Sexual Reproduction And Meosis Flashcards
(20 cards)
What is sexual reproduction?
A process where genetic information from two organisms (a father and a mother) is combined to produce genetically different offspring.
What are gametes?
Reproductive cells produced by the father and mother, specifically sperm and egg cells in humans.
What is the diploid number of chromosomes in human cells?
46 chromosomes.
What is the haploid number of chromosomes in human gametes?
23 chromosomes.
What occurs at fertilization?
A male gamete fuses with a female gamete to produce a fertilized egg, known as a zygote.
What is a zygote?
A fertilized egg that has the full set of chromosomes, making it diploid.
What process does the zygote undergo after fertilization?
Cell division by mitosis to develop into an embryo.
How does the embryo inherit characteristics?
By receiving a mixture of chromosomes (and therefore genes) from both parents.
Where are male gametes found in flowering plants?
In the pollen.
Where are female gametes found in flowering plants?
In the ovaries at the bottom of the stigma.
What is meiosis?
A type of cell division that produces gametes and creates genetic variation.
Where does meiosis occur in humans?
In the reproductive organs (ovaries and testes).
What happens to the DNA before meiosis begins?
The cell duplicates its DNA to ensure enough for each new cell and one arm of each x shaped chromosome is an exact copy of the other arm
During the first division of meiosis, what happens to the chromosomes?
They line up in pairs in the center of the cell and are then pulled apart.
What is the result of the first division in meiosis?
Each new cell has one copy of each chromosome, mixing paternal and maternal chromosomes.
What is the significance of mixing genes during meiosis?
It creates genetic variation in the offspring.
What occurs during the second division of meiosis?
Chromosomes line up again and chromatids are pulled apart, resulting in daughter cells.
How many haploid daughter cells are produced at the end of meiosis?
Four haploid daughter cells, which are the gametes.
Fill in the blank: Gametes only have a _______ set of chromosomes.
single
True or False: In humans, meiosis occurs in all body cells.
False
