Answer:
Positive feedback is used to build more contractions.
Explanation:
Positive feedback mechanism in humans is also observed during childbirth which is induced by the pressing of the ovarian wall by the baby.
The pressing sensation is passed to the brain via different nerves, and in response, the brain stimulates the pituitary to produce oxytocin.
Oxytocin is responsible for the contractions of the uterine muscles which cause the movement of the fetus towards the cervix, further increasing the stimulus.
The positive feedback loop continues until the baby is born.
Answer:
A) receptor, sensory neuron, interneuron, motor neuron, effector
Explanation:
In a reflex arc, the receptors present in the skin receive stimulus and generate afferent impulse. The sensory neuron transmits the impulse to the interneuron. Interneuron is present in the spinal cord and activates it. The interneuron then sends back the impulse through the motor neurons to effectors whcih are present in the muscles for the response.
Answer:
'Cross experiments done by Morgan, illustrating the X-inheritance link of a mutation Thomas Hunt Morgan moved intensely in a program of breeding and crossing miles of fruit flies at New York University in a room that was renamed the Fourth of the Flies. He tried to mutate the flies with various means (X-rays, centrifuges, etc.) .The fruit fly which has 4 pairs of chromosomes. One of those pairs was identified as containing X and Y sex chromosomes. He applied Mendelian principles in flies. Morgan's inheritance study demonstrated inheritance linked to sex, and is one of the first evidences that confirm the chromosomal theory of cross-based inheritance. In 1909, Morgan detected a fruit fly (Drosophila melanogaster) with a strange mutation which he called "white eyes", due to the coloration of his eyes (contrary to normal, which is red). Analyzing this fly under the microscope Morgan discovered that it was a male, and could use it as a stallion so that he could observe how the new characteristic of white eyes would pass from generation to generation.All the offspring of this cross will have red eyes, which He made Morgan suspect that something strange had happened, since the color of the father's eyes could not have disappeared. He decided to take a couple of "daughters flies" and cross them together, just to see what happened. Morgan's surprise was very great, observing that among the "granddaughters" flies only males had white eyes. The problem then was to explain what had happened during the hereditary transmission for the color of the white eyes only the males possessed. .
Tissue damage activates nociceptors or pain receptors in the skin. A signal is sent to the peripheral nerve to the spinal cord where neurotransmitters or chemical messengers are released. It activates other nerves to pass signal to the brain. The signals are relayed to the somatosensory cortex for sensation, frontal cortex for thinking and limbic system for emotional response.
1. Structure such as the human tailbone or appendix that evolution has reduced in size because it is no longer used = d. vestigial structure
2. study of the similarities and differences in the structures of different species:
= g. comparative anatomy
3. structure that is similar in related organisms because it was inherited from a common ancestor: = c. homologous structure
4. study of the similarities and differences in the embryos of different species: study of the similarities and differences in the embryos of different species = j. comparative embryology
5. scientist who finds and studies fossils to learn about evolution and understand the past:
= i. paleontologist
6. mistaken idea of jean baptiste lamarck that evolution occurs through the inheritance of traits that an organism develops in its own lifetime: = h. inheritance of acquired characteristics
7. process by which a single species evolves into many new species to fill available niches:
= e. adaptive radiation
8. relative ability of an organism to survive and produce fertile offspring: = k. fitness
9. structure that is similar in unrelated organisms because it evolved to do the same job, not because it was inherited from a common ancestor: = f. analogous structure
10. study of how and why plants and animals live where they do: = a. biogeography
11. process in which organisms evolve traits useful to humans because people select which individuals are allowed to reproduce and pass on their genes to successive generations:
= b. artificial selection
