What two types of sperm result if nondisjunction of sex chromosomes occur during meiosis 1?

1. What happens if nondisjunction occurs during meiosis 1?
2. What is the result of nondisjunction during meiosis?
3. How does nondisjunction occur in meiosis 1 and 2?
4. What can result from nondisjunction?
5. Which of the following happens if nondisjunction occurs during meiosis 2?
6. Which describes the cells at the end of meiosis 1 when nondisjunction occurs during meiosis 2?
7. What are the types of nondisjunction?
8. What happens during meiosis to produce an aneuploid?
9. How does nondisjunction during meiosis I differ from nondisjunction in meiosis II?
10. What is the difference between meiosis 1 and meiosis 2?
11. Does Down syndrome occur in meiosis 1 or 2?
12. Which process would cause nondisjunction if it occurred during meiosis quizlet?
13. How can you tell if nondisjunction occurs in meiosis 1 or 2?
14. Which two processes contribute to genetic variety during meiosis?

What happens if nondisjunction occurs during meiosis 1?

Nondisjunction can occur during either meiosis I or II, with differing results (Figure 1). If homologous chromosomes fail to separate during meiosis I, the result is two gametes that lack that particular chromosome and two gametes with two copies of the chromosome.

What is the result of nondisjunction during meiosis?

Nondisjunction in meiosis can result in pregnancy loss or birth of a child with an extra chromosome in all cells, whereas nondisjunction in mitosis will result in mosaicism with two or more cell lines. Aneuploidy may also result from anaphase lag.

How does nondisjunction occur in meiosis 1 and 2?

Nondisjunction occurs when homologous chromosomes (meiosis I) or sister chromatids (meiosis II) fail to separate during meiosis. ... An individual with an error in chromosome number is described as aneuploid, a term that includes monosomy (loss of one chromosome) or trisomy (gain of an extraneous chromosome).

What can result from nondisjunction?

Nondisjunction: Failure of paired chromosomes to separate (to disjoin) during cell division, so that both chromosomes go to one daughter cell and none go to the other. Nondisjunction causes errors in chromosome number, such as trisomy 21 (Down syndrome) and monosomy X (Turner syndrome).

Which of the following happens if nondisjunction occurs during meiosis 2?

If nondisjunction occurs during anaphase II of meiosis II, it means that at least one pair of sister chromatids did not separate. In this scenario, two cells will have the normal haploid number of chromosomes. Additionally, one cell will have an extra chromosome (n + 1) and one will be missing a chromosome (n - 1).

Which describes the cells at the end of meiosis 1 when nondisjunction occurs during meiosis 2?

One cell with extra homologous chromosomes and one cell missing a homologous chromosome. Which describes the cells at the end of meiosis I when nondisjunction occurs in meiosis II? The homologous pairs are in separate cells. The cells are haploid.

What are the types of nondisjunction?

There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis. Nondisjunction results in daughter cells with abnormal chromosome numbers (aneuploidy).

What happens during meiosis to produce an aneuploid?

Aneuploidy is caused by nondisjunction, which occurs when pairs of homologous chromosomes or sister chromatids fail to separate during meiosis. The loss of a single chromosome from a diploid genome is called monosomy (2n-1), while the gain of one chromosome is called trisomy (2n+1).

How does nondisjunction during meiosis I differ from nondisjunction in meiosis II?

Nondisjunction can occur during meiosis I and meiosis II, resulting in abnormal chromosomes number of gametes. The key difference between nondisjunction in meiosis 1 and 2 is that during meiosis 1, homologous chromosomes fail to separate while in meiosis II sister chromatids fail to separate.

What is the difference between meiosis 1 and meiosis 2?

However, Meiosis I begins with one diploid parent cell and ends with two haploid daughter cells, halving the number of chromosomes in each cell. Meiosis II starts with two haploid parent cells and ends with four haploid daughter cells, maintaining the number of chromosomes in each cell.

Does Down syndrome occur in meiosis 1 or 2?

DS results from nondisjunction (NDJ) of chromosome 21 during either of the two stages of meiosis, meiosis I (MI) or meiosis II (MII), or after the first few divisions (mitosis) of the embryo.

Which process would cause nondisjunction if it occurred during meiosis quizlet?

Nondisjunction can occur during anaphase of meiosis I or meiosis II. If it happens during meiosis I, an entire bivalent migrates to one pole (Figure 8.22a). Following the completion of meiosis, the four resulting haploid cells produced from this event are abnormal.

How can you tell if nondisjunction occurs in meiosis 1 or 2?

Nondisjunction in meiosis I occurs when the tetrads fail to separate during anaphase I. At the end of meiosis I, there will be 2 haploid daughter cells, one with n+1 and the other with n-1.

Which two processes contribute to genetic variety during meiosis?

Genetic variation is increased by meiosis

Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote. Recombination or crossing over occurs during prophase I.