<span>Which of the following is a structure in some plants that produces male sex cells?
Answer: antheridium
</span><span>What is a life cycle that alternates between sexual and asexual reproduction called?
Answer: alternation of generations</span>
Answer:
Troponin and calcium ions.
Explanation:
Troponin is a component of thin filament along with tropomyosin and actin. It is a protein complex to which calcium binds and start the production of muscular force.
Calcium also playing a very important role in muscle contractions, it binds with troponin and helping to move tropomyosin.
When calcium ion attached to troponin, then conformational changes occurs in troponin shape and moves which allow tropomyosin going away from its inhibitory position from the myosin-binding sites on actin. After this, the energized myosin head starts binding to the actin molecules and starts the cross bridge cycle, which helping in shortening the muscle's fiber.
In a hydra, digestion is completed intracellularly.
Hence option (a) is correct.
Small, freshwater organisms of the phylum Cnidaria and class Hydrozoa are grouped under the genus Hydra. They are indigenous to temperate and tropical climates.
The digestion takes place intracellularly in Hydra.
Because of their ability to regenerate and the fact that they don't appear to age or experience old age, hydra have drawn the attention of biologists.
Like most other cnidarians, hydras have a pretty straightforward digestive system.
They have a two-way digestive system, which differs from mammals in that food and waste enter and exit through the same aperture. A "blind gut" is the name for this configuration.
The center of the hydra's body is occupied by its digestive tract.
Learn more about Hydra here brainly.com/question/1808325
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Answer:
Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. ... Blood vessels nourish the cells in the hair bulb, and deliver hormones that modify hair growth and structure at different times of life, if that answers your question.
Explanation: