I believe that phytoplankton is necessary to begin a food web
Answer:
C. Go through a step called metaphase.
Explanation:
In plant and animal cells metaphase is a step they both share.
Answer: Alexandrium catenella is a species of dinoflagellates. Alexandrium has two flagella that enable it to swim. While one flagellum encircles the cell causing the cell to rotate and move forward, the other extends behind the cell and controls the direction.
The cell wall is composed of cellulose Theca.
Length 20 - 48 μm, width 18 - 34 μm
Yellow-green to orange-brown
Forms chains of 2, 4 or 8 cells
Antigens; they are molecules that are foreign to the body, thus stimulating a response by the b- and t-cells that aim to defend the body against harmful and mostly foreign bacteria.
Answer:
1. Acetylcholine binds to receptors on the motor end plate
2. Ligand-gated channels open leading to depolarization
3. End plate potential triggers an action potential
4. Transverse tubules convey action potentials into the interior of the muscle fiber
5. Calcium is released from the sarcoplasmic reticulum
6. Calcium ions bind to troponin, which then moves tropomyosin
Explanation:
Acetylcholine (ACh) is a signaling molecule (neurotransmitter) that binds to receptors on muscle cells. This binding triggers the opening of ligand-gated sodium channels, thereby ions enter into muscle cells, which causes the depolarization of the sarcolemma and thus promotes the release of Ca2+ ions from the sarcoplasmic reticulum. The myoneural junction, also known as the motor endplate, is the site of synaptic contact between a motor axon and a skeletal muscle fiber. The endplate potential is the voltage that produces the depolarization of muscle fibers when ACh molecules bind to their receptors in the cell membrane. This depolarization spreads in the sarcolemma through transverse tubules (T tubules) and thus generates an action potential. Finally, this action potential induces the release of Ca2+ in the sarcoplasmic reticulum, which activates troponin protein and induces muscle contraction.
