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inn [45]
2 years ago
11

How have hominid skulls changed over time? What are some of the reasons for those changes?

Biology
2 answers:
liberstina [14]2 years ago
7 0

Answer:

The change from the oblong skull and protruding face of ancient humans (right) to the modern rounder skull and retracted face is associated with a sharper bend in the floor of the brain case (lower left), thought to be caused by increased brain size.

Explanation:

Give brainlist me please

erma4kov [3.2K]2 years ago
4 0
<h2><u><em>Skull and face changes define modern humans - Harvard Gazette</em></u></h2>

The change from the oblong skull and protruding face of ancient humans (right) to the modern rounder skull and retracted face is associated with a sharper bend in the floor of the brain case (lower left), thought to be caused by increased brain size.

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They help each other survive in the ocean. The fish help the sea anemone more though.
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Describe how a single amino acid substitution causes hemoglobin molecules to stick together. Use what you know about the structu
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Question: Describe how a single amino acid substitution causes hemoglobin molecules to stick together. Use what you know about the structure of Hb and HbS, the properties of glutamic acid and valine, and how hydrophobicity causes molecules to behave in water.

Answer:

A Single amino acid must be polar to attract, just like water.

Explanation:

Sickle cell is an genetic illness and it is began by a alteration that arises in the beta sub units of the haemoglobin. Haemoglobin is a tetrameric protein made up of 2 alpha sub units and 2 beta sub units and it is the important part of the blood accountable for oxygen passage. Sickle cell is a illness that consequences from a replacement of a polar amino acid identified as glutamate with a non polar one valine at site six of the beta polypeptide component of haemoglobin. The replacement occurs as a consequence of a alteration in one of the bases in the beta-globin gene from adenine to thymine  . As a outcome of this change, the beta polypeptide chains convert sticky in low oxygen circumstances since the valine sticks out of the chain and interrelates with neighboring non-polar amino acids.  

6 0
3 years ago
Differentiate Humoral immunity vs cell mediated immunity
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Answer:

Cell-mediated immunity develops through a network of interactions that results in defense against microorganisms that survive within phagocytes or other cells. The response is initiated by the recognition of intracellular microorganism antigen by T cells through the histocompatibility complex. In the CD8 response, only the target cell carrying the class I associated antigen can be lysed or induced to apoptosis. In another mechanism of the cellular response, CD4 + Th1 T cells activate, for example, cytokine-infected macrophages such as IFN. When a pathogen resists the effects of activated macrophages, chronic infection may develop.

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3 years ago
Identy three advantages and three disadvantages of bioplastics
swat32

Explanation:

<em><u>Advantages of bioplastics</u></em>

1.Less oil is used to produce petrochemical (oil-based) plastics which pose a great risk to the environment.

2.The common bioplastics can be injection molded and shaped to take the same form as traditional thermoplastics. In some cases, the bioplastics are stronger and lighter, too, so they are not necessarily only suitable for very niche applications.

3.Bioplastics are more marketable, for example, their usage may improve the value-add of a product through a green marketing campaign. After all, studies have shown that ‘80% of European customers want to buy products with a minimal impact on the environment,’ so bioplastics may represent a useful argument for brands.

<em><u>Disadvantages of bioplastics</u></em>

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3.Crop-based bioplastics require fertile land, water, fertilizers, and are reliant on weather conditions. This means that the supply of raw materials for bioplastics are at risk of natural phenomena, such as drought.

6 0
3 years ago
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