similar gametes (sex cells)
Source: Noland, George B. 1983. General Biology, 11th Edition. St. Louis, MO. C. V. Mosby ...
Gametes are specialised haploid cells that are used to combine and when they do they combine to form a new diploid cell. That process of combination is called fertilization.
gametes Haploid reproductive cells (ovum and sperm). PICTURE
gametophyte The haploid stage of a plant exhibiting alternation of generations, generates gametes by the process of mitosis.
gametes /GAM-eets/ n. Haploid reproductive cells. Two gametes, one of each sex, fuse during fertilization to produce a zygote during sexual reproduction. A female reproductive cell is an ovum (or egg) and a male reproductive cell is a spermatozoon.
Gametes from human ES cells?
Working with mice, several laboratories report that they have been able to coax ES cells to differentiate into cells with some of the properties of gametes, including ...
Haploid egg or sperm cells that unite during sexual reproduction to produce a diploid zygote.
Covered in BIOL1020 Lab 6 Mitosis & Meiosis ...
~ sex cells of parent organisms; usually haploid cells.
gastrin a hormone produced by digestive glands to influence digestive processes.
gene the functional segment of chromosomes.
~ - Cells with the haploid number of chromosomes. ~ are created out of germ cells. The sperm and eggs involved in sexual reproduction are ~.
11. Are ~ always made by meiosis?
In the plant life cycle (diplobiontic life cycle) and in the haplontic haplobiontic life cycle ~ are made by mitosis and not by meiosis. Obviously in some stage of these sexual life cycles meiosis must occur.
~ are haploid cells; that is, they contain one complete set of chromosomes (the actual number varies from species to species). When two ~ fuse (in animals typically involving a sperm and an egg), they form a zygote-a cell that has two complete sets of chromosomes and therefore is diploid.
~ Mature haploid cells (sperm and ova) that fuse to form a zygote.
gametic meiosis. Meiosis that occurs during formation of the ~, as in humans and other metazoa.
gametocyst Cyst produced by some apicomplexan parasites. Sexual reproduction and spore formation occurs within this cyst.
~ arise from choanocytes or amoebocytes.
The eggs are retained, but sperm are carried out the osculum by the water current.
Sperm are drawn into neighboring individuals and fertilize eggs in the mesohyl.
The zygotes develop into flagellated, swimming larvae that disperse from the parent.
~ that do not undergo syngamy shortly after they are formed or activated, die.
When ~ are different sizes, the larger are called eggs and the smaller sperm.
Organisms that produce sperm are male, those that produce eggs are female.
2) ~: Sperm and eggs are the cornerstones of sexual reproduction. They are called ~, and animals spend a lot of time and energy making them. They need to be ready for the moment when they can combine ~ with their dream partner.
The ~ of a plant of genotype SsYy should have the genotypes:
A. Ss and Yy
B. SY and sy ...
Both ~ the same (isogamy).
Like other species of Cladophora, C. callicoma has flagellated ~ which are identical in appearance and ability to move.
~ of two distinct sizes (anisogamy).
Fusion of ~ formed by different individuals; as opposed to self-fertilization.
The reciprocal exchange of genetic material between nonsister chromatids during synapsis of meiosis I.
Heterogamy ~ differ in size and structure and in their roles in reproduction.
Heterotrophic nutrition form of feeding in which the organism consumes complex organic material.
Heterozygote a condition in which the alleles of a particular gene are different.
noun, plural: ~
(1) A reproductive cell or sex cell that contains the haploid set of chromosomes, e.g. spermatozoon or sperm cell (male reproductive cell) and egg cell or ovum (female reproductive cell).
The possible ~ from the homozygous parent seal are on the left in front of the rows, & the possible ~ from the heterozygous parent are above the columns. We fill in the boxes by copying "one letter from the left, one letter from the top".
Telophase II shows the DNA completely pulled to the sides and the cell membrane begins to pinch. When it's all over, you are left with four haploid cells that are called ~. The eventual purpose of the ~ will be to find other ~ with which they can combine.
somatic cell: Any cell in the body except ~ and their precursors. [DOE] Are the precursors stem cells?
All body cells, except the reproductive cells. NHGRI See also somatic cells Molecular Medicine ...
