C) As the trait will then pass to others without it and through natural selection will become abundant
Hormones are the chemicals that play important role in human body. The changes in human body is mainly related to the hormonal changes. In case of a female, hormones play a very significant role. If the diet is unhealthy or laden with extra hormones or chemicals that mimic hormones, the female my experience and early puberty. In such case, the menarche can be reached earlier than expected.
Thus, diet laden with hormone mimicking chemicals are expected of contributing to girl's earlier experience of menarche.
Answer:
a. midbrain
b. thalamus; hypothalamus, epithalamus
c. cerebral aqueduct
d. medulla oblongata
e. choroid plexus
f. pons; medulla oblongata; midbrain
g. hypothalamus
h. cerebrum
i. epithalamus
j. cerebrum
k. cerebellum
Explanation:
The brainstem is the posterior part of the brain that connects the cerebrum with the spinal cord. The brainstem can be divided into three parts: midbrain (i.e., mesencephalon), the pons (i.e., metencephalon), and the medulla oblongata (i.e., myelencephalon). The mesencephalon is a region of the brain composed of the tectum and tegmentum, which play fundamental roles in motor movement, auditory and visual processing. The corpora quadrigemina is found at the tectum region of the midbrain. The diencephalon is a small part of the brain located above the brainstem (between cerebral hemispheres); which contains the thalamus, hypothalamus, subthalamus, and epithalamus. In turn, the epithalamus is composed of the habenular nuclei, pineal gland, and the stria medullaris thalami. The cerebral aqueduct is a narrow channel (approx. 15 mm) in which the cerebrospinal fluid flows between the third ventricle and the fourth ventricle. The medulla oblongata is a long stem-like structure located in the brainstem of the brain, just in the place where the brainstem connects the brain to the spinal cord. The choroid plexus is a complex network of capillaries located at the cerebral ventricles of the brain, which serve to produce cerebrospinal fluid through ependymal cells that line the ventricles of the brain. The cerebellum is a major structure of the hindbrain and consists of the cerebellar cortex and a core of white matter having the cerebellar nuclei.
