Answer:
A) The striations are due to the orderly arrangement of actin and myosin
Explanation:
Smooth muscles are non-striated involuntary muscles which are found in the walls of stomach, urinary bladder, blood vessels...Smooth muscle tissue is composed of spindle-shaped muscle cells with single central nucleus. Like the other two type of muscles (cardiac and skeletal), smooth muscles also have four main functions:
- Contractility-ability to contract. In the case of skeletal muscles it is voluntary, while in cardiac and smooth muscles it is unconscious.
- Excitability-ability to change membrane potential usually by the influence of nervous impulse.
- Extensibility-the capacity to lengthen
- Elasticity-ability to change its length and then return to previous.
Answer:
There are several reasons that say that scientific understandings can can change over time:
- The development of new techniques for observing investigations can bring new ways of thinking and understandings related to science.
- New science observations can be affected by political, social, or religious convictions.
- Change in the process of observation can completely change the scientific understandings over time.
Answer: 200metres per second
Explanation:
The wavespeed of a wave is the distance covered by the wave in one second. It is measured in metre per second, and represented by the symbol V.
Recall that Velocity (V) = Frequency F x wavelength λ
V = F λ
In this case, wavelength (λ)= 20 m frequency = 10 Hz.
Hence, V = F λ
= 20 metres x 10 hertz
= 200 metres per second
Thus, the wave travels at a speed of 200 metres per second
