Heredity
Chapter Name : Heredity And Evolution |
Sub Topic Code : 103_10_09_02_05 |
Topic Name : Heredity |
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Sub Topic Name : Sex Determination |
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Introduction
Sex determination can depend on different criteria for different species, like temperature, genes etc.
Pre-Requisites:
How do traits get expressed?
Activity:
Cross an XX with an XY in your notebook and work out the gene combinations of the first progeny F1. We see there are 50% chances of a human progeny of being a male/female. We also see that the sex of the progeny depends on the male parent.
Real Life Question:
In many countries, the mother is held responsible for not being able to give birth to boys. Is it really that the sex of the progeny depends on the mother?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Sex chromosome | A pair of chromosomes that determine the sex of an individual. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Read Mendel’s experiment. Try to do the same with other species and with the sex chromosome. | Understanding sex determination. |
Places to visit :
Biology Lab/Classroom
Practical examples around us
| Examples | Explainations |
|---|---|
| Sex of a lizard baby depends on the temperature. |
What you learn in Theory:
Sex of humans is determined genetically, but this is not true for all organisms.
What you learn in Practice:
Sex of human baby is determined by the father and not by the mother.