Answer:
Mass extinctions have occurred throughout the planet's history and in many of them primate species also have been extinct. Climate change was the cause of some of these extinctions. For instance, between the end of the Eocene and the beginning of the Oligocene global climate became drastically colder and drier, resulting in a decrease in the food supply and in the consequent extinction of several species of adapid and omohyoid primates from America, South Europe and Asia. Extinctions due to climate change can be triggered by both catastrophic global events and the planet's natural climate dynamics.
Non-climate related environmental events also occurred throughout the evolutionary process, affecting primate populations and species and eventually causing their extinction. Changes in geographic space can lead to interaction between different species and populations and consequently competition for resources, excessive predation or pathogen transmission (a phenomenon called “Background extinction”), and all these factors also contributed to the disappearance of some primate species. This type of extinction includes those most recently caused by human action.
Answer:
Mechanical advantage of block and tackle
Explanation:
A block and tackle is characterized by the use of a single continuous rope to transmit a tension force around one or more pulleys to lift or move a load. Its mechanical advantage is the number of parts of the rope that act on the load. ... Thus, the block and tackle reduces the input force by the factor n.
Answers:
a) carcinogenic
b) anti-carcinogenic
c) carcinogenic
d) carcinogenic
e) carcinogenic
f) anti-carcinogenic
g) anti-carcinogenic
h) anti-carcinogenic
Explanation:
Cyclins are proteins that regulate the progression through the cell cycle, i.e., the transition of G1 to S phase. It is well known that high cyclin expression may lead to cell proliferation states, which is closely associated with cancer progression. Moreover, the blockage of cyclins may have an anti-carcinogenic effect by inhibiting the progression through the cell cycle. MAP kinases are serine/threonine kinases that regulate the progression through the cell cycle by phosphorylating a variety of substrates during cell proliferation. In consequence, phosphatases that inactivate MAPK kinases (i.e., by dephosphorylation) may have an anticarcinogenic effect. The p53 is a tumor suppressor protein involved in diverse cellular processes including DNA repair, cycle arrest and programmed cell death. This protein (p53) is activated by phosphorylation at target residues and phosphatases inactivate it, thereby the blockage of its degradation may have an anticarcinogenic effect. Oncogene activation (i.e., the expression of oncogenes), may alter diverse cellular processes including DNA replication, and thereby may lead to cancer development. The G-protein α subunit is a GTPase that hydrolyses GTP and thus has a major role in controlling the kinetics of the G-protein signaling cascade. Platelet-derived growth factor receptors (PDGFR) are kinase receptors that play roles in regulating cellular differentiation, cell proliferation and cell growth. PDGFR receptors are present on the surface of normal cells, however, it has been shown that mutations of the PDGFR genes that lead to their high expression lead to uncontrolled cell growth and consequently cause cancer (i.e., by increasing PDGF signaling).
Answer:
Option (A).
Explanation:
Sociology may be defined as the subject that focus on the study of development and social interaction in society. Sociology is also known as the general science of the society.
Amy and Katherine are the member of same team and Amy shows fast development than Katherine. They both are competitor of each other. This is human behavior to jealous with the person that perform better than them. Here, the development of Amy makes jealous to Katherine and she starts disliking Amy.
Thus, the correct answer is option (A).