Stellar evolution is the process by which a star undergoes a sequence of radical changes during its lifetime. Depending on the mass of the star, this lifetime ranges from only a few million years (for the most massive) to trillions of years (for the less massive), considerably more than the age of the universe. ^
Small, relatively cold, low mass red dwarfs burn hydrogen slowly and will burn for hundreds of billions of years
Massive hot supergiants will live for just a few million years.
A mid-sized star like the Sun will remain on the main sequence for about 10 billion years. Hope tis helps!!
Answer:Thirty years ago, 45 out of 200 individuals, or 22.5% of individuals, were at least 1.2 meters tall. Presently, 50.5% of individuals are at least 1.2 meters tall. Meanwhile, individuals below 1.2 meters in height have decreased significantly between the two years of data. This data supports the argument that directional selection is occurring.
Explanation:
Answer:
smooth endoplasmic reticulum
Explanation:
Smooth endoplasmic reticulum differs from the rough endoplasmic reticulum in not having ribosomes on its surface. The smooth endoplasmic reticulum (SER) extends from the rough ER and forms a network of membrane tubules. The function of the smooth ER is to serve as a site for the synthesis of lipids, fatty acids, and steroids such as estrogens and testosterone.
Enzymes for the synthesis of these diverse biomolecules are present in smooth ER. The smooth ER present in the muscle cells is called the sarcoplasmic reticulum. It stores the calcium ions which are released into the sarcoplasm of muscle cells during muscle contraction.
Answer:
$220
Explanation:
For Mowing:
Revenue: $1,200
Additional cost: $(100)
Transportation cost : $(50)
Net Income : $1050
For Painting:
Revenue: $1,400
Additional cost: $(80)
Transportation cost : $(50)
Net Income : $1270
Incremental Net income = $1270 - $1050
= $220
Answer:
Option D
Explanation:
Cyanobacteria preserve its photosynthetic pigments in the thylakoids which allows masking of green of chlorophyll a and other accessory pigment i.e phycobiliproteins (phycocyanin, allophycocyanin and phycoerythrin).
Chlorophyll a is mainly responsible for harvesting light for photosynthesis. Phycocyanin is blue in color, allophycocyanin is blue in color and phycoerythrine is red in color. These together harvest light in the green, yellow and orange part of the spectrum which cannot be used by other phytoplankton species
Hence, option D is correct
