Answer:
Radioactive labeling is a procedure used to monitor the path followed by a chemical element within a biological system to demonstrate the source.
Hypothesis:
The free oxygen produced during photosynthesis comes from water.
Procedure.
Single-celled algae were placed in four petri dishes containing carbon dioxide, glucose dissolved in Water.
In each box the oxygen was radioactively marked.
1 petri dish with CO2 marked. Experimental groups
2 petri dish with H2O marked. Experimental groups
3 petri dish with Glucose marked. Experimental groups (control)
4 petri dish with CO2 + H2O + Glucose, all marked. (control).
Answer:
Bacteria take DNA from their environment.
Explanation:
"Bacteria take DNA from their environment" is what best describes transformation in bacteria.
Answer:
According to the diagram, cell growth and preparation occur in steps 2 and 4, corresponding to phases G₁ and G₂ of cell cycle.
Explanation:
G₁ phase consists of the beginning of the cell cycle, following the process of previous division, and occurs in a cell that prepares for a next division. In this phase growth depends on the proliferation of mRNA to increase protein synthesis.
G₂ phase —third phase of the cycle— is the continuation of the process of cell growth induced by protein synthesis. Changes occur at the level of cellular components, as preparation of the cell prior to division.
I think you're talking about histones. Histones are proteins found in eukayotic cell nuclei. Histones are what DNA wrap around so it fits inside the nucleus and helps with the formation of chromosomes.
