Those who have Down syndrome have three full copies of chromosome 21, a condition termed primary Down syndrome.

familial Down syndrome Human condition caused by a Robertsonian translocation in which the long arm of chromosome 21 is translocated to another chromosome; tends to run in families.

TLS Online TPP Program

#Id: 9546

#Unit 11. Evolution and Behavior

In the most famous example of Lamarck’s theory, giraffes must have stretched their necks to reach foliage above them, and so their necks were lengthened

The longer necks were inherited, and over the course of generations, this process was repeated, and their necks got longer and longer. 

TLS Online TPP Program

#Id: 9547

#Unit 11. Evolution and Behavior

TLS Online TPP Program

#Id: 9548

#Unit 11. Evolution and Behavior

Neo-Lamarckism - August Weismann

cut off the tails of mice for many generations and showed that this mutilation had no effect on the tail length of their descendants.

TLS Online TPP Program

#Id: 9549

#Unit 11. Evolution and Behavior

Darwin’s evolutionary theory 

Evolution as such is the simple proposition that the characteristics of organisms change over time. 

TLS Online TPP Program

#Id: 9550

#Unit 11. Evolution and Behavior

Postulate of Darwin

Geometric increase 

Limited food & Space

Struggle for existence 

Variation 

 Natural selection

Inheritance of useful characters

Speciation

TLS Online TPP Program

#Id: 9551

#Unit 11. Evolution and Behavior

Darwin’s evolutionary theory - Common descent