Answer:
Correct answer is D.
Explanation:
Silent mutations have no observable effect while neutral mutations does not cause harm or benefit the organism in any way. Missense mutations are single nucleotide changes that only affect one codon and one protein. In this case answer is frameshift mutation because this type of mutation is result of DNA insertion or deletion which changes the way DNA sequence is read and may affect more than one gene.
It is known as acetabularia acetabulum. An algae that you see in water mostly, its like those mini "lily pads" you pull up from the water. :)
Answer: analysis the similarities and differences between organisms of the same species
Explanation:
Comparative morphology is analysis of the patterns of the locus of structures within the body plan of an organism, and forms the basis of taxonomical categorization. Functional morphology is the study of the relationship between the structure and function of morphological features.
I believe the correct order is:
D - A nerve signal arrives at an axon terminal;
B - Voltage gated calcium channels open and calcium enters the cell;
C - ACh is released and diffuses across the axon terminal;
E - Ligand gated sodium channels open and sodium enters the cell.
A - A postsynaptic potential is produced;
Explanation:
The dendrites of the presynaptic neurons receive a signal. The signal stimulates the nucleus of the presynaptic neuron to produce an electrical signal that is managed by the axon hillock. the axon hillock again manages and transmits the nerve impulse into the axon towards the axon terminal. The signal is transmitted via saltatory conduction on myelinated axons for faster communication. When the nerve impulse reaches the axon terminal, it causes opening of voltage gated calcium ion channels. This will cause an influx of calcium ions into the presynaptic axon terminal. The influx of calcium ions then stimulates the synaptic vessicles in the presynaptic membrane that contain the neurotransmitter acetylcholine (ACh) to move towards the presynaptic membrane. They then fuse with the membrane and open up releasing all their acetylcholine into the synaptic cleft (space between presynaptic membrane and post synaptic membrane). The ACh will bind to ligand ion channels on post synaptic membrane causing opening of sodium channels and there is an influx of sodium inside the post synaptic membrane producing a membrane potential. The voltage gated calcium ion channels in the presynaptic membrane will then close and no more ACh is released. The cells then return to rest. The acetylcholine in the postsynaptic neuron is either broken down by the enzyme acetylcholinesterase into metabolites that are used by the cell or they are removed as waste into the surrounding glial cells called astrocytes that nourish neurons. They (ACh) also can be stored for future use by the post synaptic neuron.
Level: High School
Subject: Biology
Topic: The nervous system
Atrioventricular Canal Defect is an abnormality that causes the mixing of blood.The condition occurs when there's a hole between the heart's chambers and problems with the valves that regulate blood flow in the heart. Sometimes called endocardial cushion defect oratrioventricular septal defect, atrioventricular canal defect is present at birth (congenital).
