Integumentary system - hair, Biology

HAIR

  1. Presence of hair is main feature of mammals, absent in whale fish.
  2. Soft hair in embryo of animals are lanugo. Study of hair is tricology.
  3. Part of hair which is outside epidermis is shaft.
  4. Inner part remains in hair follicle is hair bulb or root.
  5. Follicle at its base form hair papillae, rich in b.v. and nerve suply.
  6. In these cells power of division present through out life.
  7. Growth of hair depends on these cells. Around hair scally cuticle present.
  8. Outer part of hair is cortex, fibrous in nature, melanin present in it when melanin is disappeared and tiny air bubbles come, hair turns white.
  9. Inner part of hair is medulla made up of air filled, round, closely attached cells.
  10. Hair is fixed in hair follicle by Henle's layer, Huxley's layer & Hyaline's layer.
  11. Hair follicle is placed obliquely in dermis.
  12. Attached to epidermis by arrector pilli or elevator pilli muscle or arrector polirum muscle.
  13. This muscle is connected to sympathetic nervous system.
  14. Arrector pilli are absent in eye brow, arm's pit & other parts.
  15. In cold and fear, muscle is contracted, hair become straight i.e. cutis anserina.
  16. This time skin looks like goose flesh or duck bumps.
  17. It is under control of adrenalin. In rabbit & cat and other sliff hair are vibrissae.
  18. In rabbit, thigmo receptor, meant to judge burrows at night.
  19. In cat & rabbit if we cut vibrissae locomotion is uncontrolled & it can not run fast.
  20. If we remove all hair from skin, sweating is increased.

1269_hair structure.png

Posted Date: 10/1/2012 4:35:38 AM | Location : United States







Related Discussions:- Integumentary system - hair, Assignment Help, Ask Question on Integumentary system - hair, Get Answer, Expert's Help, Integumentary system - hair Discussions

Write discussion on Integumentary system - hair
Your posts are moderated
Related Questions
Draw a class diagram: You are required to provide a practical implementation in C++ for the following class diagram. You have to provide the solution in the form of classes in

state 3 ways human activities add carbon to the atmosphere

Explain Antiarrhythmic Drugs? Amiodarone may be considered in VT/VF that is refractory to shock. It might be given if the third shock is not successful. The dose is 300 mg IV i

Q. Common Disorders of Coronary Heart Diseases? We shall deal with different types of heart diseases, their- etiology, symptoms, complications, as well as, nutrition and dietar

1. Write general characters of phylum mollusca and classify it upto classes, giving at least two examples of each class.

High blood pressure (hypertension) has gained considerable significance because it will eventually damage end organs like the heart, brain, kidneys and the eyes. It is estimated th

Family  is the Basic Unit of Society   Each child within a family needs love and security to develop feelings of  trust and self esteem. Each child is a unique individual who h


Determine about the Nervous System and Behaviour Damage to certain parts of the brain will be reflected as behaviour deficits. For example, damage to the temporal lobe may affe

Explain the Pour Plate Method Isolated colonies can also be obtained by pour plate method. The method involves mixing of small volume of microbial suspension with molten nutrie