Answer:
Exocytosis
Explanation:
Exocytosis is a type of active transport in which the cell membrane fuses with secretory vesicles and expels their content (water-soluble molecules, hormones, neurotransmitters, etc.) into the extracellular space. Exocytosis can be regulated or constitutive. Regulated exocytosis occurs in response of a specific signal while constitutive exocytosis secretes molecules without the need of a signal. Ca2+ is an external signal that triggers regulated exocytosis which is particularly important in neuron synapses.
The answer is D. Wild boars have a high reproductive rate and no natural predators.
In Freud’s model of
the mind, it is the id that contains a pool of primal psychic energy. It is the
id that paves way into how we deal with the everyday pleasures of our lives. The
id is governed by the pleasure principle were it is highly motivated for doing
pleasurable things like hunger, sex, thirst, and many more. It is considered to
house primal psychic energy because it is primarily consisted of all the inherited
biological aspects that are necessary in our lives. Since it contains the
pleasure principle, it is responsible for our impulses as well.
Answer:
1. the middle piece contains the chromosomes. FALSE
2. the tail contains the mitochondria. FALSE
3. the acrosome is next to the tail. FALSE
4. the head contains 46 chromosomes. FALSE
5. the acrosome is next to the nucleus, and the head contains 23 chromosomes. TRUE
Explanation:
The major parts of a mature spermatozoan in human males are the head, middle piece and the tail. The head of the sperm is a flattened and pointed structure that contains a nucleus. There are 23 chromosomes present in the nucleus. Chromosome surrounds the anterior two-thirds of the nucleus. The acrosome is a caplike vesicle and is filled with hydrolytic enzymes that help a sperm during fertilization. The middle piece contains mitochondria that provide the energy (ATP) for locomotion of sperm to the site of fertilization and for sperm metabolism.