University:
Yeshiva University
Course:
3207C | Cell Biology
Academic year:

2020
Views:

315

Pages:

2
Author:

genanta0v

Amoeba Sisters - Recap of Meiosis 1. The purpose of meiosis is to make gametes, also known as sperm and egg cells. In humans, your body cells have 46 chromosomes. How many chromosomes are in a sperm or egg cell if, when they come together to form a fertilized zygote, there are 46 chromosomes? Write the correct number of chromosomes next to the sperm and egg. 2. Interphase must occur once before meiosis can happen. (Same thing for mitosis). What would happen if interphase didn’t occur first? 3. A cell that begins meiosis has 23 chromosomes inherited from the mother (shown in green in the cartoon below) and 23 chromosomes inherited from the father (shown in blue in the cartoon below). In the process of meiosis, chromosomes begin to match up in homologous pairs. How would you know if two chromosomes were homologous? The cell would not grow. They would be very similar in shape and size. 23 4. Crossing over is a very important event in Prophase I of meiosis! What happens during crossing over and what is the significance? Segments of chromosomes are exchanged, this is significant because this creates variation of traits in parent genes 5. Meiosis does PMAT twice! That means there is a prophase I and a prophase II. There is a metaphase I and a metaphase II. Etc… If the cartoon below has chromosomes in the middle of the cell, how would you know whether it was in metaphase I or metaphase II? In metaphase 1 chromosomes are lined up with homologous pairs and with metaphase 2 chromosomes are lined up in the middle of the cell. 6. Meiosis does not always occur without any difficulties. Describe what occurs during nondisjunction and the effect on the resulting cells. Chromosomes might not separate correctly and this can cause genetic recombination. ___ ___ Can you finish the meiosis chain? Write the correct stage that comes next in each circle. Don’t forget the number that comes after the stage name! Then write any details about what this stage looks like next to it. Now let’s play, “Which Clip Would That Be Said In?” Keeping mitosis and meiosis separate in your mind can be a bit tricky. Read the following speech bubbles. Determine whether they would be correctly placed in the mitosis clip, the meiosis clip, or both by drawing a line to the correct place in the Venn diagram. Interphase occurs once before the process begins. Process ends with identical cells. Produces gametes. Produces 4 cells that each have 23 chromosomes. Crossing Over occurs. Process is important for growth and repair.