Answer:
Summary
All cells have a plasma membrane, ribosomes, cytoplasm, and DNA.
Prokaryotic cells lack a nucleus and membrane-bound structures.
Eukaryotic cells have a nucleus and membrane-bound structures called organelles.
Explanation:
Eukaryotic Cells
Eukaryotic cells usually have multiple chromosomes, composed of DNA and protein. Some eukaryotic species have just a few chromosomes, others have close to 100 or more. These chromosomes are protected within the nucleus. In addition to a nucleus, eukaryotic cells include other membrane-bound structures called organelles. Organelles allow eukaryotic cells to be more specialized than prokaryotic cells. below are the organelles of eukaryotic cells , including the mitochondria, endoplasmic reticulum, and Golgi apparatus.
Prokaryotic cells are usually smaller and simpler than eukaryotic cells. They do not have a nucleus or other membrane-bound organelles. In prokaryotic cells, the DNA, or genetic material, forms a single large circle that coils up on itself. The DNA is located in the main part of the cell.
Answer: D.
The E. reticulum and Golgi bodies are concerned with secretion and synthesis of molecular substances e.g protein , lipids and steroid. Therefore these cellular organelles should contain Plasma B cells and Islets of Langerhans. for protein hormone synthesis(insulin) and antibodies production
Explanation:
Answer:
They sleep on just one side of their brain at a time
Explanation:
Dolphins are different from fishes that can breathe underwater.
It is necessary for them to get to the surface of the water at intervals to breathe air.
While sleeping, dolphins allows one hemisphere of their brains fall asleep while the other half is fully conscious. This means that If the left brain is sleeping, the right eye stays open and if the right brain is sleeping, the left eye stays open.
This happens so they always know when it's time to surface and breathe and when to escape when there is trouble.
Answer: prokaryotes (single celled micro-organisms/microbes)
Explanation: The first living things on Earth, single-celled micro-organisms or microbes lacking a cell nucleus or cell membrane known as prokaryotes, seem to have first appeared on Earth almost four billion years ago, just a few hundred million years after the formation of the Earth itself.
All DNA is remarkably similar, but some more than others. Humans' DNA would be closer to other mammals' than it is to, say, a bird. Using DNA shows how varied an animal really is from another. Specific parts of the DNA code for different things, so you might see a similar structure for wings and flippers.
