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

Chorionic villus sampling (cvs), CHORIONI C VILLUS SAMPLING (CVS)  - CV...

CHORIONI C VILLUS SAMPLING (CVS)  - CVS is done during 8th-10th week of pregnancy when abortion is safe. For CVS cells are sucked into a catheter passed through the cervix.

Does ascaris lumbricoides present an intermediate host, Q. Does Ascaris lum...

Q. Does Ascaris lumbricoides present an intermediate host? An Ascaris is a monoxenous parasite, its life cycle is dependent only on one host and so it doesn't have intermediate

What is the normal duration of the menstrual cycle, What is the normal dura...

What is the normal duration of the menstrual cycle? How does the calendar contraceptive method work? The normal duration of the menstrual cycle is 28 days but it can vary betwe

Cholesterol, Cholesterol Cholesterol is found in several of the animal ...

Cholesterol Cholesterol is found in several of the animal foods we eat, involving cheese, eggs, and red meat. Just animal cells utilize and synthesize cholesterol. Click the bu

Explain the class reptilia perform gas, Do beings of the class Reptilia per...

Do beings of the class Reptilia perform gas exchange in the same way amphibians do? These beings do not have permeable skin so they do not make cutaneous respiration such as a

Classification of different agro-industrial by-products, Classification of ...

Classification of Different Agro-Industrial By-Products The agro-industrial by-products can be grouped according to the content of nutrients namely: (i) Energy rich supplem

Determine the significance of mesoglea, Determine the significance of Mesog...

Determine the significance of Mesoglea. The jellylike layer found between endodermal and ectodermal cell layers of diploblastic organisms. It acts as a type of cement holding t

What is sex-linked traits in genetics, What is Sex-linked Traits in genetic...

What is Sex-linked Traits in genetics? The X-chromosomes carry genes for traits other than sex characteristics. Morgan discovered these sex-linked traits while observing the in

Show major signs of diabetes, Q. What are the three major signs of diabetes...

Q. What are the three major signs of diabetes? The three major signs of diabetes mellitus are known as the diabetic triad- polydipsia, polyuria and polyphagia. Polyuria is t

What is the life cycle of the hookworms, What is the life cycle of the hook...

What is the life cycle of the hookworms? Adult hookworms within the human intestine release eggs that are eliminated with the human feces. Under adequate conditions of moisture

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