<span>Stimulation of thoracic or lumbar spinal regions; impulse reaches chain ganglion; acetylcholine release</span>. Acetylcholine is released if the synapse happens in the sympathetic ganglion, if the synapse is in post-ganglionic neuron, norepinephrine is released.
Innate: keratinized epithelium
stratified squamous epithelium hypodermal areolar connective tissue antigen presenting cells major histocompatibility complexes complement (antibody -dependent pathway )
Innate or non-specific response is the first defense against invaders. Components of this response include physical (e.g. skin . mucosa) and chemical barriers against pathogens and cells such as Natural Killer cells, macrophages, neutrophils, dendritic cells, mast cells, basophils, eosinophils. Innate response reacts immediately.
Adaptive: immunoglobulin plasma cells agglutinin
helper t cells memory t cells cytotoxic t cells cd4+cells
t lymphocytes
Adaptive immune response or specific response is specific to the pathogen presented and mediated by lymphocytes, B and T cells. Adaptive immune response creates immunological memory after the first, initial l response to a specific pathogen which leads to enhanced response.
Answer:
The effort put by scientist and sailors about earth is that they keep on going round the earth and putting their lives in danger and some even give their lives.
Explanation:
......
Answer: Survival rate up to start of April = 76.67%
Explanation: size of colony = 150mice.
Size of colony in February =125mice.
Size of colony in march = 115 mice.
1. Survivorship rate in February
= Size of colony / size in February *100.
= 122 / 150 * 100
= 83.33% to the nearest hundredth
2. Survivorship rate in march
= Size of colony / size in march *100.
= 115/150 * 100
= 76.67% to the nearest hundredth.
Answer:
The answer is B. Some organic molecules, including amino acids, could have been produced from chemical reactions on early Earth.
Explanation:
Miller-Urey Experiment:
The Miller-Urey experiment was an attempt to explain the origin of life on Earth. Miller-Urey simulated the primordial soup i.e. the environment of primitive Earth to prove the spontaneous generation of organic molecules. The conditions they introduced included:
- A methane-ammonia-hydrogen and water mixture that exactly simulated the primordial soup.
- A spark of 70,000 volts that simulated lightening.
- A temperature of 800 degree Celsius.
Observations:
- After running for 18 days, the final solution was examined for presence of organic molecules.
- Miller-Urey observed that most of the methane and ammonia had been consumed and the mixture contained carbon monoxide and nitrogen.
- The solution further contained 25 amino acids (mainly, glycine, alanine and aspartic acid)
, several fatty acids
, hydroxy acids and amide products.
The experiment concluded that simple organic compounds such as amino acids could have been formed through spontaneous generation under the Earth's primitive environmental conditions.
