The length in the image above it appears

The ureter’s goes either side of the bladder and both should be the same length in the image above it appears as if both the ureters link and join to each other this is not the case (Clemente, 2011). Also, the ureter lies behind the ovary not in front as the picture shows (Clemente, 2011).

Oogenesis is the method of creating the female gametes, the Ovum, from the primordial germ cells (Browder, 1985). Most of the stages in oogenesis, up to the point of creating primary oocytes, happen pre-natally. Females are born with all the Primary Oocytes that they will ever have as primary oocytes don’t split further (Browder, 1985).No polar bodies are formed in spermatogenesis unlike oogenesis (Browder, 1985).

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a) Name of first stage: Multiplication Phase

Notes on key features:

The primordial germinal cells split over and over again to frame the oogonia (Browder, 1985). The oogonia duplicate by the mitotic divisions and create the primary oocytes which go through the development stage (Browder, 1985).

b) Name of second stage: Growth Phase:

Notes on key features:

The growth stage of the oogenesis is relatively longer than the growth stage of the spermatogenesis (Browder, 1985). In the development stage, the span of the primary oocyte increases dramatically (Browder, 1985). The cytoplasm of the oocyte develops rich in RNA, DNA, ATP and enzymes (Browder, 1985). In the growth stage, dramatic changes additionally happen in the nucleus of the primary oocyte (Browder, 1985). The nucleus gets big because of the expanded measure of the nucleoplasm and is called germinal vesicle (Browder, 1985). The chromosomes change their shape and end up noticeably mammoth light brush chromosomes which are specifically related with expanded transcription of messenger RNA atoms and protein synthesis in the cytoplasm (Browder, 1985). At the point when the development of the cytoplasm and nucleus of the primary oocyte is finished, it is then ready to progress onto the maturation phase (Browder, 1985).

c) Name of third stage: Maturation Phase – Meiosis I

Notes on key features:

The maturation stage is assisted by the maturation or meiotic division (Browder, 1985). The maturation division of the primary oocyte varies dramatically from the maturation division of the spermatocyte (Browder, 1985). After this the meiotic division of the nucleus and the cytoplasm of the oocyte, divides unevenly to shape a single big haploid egg and three little haploid polar bodies or polocytes near the end (Browder, 1985). If equal division was to happen to the primary oocyte the stored food volume would result in being given to the four daughter cells, this may affect the development of the embryo by being inadequate (Browder, 1985). As a result, these unequal divisions grant one out of the four daughter cells to accommodate the majority of the cytoplasm, whilst reserving food which is adequate for the developing embryo (Browder, 1985). The homologous chromosomes of the primary oocyte nucleus travel through the pairing or synapsis, duplication, chiasma development and crossing over, this occurs within the first maturation division or first meiosis I (Browder, 1985). Next due to contraction of the chromonemal fibres the nuclear membrane splits and the bivalent chromosomes travel in the direction of the opposite poles (Browder, 1985). The endoplasmic reticulum forms a new nuclear envelope around the daughter chromosome (Browder, 1985). Once karyokinesis has done its job the unequal cytokinesis takes place, resulting in a small haploid polar body or polocyte, along with a big haploid, secondary oocyte or ootid are produced (Browder, 1985).
Meiosis II is the Second meiotic division (Browder, 1985). Travelling through this meiosis II phase is the haploid secondary oocyte together with the first polocyte (Browder, 1985). As a result of the Meiosis II, the secondary oocyte forms a mature egg and a second polocyte (Browder, 1985). By the meiosis II stage the first polocyte additionally divides into two secondary polocytes (Browder, 1985). These polocyte then overflow out of the egg and deteriorate, meanwhile the haploid egg cell is then ready got the fertilisation (Browder, 1985).

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