Answer:
a. eukaryotes
b. unicellular
c. autotrophs; heterotrophs
Explanation:
Protists represent a separate kingdom of eukaryotic organisms (ie., organisms whose cells have a nucleus). The most important features of protists include: 1- they are unicellular organisms, 2-contain mitochondria, 3-can be parasites, and 4-generally live in optimal conditions in moist or aquatic environments. In the past, protists were divided into Protozoa (animal-like organisms) and Protophyta (plant-like organisms), which nowadays we know are heterotrophic (also often parasitic) and photosynthetic protists, respectively.
Answer:
recombinant DNA
Explanation:
In molecular biology, recombinant DNA molecules are genetic sequences formed by combining DNA material from different sources (i.e., organisms, populations, species, etc). Proteins produced from DNA recombinant molecules are known as recombinant proteins. Molecular cloning is the most widely used technique in molecular biology in order to produce recombinant DNA molecules. In this technique, a cloning vector such as, for example, a plasmid of a bacterium, is used to insert a foreign DNA fragment into another cell which is then expressed in the host cell.
Answer: I would say D)
Explanation:Phytoplankton are the autotrophic components of the plankton community and a key part of oceans, seas and freshwater basin ecosystems. This is the least ddt and is concentrated.
Answer: due to insufficient exocytosis in the type II alveolar cells
Striated muscles contain repeating sarcomeres of overlapping arrays of long, thin actin and thicker myosin filaments. Myosin filaments contains the myosin heads, which are enzymes that can bind to actin, split and make use of the energy from ATP. When muscle contraction starts, myosin heads bind to actin, change their configuration on actin, liberating the products of ATP hydrolysis and causing slide of the actin and myosin filaments. The action of the proteins troponin and tropomyosin on the actin filaments regulates vertebrae striated muscle contraction. The release of calcium ions from the sarcoplasmic reticulum is triggered by the nervous stimulation which causes depolarization of muscle membrane. Calcium ions bind to troponin and thus cause or allow the tropomyosin strands on the actin filament to move so that the part of the actin surface where myosin heads need to bind is uncovered. Contraction then occurs and only stops when the sarcoplasmic reticulum pumps calcium out of the muscle interior.
So basically, what triggers the uncovering of the myosin binding site on actin is the calcium ions binding to troponin and changing configuration.
