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lara [203]
1 year ago
7

ancestors of giraffes with shorter necks could not reach branches high up in trees for food. this led to selection for longer-ne

cked giraffes.
Biology
1 answer:
hichkok12 [17]1 year ago
7 0

With shorter necks, giraffe ancestors could not reach food-containing branches on tall trees. This resulted in the directional selection of giraffes with longer necks.

 

<h3>Why is choosing a direction necessary? </h3>

It nearly appears obvious that the giraffe's long neck developed as a result of a lack of food in the lower branches of trees. The giraffe has a significant advantage because it is taller than any other mammal and can feed where few others can. 

When compared to modern giraffes, the giraffe's ancient predecessors had a shorter neck. The plants that were lying at a higher level were inaccessible to them. Giraffe phenotypes have changed in various ways, and now have long necks to reach vegetation that is higher up. The extreme form is chosen above other features in directional selection. It was decided to choose the long-necked giraffe over the short-necked.

 

To know more about direction selection for longer necked giraffes visit:

brainly.com/question/3738222

#SPJ4

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A connective tissue disorder in which dense irregular connective tissue fails to form properly will affect the formation of
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<h3>What is connective tissue?</h3>

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Whoever can ancer this question in your own words i will give you 5 star and put thanks as in hart you, please I NEED HELP THIS
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Answer:

In case of a physical support there is a bone system involved, in case of the maintenance of the  body weight there is  wide spectrum of thyroid hormones as well as leptin and ghrelin, according to the recent studies.

Explanation:

There is a whole spectrum of physiological  body systems involved in the maintenance of the body weight in humans, as well as metabolism.  One of the most important hormones are thyroid hormones. According to the most recent studies, the major role there is an adequate function of the digestive system as well. The most important digestive-related hormones are leptin and ghrelin.

In case of the physical protection of the human body weight the major role have bones, cartilages and ligaments. All of the aforementioned structures support the human body organs and other structures. In case of skeleton, it has been estimated that it consists of 206 bones. In case of younger individuals, the human skeleton has a greater protective effect to other body systems. In case of bones, its main role is to have a rigid support for internal organs and other body structures. In that way, the body weight is is supported against the force of gravity. Additonaly, it provides a support for muscles to maintene their movements as ligaments bind to the distal and proximal parts of the corresponding bones. If we analyze the upper parts of skeleton, their promienent role is in the lifting and carrieng objects etc. The lower parts of the skeleton are involved in a variety of functions such as walking, runinng, playing sports etc.

In case of internal portions of skeleton, it is necessary to outline the major role of skeleton for example in the abdominal and peritoneal cavities. In these cases, the role of skeleton is to act protectively to the contained organs in those cavities. In case of bones themselves, they act as aa storage site for diverse minerals (calcium, phosphate etc. ). The bone marrow is a storage site for the production of blood components producing cells.

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Ghrelin is a fast-acting hormone. It has the role in the meal initiation. It is known that leptin resistant individuals are obese. Ghrelin is a 28-amino acid that stimulates appetite and the release  of growth hormone. Nearly 70 percent of ghrelin is secreted by the stomach and small intestine. Ghrelin has a major role in white adipose tissue where it stimulates adipogenesis, fat storage enzymes and increases trygliceride concentration. It decreases lipolysis.

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