Answer:Spectroscopy helps astronomers to determine the composition, temperature, density, and motion of an object.
Infrared spectroscopy helps to identify the atoms and molecules in the object.
The red shift or blue shift (Doppler Effect) in a spectral line tells how fast the object is receding from Earth or coming toward it.
The Doppler shift enables astronomers to discover extrasolar planets.
As a planet orbits its star, the star is alternately moving away from or toward us.
Astronomers can use the Doppler shifts to calculate the speed of the star and the mass of the planet that is tugging on it.
Explanation:
Answer:
DNA replication a process of copying of a cell's DNA. DNA replication is semiconservative process which means that each strand in the double helix helps in the synthesis of new, complementary strand and conserve the parent template.
The Molecular mechanism of DNA replication is as following:
- The double starnded DN in binded with hydrogen bond, the enzyme helicase opens up the DNA at the replication fork.
- A single stranded binding protein prevent the rewinding of DNA and so binds to the DNA around the replication fork
- Topoisomerase prevent supercoiling at replication fork.
- The ezymes primase come in action and produces RNA primers which are complementary to the DNA strand.
- DNA polymerase III help to extends the primers and allow them to add to the 3' end, to make new DNA.
- DNA Polymerase then remove RNA primers and replace with DNA.
- DNA ligase blocks the the gaps between DNA fragments.
So, this is the molecuar mechanism of DNA replication.
<u>Answer</u>: C) Hydrophobic interior, hydrophilic exterior
<u>Explanation</u>:
- The <em>plasma membrane</em> of the cell defines its boundary and separates its internal components from the external environment.
- The basic components of the plasma membrane include phospholipids, carbohydrates, proteins, and cholesterol.
- The plasma membrane is a phospholipid bilayer, with <em>hydrophobic</em> tails of the phospholipid projecting <em>inwards</em> and the <em>hydrophilic</em> exterior in contact with the external environment.
- <em>Due to this, the plasma membrane has a hydrophobic interior and hydrophilic exterior. </em>
The basis of classification of
Linnaeus’ system is sexual reproduction. The
only "natural" taxon in Linnaeus' system is the species. Species defined
as a population with viable, fertile reproduction are separated from
interbreeding with other species.
