Answer:
the male part of a flower is called the stamen, it consists of a long slender stalk, the filament, with a two-lobed anther at the tip.
the female part of a flower is called the pistil, it consists of the stigma, the style, the overy and the ovule.
Answer:
A) Calcitonin injection
Explanation:
Parafollicular cells or C-cells of the thyroid gland produce a hormone which is involved in the regulation of calcium levels in the blood. This hormone is Calcitonin. It works in an antagonistic manner with the Parathyroid hormone (PTH). Calcitonin decreases the calcium level in the blood by increasing absorption of calcium ions in bones. In osteoporosis, when the patient is given the injection of hormone calcitonin, it produces and increase in bone mass because it negatively affects the rate of absorption of bone by the osteoclasts.
Answer:
The correct answer is 3: "<em>High levels of Ca2+ are expected to be found </em><em>within the sarcoplasmic reticulum</em>".
Explanation:
Muscular contraction is a highly regulated process that depends on free calcium concentration in the cytoplasm. Amounts of cytoplasmic calcium are regulated by <u>sarcoplasmic reticulum</u> that functions as a storage of the ion.
When a nerve impulse reaches the membrane of a muscle fiber, through acetylcholine release, the membrane depolarizes producing the entrance of calcium from <u>extracellular space</u>. The impulse is transmitted along the membrane to the sarcoplasmic reticulum, from where calcium is released. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. The calcium channel in the sarcoplasmic reticulum controls the ion release, that activates and regulates muscle contraction, by increasing its cytoplasmic levels. When <em>calcium binds to the troponin C</em>, <em>the troponin T alters the tropomyosin by moving it and then unblocks the binding sites,</em> making possible the formation of <em>cross-bridges between actin and myosin filaments.</em> When myosin binds to the uncovered actin-binding sites, ATP is transformed into ADP and inorganic phosphate.
Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
Answer:
This question is in my stored notes read below
Explanation:
Pancreas is an exocrine gland as it has a duct to store pancreatic juice secreted by the pancreas and use it whenever required. It is considered as a endocrine gland as it does not have a duct to store the hormones insulin and glucagon which are directly supplied to the blood stream.
