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2 years ago

2. How has scientific understanding about the composition of the universe changed over time? Select the two correct answers.

1 answer:

6 0

Answer: The percentage of unknown material has grown in scientists estimates since the 1970’s; the percentage of dark matter has shrunk in scientists estimates since the 1980s

Explanation:

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Which term names the energy-containing molecule that is the immediate result of photosynthesis? A. ATP B. carbon dioxide C. wate

Mnenie [13.5K]

D because during photosynthesis, glucose is what is made inside the plant.

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2 years ago

1. In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are microtubules. 2. Ma

yulyashka [42]

Answer:

1) In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are microtubules.

2) Many cell organelles, most notably the nucleus, are anchored by intermediate filaments which are assembled from a diverse class of proteins.

3) Centrosomes are sites where protein dimers assemble into microtubules.

4) The extension of pseudopodia in amoeba is due to the regulated assembly and destruction of microfilaments.

5) The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the intermediate filaments.

6) During muscle contractions, myosin motor proteins move across tracks of microfilaments.

Explanation:

The cytoskeleton is a very important element of the cell, and is composed of three different structures: microtubules, intermediate filaments, and microfilaments.

Microtubules are structures in the shape of hollow tubes that give shape to the cell. Microtubules also participate in cell motility by providing a route for the organelles to move through.

Intermediate filaments are the only ones that do not participate in cell motility: their main function is to provide mechanical support for the plasma membrane.

Microfilaments are a key component in cell motility, and also associate with myosin (a protein) to produce muscle contraction. Microfilaments also give the cell the ability to grow pseudopods.

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3 years ago

Read 2 more answers

A 9-month-old child with cystic fibrosis does not like taking pancreatic enzyme supplement with meals and snacks. The mother doe

Fantom [35]

Answer:

The correct answer is 2. "the child needs these pancreatic enzymes to help the digestive system absorb fats, carbohydrates, and proteins".

Explanation:

90% of patients with cystic fibrosis get the pancreatic enzymes supplement because of their pancreatic insufficiency. These enzymes are released in the intestine and help to digest food.

The enzymes´ principal functions are:

- To digest carbohydrates, proteins, and fats;

- To help to gain weight;

- To promote the absorption of nutrients.

To get an appropriate corporal weight and an improved lungs´ functioning it is important to take the enzyme supplement with every meal. It reduces bad absorption and improves nutrition.

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3 years ago

Proto‑oncogenes are genes that have the potential to become oncogenes through either mutation or an increase in expression. Clas

algol [13]

Answer:

Proto-oncogenes

These genes code for protein that normally promote cell division
Mutations that increase activity of these genes may lead to cancer

Tumor suppressor genes

These genes code for protein that normally prevent uncontrolled cell division
Some products of these genes normally function in repairing damaged DNA

Mutation that decrease activity of these genes may lead to cancer.

Explanation:

Proto-oncogenes are group of genes that ordinarily help cells develop. At the point when a proto-oncogene mutates or there are such a large number of duplicates of it, it turns into a "terrible" quality that can turn out to be forever turned on or activated when it shouldn't be. At the point when this occurs, the cell becomes wild, which can prompt malignant growth. This terrible quality is called an oncogene.

Tumor suppressor genes are normal gene that hinder cell division, fix DNA missteps, or tell cell when to undergo apoptosis (die). At the point when tumor suppressor gene don't work appropriately or inactivated, cells can develop uncontrollable growth, that ultimately lead to cancer.

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3 years ago

What is the maximum number of white blood cells allowed in a leukocyte-reduced unit of red blood cells?

SOVA2 [1]

Answer:

Explanation:

What is the number of white blood cells permitted in a unit of leukoreduced red cells? 8 g/dL owing to chemotherapy with a drug known to cause bone marrow depression and immunodeficiency.

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1 year ago