Answer:
where is the file attachment?
prophase
Further genetic variation comes from crossing over, which may occur during prophase I of meiosis. In prophase I of meiosis, the replicated homologous pair of chromosomes comes together in the process called synapsis, and sections of the chromosomes are exchanged.
Hope it helps!
Answer:
Plasma membrane is the semi-permeable membrane that allow the movement of some selected particles only against the concentration gradient or along the concentration gradient.
Different substances can be move through the diffusion, active process and passive process. The hydrogen in the vesicle has been moved through the facilitated diffusion. In this process, the hydrogen ions will move along the concentration gradient without the requirement of energy but requires the channel protein for its transport.
Answer:
It is essentially a broth culture filtrate of the penicillium mould.
Explanation:
- Alexander Fleming invented penicillin an antibiotic in 1928. These have been rated as the most important scientific discovery, being among the first antibiotics to be effective against bacterial infection.
- Penicillin belongs to different families that are selective against a large variety of bacteria.
- In fact, this antibiotic was discovered by fleming and accident in which he left a platter containing staphylococci open and was contaminated by green mould. There was an area of inhibited bacterial growth around the mould from which he inferred that the mould produced a material that inhibited bacterial growth. This was found to be a penicillium mould through further study.
- I assume penicillin is the most significant discovery so far because it was the first antibiotic ever discovered against bacterial infection in the absence of any drug.
