An organelle is a function in the body.
Classification is a method of grouping things together based on common qualities. Animal classification is critical since it aids in the identification and naming of all species on the planet. Animalia, Chordata, Mammalia, Primata, Hominidae sapiens are the classifications for humans.
LAMARCK's THEORY
Jean Baptiste Lamarck (1744-1829) proposed a theory which was published in "<em>Philosophie Zoologique"</em> (1809). This theory is simply known as Lamarckism. It has two main postulates:
1. Use and disuse of organs
2. Inheritance of acquired characters.
Example
He explained his theory by giving the examples:
1. Neck length of Girrafes
2. Webbed toes of water birds, and
3. Wings of penguins
Explanation
Lamarck explained that water birds use toe for swimming, with the passage of time webbed were developed in their toes. these features were then transferred to their offspring.
Drawback
Lamarck theory was based on natural observation. It did not explain the genetic basis of such characteristics.
Answer:
natural barriers
Explanation:
skin, mucous membrane, tears, earwax, muscus, stomach acid
