Family Patterns Introduction

Copy this table into your exercise book and use the following information to complete it Mitosis Meiosis Where in the body does it occur? How does the number of chromosomes compare between parent and daughter cells? What is the purpose of this sort of cell division?

An overview of the genetic system

How gametes are formed

Let’s make sure that we have all the answers. Mitosis Meiosis Where in the body does it occur? How does the number of chromosomes compare between parent and daughter cells? What is the purpose of this sort of cell division? Only in the gonads All cells except in the gonads - Ovaries and testes Exactly the same – the cells are identical in every way Daughter cells have ½ the number of chromosomes To produce identical cells so that each cell has a full set of instructions and can carry out the same functions (ie for growth and repair) To halve the number of chromosomes so that when gametes join (fertilisation) they have the correct number of chromosomes and also to produce variation

What determines the sex of humans

Meiosis and twins

Cystic Fibrosis

Huntingdon’s Disease