Integumentary system - hair, Biology

Assignment Help:

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


Related Discussions:- Integumentary system - hair

What are epithelial tissues, What are epithelial tissues? What are their ge...

What are epithelial tissues? What are their general function and how is that function associated to the features of the tissue? Epithelial tissues, also known as epithelia, are

Define fermented dairy products-butter, Normal 0 false false ...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Annuloplasty with a ring, Annuloplasty with a Ring :  The lings commo...

Annuloplasty with a Ring :  The lings commonly used are Carpentier- Edwards and Cosgrove's flexible half ring. The rings are C shaped and have incomplete circles to accommoda

Define body mass index (bmi), Define Body Mass Index (BMI)? Weight for ...

Define Body Mass Index (BMI)? Weight for height as a marker of nutritional status has the advantage that it is independent of other factors that affect foetal outcome such as m

Safety, S a f e ty, ethical and welfare considerations Development ...

S a f e ty, ethical and welfare considerations Development of transgenic organisms is proceeding in an environment of intense public debate about safety, environmental impa

Classify biomaterials and list some examples, Classify biomaterials and lis...

Classify biomaterials and list some examples. Biologic classification is based on tissue response and systemic toxicity effects of the implant and is divided into three classes

Acid indigestion, Acid indigestion It is also known as ruminal acidosis...

Acid indigestion It is also known as ruminal acidosis, acute carbohydrate engorgement, rumen over load or lactic acidosis. Ingestion of large quantities of highly fermentable c

What is the main theory opposed to evolution, What is the main theory oppos...

What is the main theory opposed to evolution? The major theory that opposes the evolution theory on the description of how species emerged (phylogenesis) is fixism.

Explain class angiospermae, Class angiospermae (Flowering plants) Flowers...

Class angiospermae (Flowering plants) Flowers are the reproductive structures. Ovules are protected within ovary, xylem vessels are present. After fertilisation the ovary develop

Define interaction of vitamin c with riboflavin, Define interaction of Vita...

Define interaction of Vitamin C with Riboflavin? The two coenzyme forms of riboflavin are FMN and FAD. They are found in a large number of systems which function in the metabol

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd