• Matthias Schleiden observed that all plants were made of cells; Theodor Schwann observed that all animals were also made of cells; and Rudolf Virchow observed that cells only come from other cells.
• Prokaryotic cells- don’t contain a nucleus or any other membrane-bound organelle.
Eukaryotic cells- contain membrane-bound organelles, including a nucleus.
• Phospholipids make up the basic structure of a cell membrane and are arranged in a double layer called the lipid bilayer.
• Active Transport- moves ions from low concentration to high, using metabolic energy in the form of ATP.
Passive Transport - moves ions from high concentration to low, using no metabolic energy.
<span>The process which makes it possible is Differentiation.</span>
<span> G</span><span>estation means the process by which something develops.</span>
<span>Differentiation means the development from the one to many.</span>
Answer:
Ventilation is the movement of a volume of gas into and out of the lungs. Respiration is the exchange of oxygen and carbon dioxide across a membrane either in the lungs or at the cellular level.
Explanation:
Answer:
The natural level of ozone in the stratosphere is a result of a balance between sunlight that creates ozone and chemical reactions that destroy it.
Explanation:
Answer: b. dead at maturity and are used to transport sugars throughout the plant.
Phloem cells are the cells which transport the product of photosynthesis that is food from the leaves to other parts of the plant. A typical phloem consist of sieve cells, phloem fibers, and phloem parenchyma. Sieve cells are elongated and they have minute pores which facilitates the transport of food through these pores. The phloem fibers provides mechanical support to the phloem. Phloem parenchyma cells are responsible for the storage of food. The process by which phloem transport food is called as translocation. Sieve cells are the main type of cells helps in food translocation, in maturity these cells looses their nucleus and ribosomes therefore, they die in maturity.