Biology MegaQuiz 1/22/24 Flashcards
Chromosomes which carry the same type of genes; each pair has one chromosome from each parent
Homologous
All chromosomes are in homologous pairs
Diploid
No chromosomes are in homologous pairs
Haploid
How many chromosomes do human cells have in the diploid form
46
Reproduction with only one parent; offspring are clones of parent
Asexual
Reproduction with one or two parents; offspring are genetically unique from parent(s)
Sexual
Is Meiosis a linear or cyclical process
Linear process
T/F
A cell must exit the cell cycle to begin meiosis
True
Meiosis is necessary of sexual or asexual reproduction
Sexual
Meiosis is the key to what
Genetic variability
Meiosis happens in how many stages
2
What happens in prophase 1 and 2
The nucleus dissolves, chromatin becomes chromosomes, centrioles arrive at opposite poles, and a spindle apparatus forms
What happens in metaphase 1 and 2
Homologous chromosomes pair up along the center of the cell and each spindle apparatus attaches to the half of the chromosomes
What happens in anaphase 1 and 2
Homologous chromosomes are pulled to opposite sides of the cell and a furrow begins to form
What happens in telophase 1 and 2
The cell divides into two cells, nuclei reappear, and chromosomes become chromatin
What do we have after Meiosis 1
Two non-identical haploid cells
What do we have after Meiosis 2
Four non-identical haploid cells
What are the differences between Meiosis and Mitosis
- Meiosis is linear, Mitosis is cyclical
- Meiosis goes from 1 cell to 4 cells, Mitosis goes from 1 to 2 cells
- Meiosis goes from diploid to haploid, Mitosis goes from diploid to diploid
What happens after Meiosis
- The haploid cells become gametes: the female called ova, the male called sperm
- Fertilization occurs when two gametes join to become one cells
- A zygote is the new diploid cell that results from fertilization, it is the first cell of a new living thing
What difference in the processes causes meiosis to produce haploid cells but mitosis to produce diploid cells
Meiosis seperates the pairs so they become haploid, Mitosis rips the chromosomes in half so they become diploid
Why is meiosis necessary for sexual reproduction
The haploid cells are needed for fertilization to make a zygote
Why is meiosis the key to genetic variability
One individual can produce 8 million different gametes, one husband and wife can produce 2⁴⁶ genetically unique offspring, and crossing over can increase genetic variability
