A. external
These types of signals are observed when there is a cut on the body. The epidermal cells lose contact with one another and divide faster until they are in contact once again. After they come into contact, division slows down again.
Answer:
Explanation:
Australopithecina or Hominina is a subtribe in the tribe Hominini. The members of the subtribe are generally Australopithecus (cladistically including the genera Homo, Paranthropus,[2] and Kenyanthropus), and it typically includes the earlier Ardipithecus, Orrorin, Sahelanthropus, and Graecopithecus. All these related species are now sometimes collectively termed australopithecines or homininians.[3][4] They are the extinct, close relatives of humans and, with the extant genus Homo, comprise the human clade. Members of the human clade, i.e. the Hominini after the split from the chimpanzees, are now called Hominina[5] (see Hominidae; terms "hominids" and hominins).
While none of the groups normally directly assigned to this group survived, the australopithecines do not appear to be literally extinct (in the sense of having no living descendants) as the genera Kenyanthropus, Paranthropus and Homo probably emerged as sister of a late Australopithecus species such as A. africanus and/or A. sediba.
The terms australopithecine, et al., come from a former classification as members of a distinct subfamily, the Australopithecinae.[6] Members of Australopithecus are sometimes referred to as the "gracile australopithecines", while Paranthropus are called the "robust australopithecines".[7][8]
The australopithecines occurred in the Plio-Pleistocene era and were bipedal, and they were dentally similar to humans, but with a brain size not much larger than that of modern apes, with lesser encephalization than in the genus Homo.[9] Humans (genus Homo) may have descended from australopithecine ancestors and the genera Ardipithecus, Orrorin, Sahelanthropus, and Graecopithecus are the possible ancestors of the australopithecines.[8]
Groundwater supplies drinking water for 51% of the total U.S. population and 99% of the rural population. Groundwater helps grow our food 64% of groundwater is used for irrigation to grow crops. Groundwater is an important component in many industrial processes.
Answer:
The correct answer is c. 3/16.
Explanation:
In the given question two traits being studied, the traits are flower color and seed shape.
This is a typical Mendel’s dihybrid cross. According to the question purple colour (P) and round seed (R) are dominant traits.
When heterozygous purple-flowered (Pp), round-seeded (Rr) individuals are crossed, four different types of plants are produced phenotypically in the ratio 9:3:3:1.Out of 16 offspring, 9 are purple flowered, round seeded pea plants, 3 pea plants are white-flower with round seed, 3 are purple- flower with wrinkled seed and 1 pea plant is white-flowered with wrinkled seed pea plant is produced.
The Precambrian time refers to the time 4.5 billion to 542 millions year ago. This period is characterized by having reduced atmosphere and included reduced compounds. Scientists believed that atmosphere at that time was devoid of free oxygen and CO2 was present in excess. Before the complex life evolved on the Earth, the Precambrian Earth's ocean contained dissolved carbon dioxide.