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quester [9]
3 years ago
15

The theory of __________ proposed that a series of catastrophes or mass extinctions followed by repopulation could explain why s

pecies change over time.
Biology
1 answer:
Roman55 [17]3 years ago
6 0
The theory of evolution proposed that a series of catastrophes or mass extinctions followed by repopulation could explain why species change over time
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Products of cellular respiration Products of cellular respiratiihv
nikdorinn [45]

Cellular Respiration is essentially Photosynthesis in reverse, but without the need for solar energy and chlorophyll.  Cellular Respiration take glucose and oxygen (the reactants) and reacts to produce Carbon Dioxide, Water, and ATP (the products).

3 0
2 years ago
Match each of the four barriers of innate immunity with its mode of action.
serg [7]

The matches are

A. anatomical barrier   is matched with 1. secretion of sweat, saliva,  and tears.

The epithelium is a physical barrier constituting one of the first defenses against infectious agents. The desquamation of the epidermis thus eliminates bacteria or other infectious agents that have adhered to the surface of the epithelium. In the digestive tract and the respiratory tract, the movement operated by the peristalsis or the eyelashes contribute to the elimination of the infectious agents. The intestinal flora prevents colonization by pathogenic bacteria acting in particular by competition for nutrients. Tears and saliva also help prevent infection of the eyes and mouth, respectively.


B. physiological barrier   is matched with 4. changes in pH and  temperature.

In addition to this physical (or anatomical) barrier, the acidic pH and low moisture content of the stratum corneum, and the skin temperature below 37 ° C, are detrimental to bacterial growth. Finally, the presence of antimicrobial peptides and lipids make the epidermis a true defender against infection.


C. phagocytic barrier  is matched with 3. signaling to macrophages.

Macrophages are cells belonging to white blood cells (leucocytes), which infiltrate tissues. They come from the differentiation of circulating blood leukocytes, monocytes. Monocytes and macrophages are phagocytes and are therefore capable of phagocytosis.

They participate in innate immunity as a non-specific defense, but are able to participate in adaptive immunity via opsonization.


D. inflammatory barrier  is matched with 2. secretion of chemicals.

In an inflammatory reaction, blood flow increases at the lesion area. The blood vessels become more permeable thanks to vasodilator chemical substances, which allows the migration of cells from the blood to the tissues (the call is made using chemokines). The first cells arriving at the site of inflammation are often neutrophils, then macrophages arrive and then lymphocytes if there is immune stimulation.



3 0
3 years ago
Salt concentration would be an example of what type of factor in an ecosystem? A. food production B. abiotic C. biotic
stira [4]
Hello,

Here is your answer:

The proper answer to this question is option C "<span>biotic".

Here is how:

Salt is consider a biotic factor because of it concentration which makes it a factor of the ecosystem.

Your answer is C.

If you need anymore help feel free to ask me!

Hope this helps!</span>
7 0
3 years ago
Earth's climate systems are driven by the electromagnetic radiation from the sun, as wells as its reflection, absorption, storag
ivann1987 [24]

Answer:

(A) True

Explanation:

The sun is producting the electromagnetic radiation which is the primary energy source on Earth and the driver of the entire climate system.

In general the sun is the source of energy that drives all life on Earth. This energy governs the weather, ocean currents and the hydrological cycles.

Without the continuous influx of sunlight and heat, life on Earth would cease to exist. The sun sets off the hydrological cycle, causing it to constantly evaporate into the atmosphere, from which it falls back to Earth.

8 0
3 years ago
What occurs after sunlight is absorbed by a chloroplast?
OLga [1]

Answer:

B

Explanation:

A cannot be true as photosynthesis requires carbon dioxide and water and uses light energy to break bonds and form oxygen and glucose

C cannot be true as chloroplasts contain chlorophyll which gives the cell its green colour by not absorbing green wavelengths of white light

D is not right as I do not believe photosynthesis is a basic function

4 0
2 years ago
Read 2 more answers
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