The correct answer is option A, that is, Phylum Porifera.
The species of Phylum Porifera are aquatic, that is, mostly marine. They exhibit cellular grade of the body, they are diploblastic animals with asymmetrical symmetry. They lack body cavity and exhibits a holozoic mode of nutrition with intracellular digestion.
They lack circulatory and nervous system and possess the tendency to regenerate their parts of the body. The organisms in phylum Porifera exhibits both asexual and sexual mode of reproduction.
Answer:
C. cannot be larger than its fundamental niche
The atomic number of protactinium is 91
The discovery of that genes can be inserted or tiedinto an other dna molecule using a ligase enzyme
Answer:
The events in chronological order are:
- Abrin is absorbed into the blood and enters the body's cells
- Abrin binds to ribosomes in the cytoplasm
- Abrin inactivates the 28S rRNA in the large subunit of the ribosome.
- Ribosomes are unable to add new amino acids to polypeptides
- Protein synthesis halts in many tissues
- Multiple organ systems fail
- Victim dies
Explanation:
Abrin is a toxic protein obtained from the seeds of Abrus precatorius, it is highly toxic, with an estimated human fatal dose of 0.1-1 microgram/kg, and causes death after accidental and intentional poisoning.
When ingested the abrin would enter the victim's body and travel through the blood and eventually enter a cell's cytoplasm (abrin is absorbed into the blood and enters the body's cells). Once there it would interact with the ribosomes and reacts with them on a molecular level (peptide bond catalytic enzyme) (abrin binds to ribosomes in the cytoplasm), which results in the ribosome exhibiting its toxic response to abrin (abrin inactivates the 28S rRNA in the large subunit of the ribosome). As a result of the ribosome reacting to abrin (ribosomes are unable to add new amino acids to polypeptides), protein synthesis within that cell is affected (protein synthesis halts in many tissues). Once multiple cells are affected by abrin the organ will exhibit its toxic response (multiple organ systems fail), and the victim would die.
