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

Determine the function of iron for athletes, Determine the function of Iron...

Determine the function of Iron for athletes? Iron carries oxygen and is another important mineral for athletes. It also affects oxygen transport and aerobic metabolism as a com

Characteristic of ecotone, Characteristic of Ecotone A general charact...

Characteristic of Ecotone A general characteristic of ecotone is that it has sufficiently greater number of species and the diversity of most of the species at times is higher

How are gametes formed in the pteridophyte life cycle, Q. How are gametes f...

Q. How are gametes formed in the pteridophyte life cycle, by mitosis or meiosis? What is the type of meiosis that occurs in pteridophytes? In pteridophytes gametes are made by

Resemble the homozygous recessive parental, A dihybrid cross yields 320 F2 ...

A dihybrid cross yields 320 F2 offspring. How many are expected to resemble the homozygous recessive parental?

Difference between hazard and disaster, 1.      Hazard Is An Extreme Event ...

1.      Hazard Is An Extreme Event Whereas Disaster Is Its Consequence. 2.      A hazard can occur without human interference but it may become a disaster on account of careless

What are the approaches to the design of retaining walls, What are the appr...

What are the approaches to the design of retaining walls? The approach to the design of retaining walls can be started as follows: a. Chosse a trial dimension of the wall

Define protein as an energy source, Define Protein as an energy source? ...

Define Protein as an energy source? Proteins contribute to the body's energy need. If diet does not furnish enough calories from carbohydrates and fats, proteins are catabolize

Zoology, The structure and formation of schizocoelous

The structure and formation of schizocoelous

What is a community, What is a community? What is the difference between th...

What is a community? What is the difference between the concepts of community and population? A community is a set of the populations of living beings that live in the same reg

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