<span>Cocaine is an indirect agonist of dopamine <span>receptors which</span> means he </span>has no specific agonist activity at the dopamine receptor<span> but he enhances his activity. Cocaine</span> acts by binding to the dopamine transporter, blocking the removal of dopamine from the synapse and blocking termination of dopamine signalling. As a result, it increases the extracellular concentration of dopamine and therefore signal to the receiving neurons is amplified.
ANSWER:
Cytokines, Chemokines, Leukocytes, Neutrophils, Macrophages, and Dendritic cells are all involved
EXPLANATION:
On the incidence of Streptococcus, the immune system activates a complex response that relies basically on the instatement and activation of macrophages, neutrophils, and dendritic cells.
These activities will only occur on the activation of innate immune responses through workout between pattern recognition receptors (PRRs) with streptococcus derived pathogen-associated molecular patterns (PAMPs).
Moreso, cytokines and chemokines (well known are IL-1β and CXCL1 respectively) produced by macrophages and dendritic cells on exposure to Streptococcus, elicits neutrophil.
Neutrophils then produces antimicrobial proteins, reactive oxygen species (ROS) and sometimes neutrophil extracellular traps (NETs), all these for the bacterial infection control.
Answer:
RBCs' production is controlled by erythropoietin.
Mature RBCs are released into the bloodstream after approximately seven days RBCs are produced in the bone marrow
Explanation:
The hormone erythropoietin is produced and released in the bloodstream by peritubular interstitial cells of kidneys. The function of erythropoietin is to increase the number of the precursors of red blood cells and thereby to stimulate the production of red blood cells in the bone marrow. When the oxygen supply to body cells is reduced, the hormone erythropoietin stimulates the development of proerythroblasts into reticulocytes and thereby increases the RBC production.
RBCs are produced by the process of erythropoiesis and take about seven days to become mature and to be released in circulation to serve the function of oxygen delivery. The maturation of RBCs also includes the loss of most of the organelles such as the nucleus and mitochondria to accommodate hemoglobin protein. The life span of circulating RBCs is about 100-120 days.
Mitosis simply refers to cell division in which one cell divides and produce two new cells that are identical.
Here are the steps:
(1) Prophase
<span>(a) Early prophase when cells starts to break down some structures and build others up. It sets up the stage when the chromosome is dividing.</span><span>(b) Prometaphase, mitotic spindle begins to capture and organize the chromosomes.
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(2) Metaphase
<span>The spindle has captured all the chromosomes. They lined them up at the middle of the cell making it ready for division.
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(3) Anaphase
<span>The sister chromatids separate from each other and are pulled towards opposite ends of the cell.
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(4) Telophase
<span>The cell is nearly finished dividing, and it starts to re-establish normal internal structures as cytokinesis takes place.</span>
Answer:
A. If the aerobic pathway—cellular respiration—cannot meet the energy demand, then the anaerobic pathway—lactic acid fermentation—starts up, resulting in lactic acid buildup and "oxygen debt."
C. After about 90 seconds of intense exercise, the muscles become depleted of oxygen, and anaerobic respiration can no longer function to produce ATP, resulting in "oxygen debt."
Explanation:
There are two sources of carbohydrates in the human's body for energy (ATP) production. 1) Creatine phosphate and 2) Glycogen. Creatine phosphate metabolizes easily and yields ATP quickly. Whereas glycogen is stored form of carbohydrate which yields energy more slowly. Therefore, initially, our bodies use creatine phosphate and then shift to glycogen. Within 60-90 seconds, the creatinine phosphate in the body is mostly utilized and then energy is produced by the use of glycogen in aerobic pathway. During areobic pathway, oxygen supply is sufficient and per cycle, it produces 32 molecules of ATP. However, when oxygen supply is limited or absent, the body will metabolize glycogen to lactic acid via fermentation and produce only 2 molecules of ATP.
Now consider the example: Kenny hikes all day at a steady pace therefore the supply of oxygen is sufficient for aerobic cellular respiration for ATP production. In this scenario, the oxygen debt is minimal and Kenny relies on aerobic respiration pathway to obtain energy. On the other hand, Janelle runs fast (100 meters in 13.5 seconds) and her cellular respiration would be on the compense of aerobic pathway initially which will be shifted to anaerobic pathway after the supply of oxygen is reduced/minimum. Janelle will heavily rely on the anaerobic pathway because running fast needs energy which cannot be provided via aerobic pathway easily. Therefore, Janelle's body will produce lactic acid and suffer from oxygen debt.
