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chubhunter [2.5K]
3 years ago
7

During which period did manual fist appear A. Pleistocene B. Carboniferous C. Cretaceous D. Jurassic

Biology
1 answer:
steposvetlana [31]3 years ago
3 0
<span>
d jurassic period is the correct answer</span>
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Plant cells have mitochondria, which use glucose to produce ATP. Where does the glucose originate?
Romashka [77]

Plant produces glucose in the chloroplast through the process of photosynthesis. Calvin cycle is basically the biological process through which glucose is produced. The steps involved are as follows:

1. Absorbed CO2 is added to RuBP and 6C sugar is formed.

2. Breaking of 6C sugar into two  3-phosphoglycerate molecules

3. ATP gives phosphate group  to form 3-phosphoglycerate which is later on converted into 1,3-biphosphoglycerate.

4. Electons are required by 1,3-biphosphoglycerate to an aldehyde called glyceraldehyde-3-phosphate or G3P and these electrons are donated by NADPH

5. Enzyme aldolase uses two molecules of G3P to produce 6 C sugar called  fructose-1,6-biphosphate which is further converted to fructose-6-phosphate

6. Enzyme  isomerase converts fructose-6-phosphate to glucose-1-phosphate


7 0
3 years ago
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Select the correct answer.
damaskus [11]

Answer:

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4 0
3 years ago
Which of the following statements best describes the role of hormones in the body? Hormones send chemical signals throughout the
il63 [147K]

Answer:

Hormone production and release are primarily controlled by negative feedback. In negative feedback systems, a stimulus elicits the release of a substance; once the substance reaches a certain level, it sends a signal that stops further release of the substance. In this way, the concentration of hormones in blood is maintained within a narrow range. For example, the anterior pituitary signals the thyroid to release thyroid hormones. Increasing levels of these hormones in the blood then give feedback to the hypothalamus and anterior pituitary to inhibit further signaling to the thyroid gland, as illustrated in Figure 18.14. There are three mechanisms by which endocrine glands are stimulated to synthesize and release hormones: humoral stimuli, hormonal stimuli, and neural stimuli.

Explanation:

Hyperthyroidism is a condition in which the thyroid gland is overactive. Hypothyroidism is a condition in which the thyroid gland is underactive. Which of the conditions are the following two patients most likely to have?

Patient A has symptoms including weight gain, cold sensitivity, low heart rate and fatigue.

Patient B has symptoms including weight loss, profuse sweating, increased heart rate and difficulty sleeping.Humoral Stimuli

The term “humoral” is derived from the term “humor,” which refers to bodily fluids such as blood. A humoral stimulus refers to the control of hormone release in response to changes in extracellular fluids such as blood or the ion concentration in the blood. For example, a rise in blood glucose levels triggers the pancreatic release of insulin. Insulin causes blood glucose levels to drop, which signals the pancreas to stop producing insulin in a negative feedback loop.

Hormonal stimuli refers to the release of a hormone in response to another hormone. A number of endocrine glands release hormones when stimulated by hormones released by other endocrine glands. For example, the hypothalamus produces hormones that stimulate the anterior portion of the pituitary gland. The anterior pituitary in turn releases hormones that regulate hormone production by other endocrine glands. The anterior pituitary releases the thyroid-stimulating hormone, which then stimulates the thyroid gland to produce the hormones T3 and T4. As blood concentrations of T3 and T4 rise, they inhibit both the pituitary and the hypothalamus in a negative feedback loop.

3 0
3 years ago
How do cells behave in a multicellular protist?
Sindrei [870]

Answer:

2.They exhibit cell specialization.

Explanation:

A protist is an eukaryotic organism that can either be unicellular or multicellular. In the multicellular protist i.e. many cells, different types of cells are needed to bring about the organism's life processes. The different types of cells perform a specific different function in the organism.

The way that an organism makes it cells specialized to perform different functions is called Cell Specialization or differentiation. All multicellular organism, including a multicellular protist, contain many cells that have been specialized to perform different functions. Hence, the many cells of a multicellular protist will exhibit specialization in order to perform varying functions in the organism.

7 0
3 years ago
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A specimen collection helps a scientist do an experiment by:
slavikrds [6]

Answer: B. providing access to objects that are hard to find

Explanation: A specimen can be simply refered to as a sample of blood, tissue, fluid or a piece of a matter which scientist take or obtain to have a better look (study) at it in a lab.

Specimen collection is the process involved in getting or obtaining these samples for better analysis in a lab. This process help scientist get, obtain or have access to samples or objects that are not easily accessible.

Therefore Specimen collection helps scientist carry out experiment by providing access to objects that are hard to find.

6 0
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