Answer:
Secretion of the neurotransmitter serotonin, which is a water-soluble amine molecule
Explanation:
Exocytosis is defined as the process where cell transports secretary products which are packaged in transport vesicles such as antibodies, peptide hormones, secretory proteins, and enzymes with the help of cytoplasm to the plasma membrane.
Some example of exocytosis are:
1) Neurotransmitters secrets from nerve cells.
2) Antigens which helps to stimulate the immune response.
3) Proteins of the plasma membrane.
Answer:
Answer is C.
Explanation:
A. The vessel length is pretty much constant. The body can't length or shorten blood vessels.
B. Blood viscosity is also fairly constant because the composition of blood cannot change quickly enough to change resistance as needed.
C. This is the main way resistance is controlled. The smooth muscle surrounding blood vessels can rapidly respond to hormonal or metabolic stimuli and contract/relax to adjust diameter.
D. Again, temperature is fairly constant in the body and would not be a good way to alter resistance.
Answer:
- The lac operon can be activated by the binding of allolactose to the repressor protein, releasing it from DNA and thereby allowing for transcription to occur.
- In response to low glucose levels, cAMP is upregulated; the binding of cAMP to the cAMP receptor protein triggers the activation of the operon.
Explanation:
Lactose operon or lac operon (includes lacZ, lacY and lacA genes) is found in some bacteria and the products of its genes are involved in lactose metabolism. So, this operon is active (genes are transcribed) when lactose is present and glucose is absent (or at low level). The operon is regulated by the lac repressor which acts as a lactose sensor and catabolite activator protein (CAP) which acts as a glucose sensor.
When there is lactose (in the form of allolactose) lac repressor detects it and stops being repressor. This enables transcription.
CAP detects glucose (via cAMP) and activates transcription when glucose levels are low.
Answer:
have DNA, but are NOT large or complex
Explanation:
