Answer:
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.
1. Nucleus step1: DNA is transcribed into mRNA
2. Ribosome step2: mRNA is translated into protein
3. Endoplasmic Reticulum step 3: Newly synthesised proteins are transported.
4. Golgi apparatus Step 4: Proteins are modified then transported away
In Golgi body or apparatus, the proteins are modified, sorted and packaging occurs for secretion.
Commensalism is when one organism benefits off the other one without harming it. Examples are tree frogs that use plants for protection or jackals that have been expelled from packs trailing tigers and feeding on the remains of its kill. Barnacles on whales get shelter by attaching to a whales body
The correct answer is: A checkpoint will be activated if the spindle does not attach to a kinetochore.
Prokaryotes, do not undergo mitosis (like eukaryotes) and therefore have no need for a mitotic spindle. Prokaryotes also don’ t have checkpoints foor the regulation of cell division.
Normal eukaryotic cells (unlike cancer cells), move through the cell cycle in a regulated way in order to make sure that cells don't divide under conditions that are unfavorable for them. Information about their own internal state (nutrients, signal molecules, DNA integrity) is signal to go or not to go through the cell division. Because of that there are few checkpoints in the cell cycle at which the cell examines the signals and makes a “decision”. The major checkpoints are:
• The G1- the first point at which it must choose, once it passes the G1 checkpoint the cell enters S phase
• The G2-the cell checks DNA integrity and checks if replication is done well.
• The spindle checkpoint-at the transition from metaphase to anaphase.
