What is gametogenesis in animal development?
Gametogenesis is the production of gametes from haploid precursor cells. In animals and higher plants, two morphologically distinct types of gametes are produced (male and female) via distinct differentiation programs. Animals produce a tissue that is dedicated to forming gametes, called the germ line.
What is the importance of the developmental stages of gametogenesis in animal development?
Gametogenesis is a significant part of mammal reproduction through which the germ cell lineage undergoes a series of complex developmental processes and forms fully matured gametes, the spermatozoa and the oocytes. A number of conditions, including infertility, result from the abnormal circumstances of gametogenesis.
What comes first fertilization or gametogenesis?
The cells need to develop before they become mature gametes capable of fertilization. The development of diploid cells into gametes is called gametogenesis. A gamete produced by a female is called an egg, and the process that produces a mature egg is called oogenesis.
What are the steps of fertilization and embryo development in animals?
The process of fertilization is tightly controlled to ensure that only one sperm fuses with one egg. After fertilization, the zygote undergoes cleavage to form the blastula. The blastula, which in some species is a hollow ball of cells, undergoes a process called gastrulation, in which the three germ layers form.
What are the similarities and differences between gametogenesis in animals and plants?
The major difference between gametogenesis in animals and plants is that in animals it includes the transformation of the cells from diploid cells to haploid cells and the formation of haploid gametes; and in plants gametogenesis is the formation of the gametes from haploid cells.
What are the six stages of animal development?
Animal will go through six basic stages of development. They are fertilization of egg (ovum) and sperm, cleavage, gastrulation, neurulation, organogenesis and metamorphosis (refer to Figure 1 in Appendix 1).
Which processes in animals result in growth and development?
The main processes involved in the embryonic development of animals are: tissue patterning (via regional specification and patterned cell differentiation); tissue growth; and tissue morphogenesis.
What are the stages of gametogenesis?
Gametogenesis is divided into four phases:
- Extra-gonadal origin of primordial germ cells.
- Proliferation of germ cells by mitosis.
- Meiosis.
- Structural and functional maturation of the ova and spermatozoa.
What is the correct order of steps in the cell cycle?
The cell cycle is a four-stage process in which the cell increases in size (gap 1, or G1, stage), copies its DNA (synthesis, or S, stage), prepares to divide (gap 2, or G2, stage), and divides (mitosis, or M, stage). The stages G1, S, and G2 make up interphase, which accounts for the span between cell divisions.
What are the stages of embryo development?
This union marks the beginning of the prenatal period, which in humans encompasses three distinct stages: (1) the pre-embryonic stage, the first two weeks of development, which is a period of cell division and initial differentiation (cell maturation), (2) the embryonic period, or period of organogenesis, which lasts …
What is animal fertilization?
Fertilization in animals is a biological process that involves a sperm (male gamete) merging with an egg (female gamete or ovum) [Fig. 1] and leading to the development of an embryo. Gametes (germ cells or sex cells) are haploid because their nuclei contain only one set of chromosomes.