In instances of sexual reproduction, the cellular process of meiosis is first necessary so that haploid daughter cells, or ~, can be produced. Two haploid cells then fuse to form a diploid zygote, which develops into a new organism as its cells divide and multiply.
Genetic linkage is thought to arise to accommodate genes that function best in each other's company, i.e., to provide a necessary cooperative effect that enhances survival. Genetic linkage reflects a lack of meiotic crossovers between two genes (see exercises on ~ under Linkage and ...
Mitosis produces 2 new cells with the full set of 46 chromosomes (diploid) while meiosis produces cells with half the number of chromosomes (23 chromosomes in the haploid set for humans). The cells produced through meiosis are called ~ and are are used for reproduction.
The resulting 2n ~, if fertilized by normal sperm, create 3n zygotes (triploid).
Organisms with an odd number of chromosome sets cannot produce viable ~ (Example: seedless fruits).
The reduction division process by which haploid ~ and spores are formed, consisting of a single duplication of the genetic material followed by two mitotic divisions. Messenger RNA (mRNA).
Artificial insemination -- the placement of sperm into a female reproductive tract or the mixing of male and female ~ by other than natural means. Autosome -- a nuclear chromosome other than the X- and Y-chromosomes.
~ are haploid (one copy of each autosome) (figure 1). Normal hepatocytes are tetraploid.
Most animal cells except the ~ have a diploid set of chromosomes. The diploid human genome has 46 chromosomes.
See also: haploid (ORNL)
Directed evolution ...
The purpose of meiosis is to produce haploid (1n) ~. Another purpose is to recombine genes from the parents of the individual in whom meiosis is occurring. Both the reduction of the chromosome number from 2n to 1n and the recombination of genes is accomplished in an amazingly simple way.
Meiotic drivers are genes that subvert the normal rules of inheritance to ensure that they are present in more than their fair share of ~ in the next generation .
(B) Heatmap showing the methylation in ~ and blastocysts for all the CGIs methylated (50%) in E8.5 embryos. Approximately half of the CGIs inherit partial methylation from the oocyte. (C) Percentage of CGIs that gain 50% methylation in E8.
This leads the production of ~ that either have a chromosome too many or too few. ~ with a missing chromosome usually die quite fast however ~ with an extra chromosome can survive.
In a finite population (as all biological populations are) the ~ contributing to the next generation are a sample of the alleles in the gene pool.
All of the alleles available among the reproductive members of a population from which ~ can be drawn.
The term coined by Bateson and Saunders (1902) for characters which are alternative to one another in Mendelian inheritance (Gk. Allelon, one another; morphe, form).
The mass of DNA in somatic cells is constant, while ~ have half this mass.
DNA is associated with the chromosomes (but so is protein).
Mutagens that affect DNA molecules cause increased phenotypic mutation.
This means that when somatic cells are produced from two ~, one allele comes from the mother, one from the father. These alleles may be the same (true-breeding organisms, e.g. ww and rr in Fig. 3), or different (hybrids, e.g. wr in Fig. 3).
Meiosis results in four rather than two daughter cells (~), each with a haploid set of each chromosome pair. In meiosis I the prophase is more complex than that of mitosis. Five different stages can be differentiated: leptotene, zygotene, pachytene, diplotene and diakinesis.
Conclusion : in most cases, the division results in spores or ~. The cell has given rise to four daughter cells, each with a different set of chromosomes.
Two successive nuclear divisions (with corresponding cell divisions) that produce haploid ~ (in animals) or haploid sexual spores (in plants and fungi) having one-half of the genetic material of the original cell.
Any precursor cell that can give rise to ~. See also somatic cell.
Lineage of germ cells, which give rise to ~ and thus participate in formation of the next generation of organisms; also the genetic material transmitted from one generation to the next through the ~.
female (being the sex (of plant or animal) that produces fertilizable ~ (ova) from which offspring develop)
male (being the sex (of plant or animal) that produces ~ (spermatozoa) that perform the fertilizing function in generation)
in vivo (within a living organism) ...
During the production of sex cells (~) in animals
In spore formation which precedes gamete production in plants
Haploid ~ (sperm ovum) - sexual reproduction
DNA in a cell replicates only once, but cell divides twice ...
