1 picture which picture shows how an organism uses parental care to ensure the continuation of its species ?
Answer:
DNA may be taken up by bacterial cells and be active.
Explanation:
To understand Avery, MacLeod, and McCarty's experiment, it is important to know Frederick Griffith's precursor experiment. The microbiologist worked at the British Ministry of Health's Pathology Laboratory with pneumococci (commonly known as the bacterium Streptococcus pneumoniae, then known as Pneumococcus, which causes pneumonia), which were previously classified into several types. When cultured in petri dishes in the laboratory, the pneumococci that synthesize their capsules generate 'smooth' colonies. Subcutaneous injection of liquid culture of these pneumococci into mice causes their death. However, in vitro culture also allows the emergence of rough colonies', whose bacteria have lost the ability to synthesize mucopolysaccharide (and therefore have no capsules). Rough mutants could no longer be classified with sera and, moreover, lost their virulence: mice inoculated with them remained alive, unlike inoculated with smooth pneumococci.
The nature of Griffith's transforming principle remained unclear until the work of Avery, MacLeod, and McCarty. They repeated the in vitro transformation of pneumococci at the Rockfeller Institute for Medical Research, but replaced heat-dead cells with a purified fraction of smooth bacterial extract (unable to cause disease alone) and treated the material with different enzymes, each capable of destroying a specific type of macromolecule. Experience has shown that this fraction retained its transforming capacity when treated with protein or RNA degrading enzymes, but lost that ability when treated with DNA degrading enzymes. These results indicated that the chemical nature of the 'transforming principle' was DNA.
Thus, we can conclude that in addition to identifying genetic material, Avery, MacLeod and McCarty experiments with different strains of Streptococcus pneumoniae demonstrated that DNA can be absorbed by bacterial cells and be active.
Answer:
a. Gametophytes of bryophytes
d. Sporophytes of seedless vascular plants
Explanation:
Bryophytes are non-vascular plants. The plant body is haploid gametophyte which is its dominant phase and bears sex organs. The gametophyte may be leafy as in moss and may be with thalloid as in liverworts.
Pteridophytes are seedless, true vascular plants. The plant body is the diploid sporophyte. The sporophyte is differentiated into true leaves, stem and roots.
Answer:
Rapid eye movement sleep (REM) may be defined as the the phase of the sleep that are unique to the mammals. This sleep is marked by the muscle tone.
The REM leads to the increase in pressure with deprivation. This leads to the increase in the rapid eye movement and plays an important role in the REM sleep and dreaming of the individual and quite necessary in the adult.
"Hippocampus" is the one part of the central nervous system among the following choices given in the question that helps students remember the correct answers to the questions on these exams. The correct option among all the options that are given in the question is the second option or option "B".
