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

Zinc (zn) - micronutrients, Zinc (Zn) - Micronutrients In its function...

Zinc (Zn) - Micronutrients In its function in some enzyme systems, zn 2+ resembles Mn 2+ in that it brings about substrate binding and conformational changes in enzymes. A n

Relevance of food packaging, Q. Relevance of food packaging? To unders...

Q. Relevance of food packaging? To understand the relevance of food packaging, it is necessary for us to understand how spoilage reduces the availability of food. In the deve

What are the forces that make water to flow, What are the forces that make ...

What are the forces that make water to flow within the xylem from the roots to the leaves? Water enters the roots because of the root pressure and a water column is maintained

Bone formation, 3 main stages of bone formation, and explain the process of...

3 main stages of bone formation, and explain the process of these 3 stages.

Are coloured bodies composed of proteins and dna, Chromosomes, coloured bod...

Chromosomes, coloured bodies, are composed of proteins and DNA; so are chromatids. At metaphase I there are 46 chromosomesaligned in pairs along the human cells equatorial plate. A

Cardiovascular endurance component for physical fitness, Define Cardiovascu...

Define Cardiovascular endurance Component for physical fitness? In our previous section on work capacity, concepts of aerobic capacity Vo2 max were described. Cardiovascular en

Define class turbellaria - flatworms, Define Class Turbellaria - Flatworms ...

Define Class Turbellaria - Flatworms ? Members of these two Classes are known as the flukes. Flukes are parasitic flatworms that inhabit tropical areas like Southeast Asia and

Define sample titration for estimation of reducing sugar, Define Sample Tit...

Define Sample Titration for Fehling Soxhlet Method Dilute the given sample glucose solution in 100 ml volumetric flask to the mark with distilled water. Pipette 5 ml of Fehling

Agro industrial-steam treatment, Steam treatment Steam treatment of cro...

Steam treatment Steam treatment of crop residues under pressure has recently opened a new vista for their nutritional improvement especially in the situation when steam availab

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