Answer:
Biodiversity hotspots are regions under surveillance of humans where threatened and endemic species of flora and fauna are grown. These regions have been identified as some of the world's most important ecosystems.
The two criteria for designation as a biodiversity hotspot are:
1. It must possess at least 1500 vascular plant species as endemics : It means the region must have a high percentage of plant species which are found no where else in the world.
2. It must have 30% or less native vegetation : It means that the plant species population is endangered and threatened to extinction.
Calcium levels in the body are maintained by hormones. If the blood calcium level rises above a set point, calcitonin is secreted by the thyroid gland and sets into motion responses to lower the blood calcium back to the set point. If the blood calcium level falls below a set point, the parathyroid gland secretes parathyroid hormone that sets into motion responses to raise the blood calcium. These homeostatic responses are examples of:
a. positive feedback
b. effectors
c. sensors
d. negative feedback
Answer:
d. negative feedback
Explanation:
Negative feedback responses are the ones that counteract the change. Any alterations in the internal body conditions such as blood calcium levels are sensed by receptors. The information is sent to the brain which in turn commands the effectors such as endocrine glands to secrete the required hormones to restore the normal conditions. Here, changes in the calcium levels are counteracted by the secretion of calcitonin and parathyroid hormones and the calcium is maintained within a narrow range. This represents negative feedback.
A) plant because it does photosynthesis
It happens because of Point mutation
Explanation:
A point mutation can be understood as when one nucleotide is added, deleted or changed. Through change in DNA structure a gene can be altered and it is called mutation. Point mutation’s other term is insertion as well as deletion. It mostly involves in substitution.
Rarely, Point mutation is responsible for huge change. Basically, two types of point mutation happen. They are transition or transversion mutations.
Answer:
C. <em>Clostridium</em> and <em>Bacillus</em>.
Explanation:
<em>Bacillus </em>and <em>Clostridium</em> are the gram-positive bacteria and form endospores. Endospores are the resistant dormant structures formed by some gram-positive bacteria.
These bacteria form the endospores within their vegetative cells. The endospores are highly resistant to environmental stress conditions and make these bacterial genera the dangerous pathogens.
