PART 1
1. The answer is low frequency electromagnetic waves are able to go around obstacles due to their larger wavelengths. This characteristic of lower frequency waves is due to their ability to diffract around obstacles such as buildings and hills. Therefore, they transmit over long distances unlike high frequency electromagnetic waves.
2. One disadvantage is interference. Electromagnetic waves of the same frequency transmitted at the same time will interfere with one other and therefore the signal will be lost or scrambled. Other electromagnetic waves such as microwaves are affected (interfered with) by weather elements.
3. Analogue signals are continuous signals with wave-like properties while digital signals are discrete signals or pulse (ons (1s) and offs (0s) that represent bits). Analogue signal is represented by a sine-wave while digital signal is represented by discrete squares waves.
4. Digital signals are less immune to eavesdropping unlike analogue signals. Analogue signal is also more prone to distortion unlike digital signal. Digital signals transmit more data than analogue signals. Digital signal draw less energy to transmit compared to analogue signal.
5. Broadcasting of TV is nowadays using digital signals due to the high number of available channels. Computers and the interne utilize digital signaling to transmit data. Controls systems such as radar system also use aspects of analogue waves. Sensors also utilize analogue waves especially transducers such as seismology equipment.
PART 2
1. One way is by sending radio waves to probes sent out in space to give them commands during exploration. Radio telescopes also pick up naturally-occurring radio waves from space and analyze the data to make conclusions about space and the astronomical objects.
2. Radio waves are used in communication by transmitting data over long distances. One example is its use TV transmission. Another is through military defense of airspace. The radio waves are used to detect enemy intrusion into restricted airspaces using radar.
3. It is common that signal from the environment will be in analogue signal format. The conversion to digital signals allows for the digital equipment in the telescope to interpret and analyze the data. Telescopes prefer digital equipment because they consume less power, handle more data, and are less prone to intrusion, and distortion, hence more secure to analogue equipment.
Answer:
One band of light density and one band of heavy density.
Explanation:
According to conservative model of replication, the original strands do not separate from each other during replication. Hence, after replication the old strands are together and the new strands are together.
Here, cells were grown in 14N medium first so 14N was used for DNA replication and all DNA molecules had 14N. When the cells were transferred to 15N medium, only 15N was available for replication process. New DNA molecules would be synthesised using 15N (15N15N) and old DNA molecules have 14N (14N14N). Hence, in density gradient one band will be of light density (14N14N) and one band will be of heavy density (15N15N).
Answer:
Muscle tissue is categorized into three different types: skeletal, cardiac, and smooth. Each type of muscle tissue in the human body has a unique structure and a specific function. Skeletal muscle moves bones and other structures. The heart muscle contracts the heart to pump blood.
Sympathetic division and the parasympathetic division
The another are differentiated from the anamniotes by the presence of their terrestrially adapted eggs. These eggs are protected by amniotic membranes. Development of these membranes have provided another with their own aquatic environment needed for development.
The development of amniotic membrane is a characteric of amniotic eggs. These membranes include: chorion' facilitating the exchange of gases between the embryo and the mother; amnion, protection the embryo from injuries and shock and also aiding hydration; allantois, excretion of nitrogenous waste such as urea and uric acid etc and also help in respiration.
Another characteristics is waterproof skin due to the presence of lipids.
Another is the existence of costal rib ventilation of the lungs: enables of loss of CO2 through the lungs rather than buccal pumping as foumd in anamniotes.
