Week 10
Class 1: Cell division
Cell division is like a magical trick that happens
inside our bodies all the time! It helps our bodies
grow, repair when we get hurt, and even helps
make new life. It's like a dance that happens inside
each cell, where the cell splits into two smaller
cells. It's very important because it helps make
sure our bodies work the way they should. It
happens in tiny little creatures like bacteria, and
even in big animals like elephants!
Without cell division, life as we know it wouldn't exist.
Our cells can divide in two ways, they are called mitosis and meiosis. Today we will start by learning about the mitosis process, when it happens, and the stages it has.
1) Watch the following video about mitosis and answer the questions or complete the missing part of the sentences:
a) How could you define mitosis in a simple way?
b) Mitosis produces ….
c) In which processes is mitosis involved?
d) How many chromosomes does a normal cell have?
e) Homologous chromosomes are ...
f) Before mitosis begins, the genetic material must ...
g) How are the daughter cells?
2) As shown in the image, before mitosis begins, the genetic material is duplicated. explain why? (look at the mother cell and the daughter ones)
3) The image below shows the different stages of mitosis for a cell with ONE pair of chromosomes. Create a diagram showing these stages for TWO pairs of chromosomes. Use one color for pair one and a different color for chromosome two and explain in one sentence what is happening in each stage.
You can use the following pages to find information about the stages:
4) Solve the Math and science challenge:
Expert level challenge: SCIENCE & MATH
If bacteria can divide every 20 minutes and initially we have 30 bacteria.
How many bacteria would we have after 3 hours?
Last class we learnt the way in which our body produces cells by dividing a mother cell into two daughter cells. This cell division process, called mitosis, applies for any cell in the body, except for the cells our bodies use to make a baby: eggs or ova in the case of women and sperm in men.
These special cells used in reproduction are
called "gametes." These gametes have half of
the normal number of chromosomes, which is
why they need to join together to make a full set.
Meiosis is the way our bodies create these special gamete cells. It's like a special kind of cell division that happens in our bodies. Through meiosis, our bodies make sure that each new gamete has only half the number of chromosomes as a regular cell, which is what we need to make a baby!
Let's solve these activities in order to understand Meiosis in a deeper way:
1) Visit the Ducksters site and explain the terms "Haploid" and "Diploid"
2) Draw and explain what is crossing over?
why are siblings different?
3) Go to the EasyScienceforKids website and write the most important characteristics of meiosis (what is it? how are the daughter cells? how many stages?)
4) Visit the Britannica kids website and draw the Meiosis overview diagram in your notebook
5) When a man and a woman become parents, the process of fecundation happens. The sperm enters the egg and a new cell is formed. This first cell is called the zygote. Draw the fertilization process as an equation: ovum + sperm = zygote and say the number of chromosomes each one has:
Class 2: Meiosis
