Almost the entire system of an embryo is made of cartilage,
whereas that of an adult is mostly made of bones.
<span>An </span>embryo<span> <span>is a
multicellular diploid eukaryote in an early stage of embryogenesis, or
development. In general, in organisms that reproduce sexually, an </span></span>embryo<span> develops from a zygote, the single cell
resulting from the fertilization of the female egg cell by the male sperm cell.</span>
<span>Biologically, an </span>adult<span> is a human being or other organism that has
reached sexual maturity.</span>
The correct answer between all
the choices given is the first choice or letter A. I am hoping that this answer
has satisfied your query and it will be able to help you in your endeavor, and
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Answer:
<u>Luteinizing hormone </u>(LH) stimulates Leydig cells to secrete testosterone
<u>Follicle stimulating hormone (FSH)</u> stimulates Sertoli cells to secrete protein and other molecules required for spermatogenesis
Explanation:
Under the influence of gonadotropin-releasing hormone, the anterior pituitary releases luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In males, LH stimulates interstitial cells of testes (Leydig cell) to secrete the hormone testosterone. FSH acts indirectly to stimulate spermatogenesis by causing the release of androgen-binding protein (ABP) from the Sertoli cells. The function of ABP is to maintain the higher concentrations of testosterone to stimulate the final steps of spermatogenesis in the seminiferous tubules.
Answer:
Fossils of mollusks would be found in lower strata than that of arthropods
Explanation:
Fossils are found in different layers of sedimentary rocks. The fossils of organisms that evolved earlier are found in the lower strata while those evolved later are preserved as fossils in the upper strata. If mollusks evolved before arthropods, fossils of arthropods would be present in upper layers while those of mollusks would be found in deeper layers.
Answer:
brainliest please
Explanation:
Breathing is the physical process where you inhale and exhale air in and out of your lungs. Respiration is a chemical reaction where Oxygen is used to breakdown Glucose in order to generate energy which is then used by the cell to function.
Answer:
A. donation of excited electrons by chlorophyll a to a primary electron acceptor
Explanation:
Photosystems are structures located at the thylakoid membrane that act to harvest energy light in order to convert it into chemical energy. Each photosystem is composed of a light-harvesting complex and a core complex, which in turn is composed of a reaction center. The photosynthetic reaction centers are multi-protein complexes that use light energy to catalyze the electron transfer across the chloroplast thylakoid membrane against a thermodynamic gradient. Moreover, antenna pigments are pigments that capture the energy from photons in order to transfer energy to other pigments in the photosystem (e.g., chlorophyll B and carotenes are antenna pigments, whereas chlorophyll A is the core pigment). Light energy absorbed by antenna pigments in the photosystems is transferred to the reaction center chlorophyll A molecules, thereby exiting electrons in the reaction center. A reaction center consists of two chlorophyll A molecules, which donate electrons to the primary electron acceptor.