Answer:
A. chemical substance whose atoms all have the same number of protons
Explanation:
An element is a substance which contains identical atoms that have the same number of protons in the nucleus.
Elements are arranged in the periodic table according to their atomic number (= number of protons): so atoms of different elements have a different number of protons in their nuclei.
For a neutral atom, the number of electrons around the nucleus is also equal to the number of protons.
Moreover, atoms of the same element can have a different number of neutrons, despite having the same number of protons - these atoms are called isotopes.
Answer:
47 m
Explanation:
Data obtained from the question include the following:
Length of dry leg 1 (L1) = 40 m
Length of dry leg 2 (L2) = 25 m
Length of swimming course (L) =..?
The length of the swimming course can be obtained by using pythagoras theory as shown below:
L² = L1² + L2²
L² = 40² + 25²
L² = 1600 + 625
L² = 2225
Take the square root of both side.
L = √2225
L = 47.1 ≈ 47 m
Therefore, the length of the swimming course is approximately 47 m.
Answer:
The upper motor neurons synapse in the spinal cord connect with anterior horn cells of lower motor neurons, usually via interneurons. The anterior horn cells are the cell bodies of the lower motor neurons and are located in the grey matter of the spinal cord.
Explanation:
Interneurons are the central nodes of neural circuits, enabling communication between the upper motor neurons, sensory or motor neurons located in the brain and spinal cord and they send signals to lower motor neurons or central nervous system (CNS) in the brain stem and spinal cord . When they get a signal from the upper motor neurons, they send another signal to your muscles to make them contract. They play vital roles in reflexes, neuronal oscillations, and neurogenesis in the adult mammalian brain.
Renshaw cells are among the very first identified interneurons. They are excited by the axon collaterals of the motor neurons. In addition, Renshaw cells make inhibitory connections to several groups of motor neurons.