury.
You agree that we have no liability for any damages. Author Recent Posts. Latest posts by rachita see all. Difference between near sightedness and far sightedness - January 21, Difference between Diverticulosis and Diverticulitis - January 20, Difference between Prilosec and Nexium - January 19, Help us improve. Rate this post! How many people could pick the sex of a sea urchin pictured left or a clam simply by looking at it? In many animal species, males do not have anything remotely similar to an inseminating organ.
There are also many examples of animals where the males and females do not subscribe to what we perceive as traditional sex roles — such as some fish and bird species , in which only the male looks after the eggs. In the case of seahorses, the males actually physically carry and incubate the offspring. So, if not based on anatomical features, can sex be traced to the level of chromosomes? The XY sex-determination system is well-known because it occurs in humans, many vertebrates and some insects.
In this system males have two kinds of sex chromosomes XY , while females have two copies of the same sex chromosome XX. But in birds, and a number of reptiles and butterflies, the reverse patterns is the norm ZW for females, ZZ for males. Sexual chromosomes are also paramount in controlling hormones that unleash profound developmental changes that are in many cases easily identifiable. Without doubt, we all use a range of such hormone-induced indicators to determine who is a male and who is a female on a daily basis, at least when it comes to humans e.
Hence, at first glance, sex chromosomes may appear to be the way to go in defining sex. Look a bit deeper, though, and this approach is also far from watertight. In many reptiles, sex determination comes via the temperature experienced by the embryos. And then there are species in which individuals spend one part of their life as one sex and another part as the other.
Some even live their lives as males and females simultaneously so called hermaphrodites , such as the land snails pictured right that wreak damage to our back-garden vegetable crops each spring. So is there any character we can single out that would adequately define the sexes? Well, yes, there is. The answer relates to the size of cells that will fuse together to produce the next generation the sex cells or gametes. Following from this, by definition, the evolutionary origin of males and females lies in the transition from isogamy when the gametes in all individuals are all of equal size to anisogamy sexual reproduction involving sex cells of different sizes.
So the crucial point is not the terminology.
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