Carbon dioxide—\text {CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript—from the atmosphere is taken up by photosynthetic organisms and used to make organic molecules, which travel through food chains. In the end, the carbon atoms are released as \text {CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript in respiration.
Slow geological processes, including the formation of sedimentary rock and fossil fuels, contribute to the carbon cycle over long timescales.
Some human activities, such as burning of fossil fuels and deforestation, increase atmospheric \text{CO}_2CO
2
start text, C, O, end text, start subscript, 2, end subscript and affect Earth's climate and oceans.
A. It has organelles enclosed in membranes
Okay so, the mitochondria are shaped perfectly to maximize their productivity. They are made of two membranes. The outer membrane covers the organelle and contains it like a skin. The inner membrane folds over many times and creates layered structures called cristae. The fluid contained in the mitochondria is called the matrix. The folding of the inner membrane increases the surface area inside the organelle. Since many of the chemical reactions happen on the inner membrane, the increased surface area creates more space for reactions to occur.
Hope that helps (:
Answer:
b- It is a spontaneous process.
Explanation:
Passive transport is the type of transport of substances across the plasma membrane that occurs without energy expenditure and occurs spontaneously. There is no energy expenditure during passive transport because substances naturally move from the more concentrated to the less concentrated medium, ie in favor of the concentration gradient.
Substance transport occurs until concentrations inside and outside the cell are equalized.
According to this conceptualization we can conclude that the correct answer to your question is the letter B.
People with HIV are unable to fight off these rare diseases because they have a weakened immune system.