Sexual reproduction - Type of reproduction in which two ~ (usually, but not necessarily, contributed by two different parents) fuse to form a zygote.
Spindle - Structure consisting mainly of microtubules that provides the framework for chromosome movement during cell division.
isogamous - having haploid ~ that are similar in size, structure and motility.
isometric growth - growth that occurs at the same rate for all parts of an organism so that its shape is consistent throughout development. Contrast with allometric growth.
Fertilization: the union of male and female ~ to form a zygote, initiating biological reproduction.
Gamete: a mature sexual reproductive cell, as a sperm or egg, that unites with another cell during fertilization to form a new organism.
Epidemic spawning. Simultaneous shedding of ~ by a large number of individuals
Epipelagic zone. The 0- to 150-m-depth zone, seaward of the shelf-slope break
Epiphyte. Microalgal organism living on a surface (e.g., on a seaweed frond) ...
The process of nuclear division associated with the formation of ~ or of haploid cells from a diploid.
A partially diploid bacterium, carrying both its own chromosome and a chromosome fragment introduced by conjugation, transformation or transduction.
Any cell in the body except ~ and their precursors.
See also: gamete
Somatic cell gene therapy
Incorporating new genetic material into cells for therapeutic purposes. The new genetic material cannot be passed to offspring.
See also: gene therapy ...
Gametophyte in plants and algae‚ the 1n generation which produces ~ (eggs and sperm)
(gamet = marriage‚ reproduction; phyto = plant)
Gastric Juice collective name for the secretions of the stomach lining‚ containing HCl‚ pepsin‚ and other chemicals
(gastro = stomach) ...
Self-fertilization in a hermaphroditic species where the two ~ fused in fertilization come from the same individual.
A locus that is located on an autosome (i.e., not on a sex chromosome).
Haploid. A cell or organism containing the set of chromosomes normally found in ~.
Haplotype. A number of functionally related loci that are closely linked genetically. Alternative sates of such complexes are termed haplotypes.
- Mode of asexual production in which there is no fusion of ~ but the structure involved are commonly concerned in sexual reproduction.
So there has to be a way to take those paired chromosomes and break them apart in order to make ~; sperm and eggs. That's what meiosis is all about.
Gene flow: The exchange of genetic traits between populations by movement of individuals, ~, or spores. It involves the spread of new variants among different populations through dispersal.
Fertilization: Fusion of female and male haploid ~ to form a diploid zygote from which a new individual develops.
Fetus: Final development stage before birth (following embryo).
Disjunction The normal process by which the two homologs of each chromosome in a meiotic cell separate and move to different ~ (see Chapter 5).
Distal A relative term meaning closer to the telomere; the opposite of proximal.
Diploid: A full set of genetic material, consisting of paired chromosomes one chromosome from each parental set. Most animal cells except the ~ have a diploid set of chromosomes. The diploid human genome has 46 chromosomes.
gametogenesis [Gr. gamos - a marriage; Gr. genesis - origin, descent]. The formation of male and female sex cells or ~ (spermatozoa and ova, respectively) from germ cells.
haploid -- Having a single set of chromosomes in the nucleus of each cell. Mosses, and many protists and fungi, are haploid, as are some insects, bryophytes, and the ~ of all organisms. Contrast with diploid.
Gamete (1N): NUCLEAR ENVELOPES form and chromosomes disperse as CHROMATIN. Meiosis has produced 4 DAUGHTER CELLS, each with 1N chromosomes and 1N DNA. Later, in fertilization, male and female 1N ~ will fuse to form a 2N ZYGOTE.
Some Keywords: ...
Over many millions of years mutations and random genetic drift erode the Y chromosome, turning it into a genetic junkyard. In contrast, genes on the X are present in both males and females; X chromosomes, like autosomes, recombine in production of female ~.
MeiosisThe type of cell division that occurs in sex cells by which ~ having the haploid number of chromosomes are produced from diploid cells. Messenger RNA (mRNA)Type of RNA polymerase using DNA as a template.
See also: What is the meaning of Gamete, Organ, Cells, Chromosome, Cell?