The correct answer is A. Nebula, star of seven stellar masses, a red supergiant, supernova, black hole.
Explanation
Stars have a life cycle that begins with the gravitational collapse of a gaseous nebula. Subsequently, thermonuclear fusion occurs that allows the conversion of hydrogen into helium, this causes the released energy to pass through the star and radiate in a phase called the star of seven stellar masses. After several billion years, the star passes to the "red giant" stage. Here the star contracts and raises its temperature. After this, the stars (which have masses greater than the sun) detach from their layers forming supernovae, and later, these give rise to "black holes". According to the above, the correct answer is A. Nebula, star of seven stellar masses, a red supergiant, supernova, black hole.
Answer: All the above options are correct about the characteristics of Lumbriculus variegatus.
Explanation:
Lumbriculus variegatus also called the black worm belongs to the phylum Annelida and is used by biologists to illustrate:
-blood vessel pulsations,
-swimming reflex,
-peristaltic crawling behavior,
-giant nerve fiber action potentials.
These studies where carried out on them due to the characteristics they possess. These includes:
-its blood circulates in a closed circulatory system
-Freshwater worm found throughout North America and Europe
-Prefers the shallow habitats found at the edges of ponds, lakes, or marshes
-Feeds on decaying vegetation and microorganisms.
Answer:
<em>Bracketed and indented keys are two dichotomous/or branching keys with an ordered, numbered couplet, and spatially differentiated respectively.</em>
Explanation:
Dichotomous keys are used in the identification and classification of taxa.
Bracketed keys, or parallel keys, are easy to understand- for efficiency, these keep the first two entries of every couplet or pair being compared. It also makes use of a numbering system in the couplet choices for easy tracking.
Indented keys maintain an equal distance from the margin on the left of the pages. Successive couplets are indented til the taxon is identified.
starts with sunlight and photosynthesis if you are talking about plants