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sergiy2304 [10]
3 years ago
15

The _________ is the site of the _________ which is the first site of hematopoiesis in the developing embryo.

Biology
1 answer:
Ghella [55]3 years ago
6 0

Answer: D

Explanation:

During embryogenesis, hematopoiesis begins in week 3 in the Yolk Sac, in Pander´s Island or Wolff´s Island, commonly known as the "blood islands". These blood islands develop from the umbilical vesicle, allantois, and chorion. In week 5, blood production starts on the fetal liver, and finally, at week 12 it begins in the bone marrow, spleen and, thymus.

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A woman who has sickle cell anemia passes this disease on to her offspring. This means that the mutation for sickle cell anemia
Kobotan [32]

The right option is; A) gametes

Gametes are reproductive cells (male (sperm) or female (eggs)) that contain only half the usual number of chromosomes and unite during sexual reproduction to produce a new cell (zygote). The mutation for sickle cell anemia occurs in the woman’s gamete (eggs) and this type of mutation is known as germline mutation; a mutation that occur in the germ (reproductive) cells and can be passed on to an organism’s offspring.

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3 years ago
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The male reproductive parts of a flower are called
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The correct answer in this question is letter B. The male reproductive parts of a flower are called stamens. It is composed of an anther and a filament. The pollen, which is located in the anther, contains the male reproductive cells.
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4 years ago
Ozone in the troposphere is necessary to protect Earth's surface from harmful UV radiation.
romanna [79]

Answer:

False

Explanation:

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2 years ago
Where do the branches of the bronchial tree ultimately end? 2. list the steps of the pulmonary circuit of the cardiovascular sys
Aneli [31]
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2. Blood flows from the left atrium; mitral (bicuspid valves), the left ventricle, aortic valve, aorta, veins and heart, right side of the heart, superior and inferior vena cavae, right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary trunk, pulmonary artery, lungs, pulmonary veins, then back to the heart...

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4. The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and the bronchioles. Blood moves in and out of the lungs throgh the pulmonary arteries and veins that connect to the heart.

5. The cartilage rings of the trachea
They are strong but flexible tissues which support the trachea or the windpipe while still allowing it to move and flex during breathing. Additionally these cartilage rings are C-shaped to provide room for the esophagus, which lies along the back side of the trachea.

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3 years ago
What is the purpose of the coronary artery and what results if there is blockage in this vessel ? cousrse hero?
tresset_1 [31]
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3 years ago
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