They require an centrosome and a lysosmes
The sympathetic nervous system releases hormones known as catecholamines which increase the heart rate.
<h3>What is a heart rate? </h3>
it is the number of contractions of the heart per minute.
<h3>What are catecholamines?</h3>
These are the neurotransmitters that have a catechol and a side chain that is an amine.
<h3>Which catecholamines are released by the sympathetic nervous system?</h3>
Epinephrine and norepinephrine are the catecholamines that are released by the sympathetic nervous system to increase the heart rate.
<h3>Where are these hormones released?</h3>
These hormones are released in the blood.
<h3>How does this hormone increase the heart rate?</h3>
- "These hormones are released at the neuromuscular junction of the cardiac nerves."
- "They shorten the repolarization period."
- This speeds up the rate of depolarization and contraction and thus the heart rate is increased.
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<h2>Mesophyll cells</h2>
Explanation:
The most distinctive characteristic of leaf mesophyll cells is that they are filled with many chloroplasts
Mesophyll cells constitute the main body of a leaf, occurring between upper and lower epidermis
Typically, the leaves of temperate-zone plants have two layers of mesophyll cells, the palisade mesophyll on the upper side and the spongy mesophyll on the lower side
The palisade mesophyll is a layer of densely packed, columnar cells which contain many chloroplasts, this layer is responsible for most of the photosynthesis of leaves
The spongy mesophyll is composed of large, often odd-shaped, photosynthetic cells separated from one another by large, intercellular spaces, these intercellular spaces apparently facilitate the exchange of photosynthetic gases
The statements that describe steps taking place in the nitrogen cycle are
- Many biotic and abiotic factors play a role in recycling nitrogen ( A )
- Farming practices and chemicals lead to a build-up of nitrates in the soil ( E )
Nitrogen cycle is biochemical process whereby nitrogen is converted to various chemical forms as it passes through the atmosphere, Marine and terrestrial ecosystems .
Nitrogen cycle undergoes four ( 4 ) important processes which are :
- Fixation
- Ammonification
- Nitrification and
- Denitrification
Hence we can conclude that The statements that describe steps taking place in the nitrogen cycle are :
Many biotic and abiotic factors play a role in recycling nitrogen and
Farming practices and chemicals lead to a build-up of nitrates in the soil
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