Reproductive System Flashcards
(138 cards)
Sexual reproduction in humans involves:
Meiosis
Fertilization
Prenatal Development
_____-Cell division producing four genetically unique haploid cells (called gametes= sperm in male or ova in female) from stem cells within the gonads that are diploid 2(n) = 46 (Containing two sets of chromosomes).
Gametes are haploid (n) = 23 having only one set of chromosomes
Meiosis
Meiosis
What are gametes?
sperm in male or ova in female
Meiosis
What do the diploid 2 (n) contain?
46 (Containing two sets of chromosomes).
Gametes are _____when having only one set of chromosomes?
Haploid (n) = 23 chromosomes
What is a zygote (2n)?
Fusion of sperm and egg
_____-Fusion of sperm and egg
Creates a zygote (2n), or fertilized egg that will develop into a new organism
Fertilization
_____-zygote grows as cells divide by mitosis:
Mitotic cell division produces two genetically identical cells.
Prenatal Development
Chromosomes:
Humans have _____pairs of chromosomes
23
Chromosomes:
Each somatic cell has two sets of chromosomes (one maternal, one paternal) and is said to be _____ so the chromosome number is 2n.
diploid
Chromosomes:
_____-matching pairs of chromosomes that carry equivalent genes.
Homologous chromosomes
Chromosomes:
There are alternative forms of each gene which are called _____
alleles
Chromosomes:
Gametes only have 23 chromosomes and are said to be_____
haploid (n)
Chromosomes;
One pair of chromosomes, called the _______, determines the sex of the individual (XX in females, XY in males).
sex chromosomes
_____-is a type of cell division that produces gametes (sperm and ova) from stem cells in the reproductive tissue
Meiosis
Meiosis:
______-in preparation for fusing with another gamete
Reduces the original number of chromosomes in half
Meiosis:
____-(scrambling) of parents’ genomes to create a unique set of chromosomes in each gamete
Recombination
Stage of meiosis?
overview Intrephase Meiosis I -Prophase I -Metaphase I -Anaphase I -Telophase I and cytokinesis
Meiosis II Prophase II Metaphase II Anaphase II Telophase II and cytokinesis
What stages of meiosis is this?
_____-In meiosis there is two rounds of division which results in 4 haploid cells:
1st round separates duplicated homologous chromosomes
2nd round separates sister chromatids
Overview
What stages of meiosis is this? \_\_\_\_\_\_\_\_- Occurs prior to Prophase I of meiosis G1 phase S-phase homologous chromosomes replicate into sisters G2 phase – checkpoint
Interphase
What stages of meiosis is this?
____-first division
Meiosis I
What occurs in Meiosis I?
______-
Duplicated homologous chromosomes pair up (tetrads)
Crossing over occurs: homologous chromosome exchange equivalent segments
Prophase I
What occurs in Meiosis I?
____-
Homologous chromosomes line up in pairs along the central plane in tetrads
Independent assortment: which side each chromosome lines up on is independently of the other pairs
Metaphase I
What occurs in Meiosis I?
_____-
Homologous chromosomes are separated and move to opposite poles
Anaphase I