Answer:
The correct answer would be B) the flow of water through the body of a sponge.
Sponges are multi-cellular organisms which are devoid of organ systems like digestive system, nervous system, circulatory system et cetera.
They have a unique feeding system in which they keep constant water flow through their bodies. They obtain food and oxygen and remove waste through this water movement.
The movement of water throughout the sponge is unidirectional in nature. It enters the sponge body through ostia and exit from the osculum.
As the water is pumped out, the cells present in the walls filter out the food present in the water.
A. Correct. RNA means Ribonucleic acid.
b. Correct. RNA contains uracil instead of thymine. DNA doesn't contain uracil but thymine.
c. Incorrect. RNA is single stranded.
d. Correct. Plus, DNA contains deoxyribose.
Answer:
uhhhhhhh erm have a good day is the answer yep mhm
Explanation:
A transcriptional activator is a protein (transcription factor) that increases transcription of a gene or set of genes. Activators are considered to have positive control over gene expression, as they function to promote gene transcription and, in some cases, are required for the transcription of genes to occur. Most activators are DNA-binding proteins that bind to enhancers or promoter-proximal elements.The DNA site bound by the activator is referred to as an "activator-binding site". The part of the activator that makes protein–protein interactions with the general transcription machinery is referred to as an "activating region" or "activation domain".
Most activators function by binding sequence-specifically to a regulatory DNA site located near a promoter and making protein–protein interactions with the general transcription machinery (RNA polymerase and general transcription factors), thereby facilitating the binding of the general transcription machinery to the promoter.Other activators help promote gene transcription by triggering RNA polymerase to release from the promoter and proceed along the DNA. At times, RNA polymerase can pause shortly after leaving the promoter; activators also function to allow these “stalled” RNA polymerases to continue transcription.
The activity of activators can be regulated. Some activators have an allosteric site and can only function when a certain molecule binds to this site, essentially turning the activator on Post-translational modifications to activators can also regulate activity, increasing or decreasing activity depending on the type of modification and activator being modified.
In some cells, usually eukaryotes, multiple activators can bind to the binding-site; these activators tend to bind cooperatively and interact synergistically.
No because of water evaporates and the cumebous and unbous layers take in the vapperation of the water that humans use and other plants and animals. so no
Answer:
Regulation, Control, Coordination, Growth, Nutrient, Nutrition, Homeotasis