The brain is divided into lobes that carry out different kinds of functions. There are 5 lobes in the brain:
1. Frontal lobe: Concentration, planning, problem solving, etc are the function performed by this region of the human brain.
2. Parietal lobe: Touch, pressure, taste and body awareness is processed by this lobe.
3. Temporal lobe: Long-term memory, hearing, emotions are processed in this lobe.
4. Occipital lobe: Sight is processed in this lobe.
5. Cerebellum: Coordination and balance, fine motor control are performed by this part of the brain.
The modern neuroscience has also confirmed the presence of brain waves like the alpha, beta, theta and gamma rhythm that sweep across the different lobes and regions of the brain. These waves are known to result from the collective activity of neurons in each of the regions. The brain waves are studied to check the activity of the regions that are coordinating together to carry out a particular type of task.
Answer: C. Homologous chromosomes are separated in meiosis but not in mitosis.
Explanation: There are two main types of division that take place in eukaryotic cells, mitosis, and meiosis. Mitosis is the type of division that is used for growth, repair, and replacement of tissues. Therefore it is not necessary that the cells have different chromosome numbers or are varied genetically in the daughter cells in the case of mitosis.
Meiosis is the division that takes place to form the gametes for sexual reproduction. It is important in the first stages of meiosis I, to introduce variation and to halve the chromosome number.
Chromosomes numbers are halved (from 46 to 23) during meiosis I because the gametes (sperm and egg) come together and fuse during fertilization to form a zygote. When this fusion occurs (23 from the zygote and 23 from the egg), the chromosome number needs to be returned to that of the parent cell (46).
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Genetic variation is introduced during synapsis which only occurs in meiosis, not mitosis. Homologs exchange genetic information during crossing over of synapsis. Entire chromosomes also separate during meiosis I.
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At the end of meiosis, four genetically unique cells are produced with half the number of chromosomes as the parent cell (23 cromosomes) . After the process of mitosis is completed, two cells genetically identical to each pther are produced and have the same number of chromosomes as the parent cell (46 cromosomes).
Genetic variation is actually important because of changing environmental conditions.
Answer: A
Explanation: hypothesis is something na hindi pa napatutunayan at nagpag-aaraalan while theory is something na backedup with evidences and data
Answer;
-Central nervous system
Explanation;
-The nervous system consists of two main parts: the central nervous system and the peripheral nervous system: The central nervous system is made up of the brain and spinal cord.
-The central nervous system controls most functions of the body and mind.It controls all parts of the body. It receives and interprets messages from all parts of the body and sends out instructions. The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement.
-The spinal cord serves as a conduit for signals between the brain and the rest of the body and also controls simple musculoskeletal reflexes without input from the brain.
