Determination of limb polarities, Biology

Assignment Help:

Determination of Limb Polarities

The limb pattern is characterized by three axes (or polarities) as displayed in diagram:

 (1) The direction from the shoulder (or hip) to the digits is the proximal-distal (P-D) axis.

(2) The cranial (head) side of the limb is anterior and the caudal (tail) side is posterior. The direction from the former to the latter side is anterior-posterior (A-D) axis.

(3) The third axis is the dorsal-ventral (D-V) axis which indicates the direction from the upper (dorsal) to the lower (ventral) side of the limb.

In your own hand the thumb is anterior and little finger posterior. The back of the hand marks the dorsal and palm the ventral side. You should also notice that the respective contralateral forelimbs and hindlimbs develop as mirror images of each other. For example, your right hand and foot are mirror images of the left hand and foot, respectively.


Related Discussions:- Determination of limb polarities

How many germ layers originate the body of platyhelminthes, Q How many germ...

Q How many germ layers originate the body of platyhelminthes? In relation to this characteristic how are these animals classified? Platyhelminthes are the first triploblastic a

What is the most probable inheritance pattern of a trait, What is the most ...

What is the most probable inheritance pattern of a trait with gaussian proportional distribution of phenotypical forms? If a trait statistically has a normal (bell-shaped curve

Function of the cornified layer of the skin, What are the main functions of...

What are the main functions of (a) the basal (Malpighian) layer, (b) the cornified layer of the skin?   (a) The basal (Malpighian) layer makes new skin cells and the pigment

Define integrity of cartilage function of manganese, Define Integrity of ca...

Define Integrity of cartilage Function of Manganese? Mn plays an important role in proteoglycan biosynthesis, which is essential for the integrity of cartilage. Bone defects ha

What are the plant cell vacuoles, Q. What are the plant cell vacuoles? And ...

Q. What are the plant cell vacuoles? And what are their functions? And what is the covering membrane of the vacuoles called? Plant cell vacuoles are cell structures delimited b

Psychosocial problems, PSYCHOSOCIA L PROBLEMS  - 1 .       Accidental...

PSYCHOSOCIA L PROBLEMS  - 1 .       Accidental injury - Automobile accidents are no. 1 killers of adolescents, as they drive often fast. 2 .       Depression - I

Flowering and endogenous rhythms, Flowering and Endogenous Rhythms Th...

Flowering and Endogenous Rhythms The last four decades of studies in animals and plant physiology have clearly established the existence of a biological clock mechanism to me

Explain the history of nutrition, Explain the History of Nutrition? Kno...

Explain the History of Nutrition? Knowledge of human nutritional needs and relationship between diet and health was placed on a modern scientific footing only since the 19th ce

What is single ventricle physiology, What is Single Ventricle Physiology ? ...

What is Single Ventricle Physiology ? In complete correction of a congenital cardiac condition, it is ideal to have two ventricle correction (Pulmonary and systemic ventricles

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