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love history [14]
3 years ago
15

Which type of spacecraft is always manned?

Biology
2 answers:
egoroff_w [7]3 years ago
7 0

Answer:

Space shuttles are a type of spacecraft that are manned

according to my school.

Explanation:

hope it helps

zheka24 [161]3 years ago
3 0

Answer:

A piloted spacecraft is always manned

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sweet [91]

Answer:

15

Explanation:

the atomic number is the number above the symbol. the number below is the atomic mass.

4 0
2 years ago
A patient is receiving gabapentin (neurontin), an anticonvulsant, but has no history of seizures. the nurse expects that the pat
Diano4ka-milaya [45]
<span>Actually here in this case, the nurse actually expects that the patient may get relieved from any sorts of nerve pain and tingling in any parts of the body, by receiving gabapentin, which is also a anticonvulsant OR antiepileptic drug, hence it can used for treating other nerve problems along with seizures and may also be used at initial stages for prevention of any medical complications.</span>
6 0
3 years ago
Following antigenic stimulation, phosphorylation of _________ relieves inhibition of the transcription factor
Maru [420]

Answer: zap70, ITAM.

Explanation:

An antigen is any substance that is capable of stimulating an immune response by activating lymphocytes, which are the body’s infection-fighting white blood cells. Examples of antigens could be proteins that are part of bacteria or viruses or components of serum and red blood cells from other individuals, all of them are foreign antigens originated outside the body. However, there can also be autoantigens (which are self-antigens), originated within the body. In normal conditions, the body is able to distinguish self from nonself. <u>And the antigens that represent a danger induces an immune response by stimulating the lymphocytes to produce antibody or to attack the antigen directly</u>. This is called an antigenic stimulation of the immune system.

ZAP-70 (Zeta-chain-associated protein kinase 70) is a protein that is part of the T cell receptor, thereby it plays a critical role in T-cell signaling. When the TCR (receptor of T cells) is activated by the presentation of the specific antigen through the MHC, a protein called Lck acts to phosphorylate the intracellular CD3 chains and the ζ chains of the TCR complex, allowing the binding of the cytoplasmic tyrosine kinase, ZAP-70. Lck then phosphorylates and activates ZAP-70, which in turn phosphorylates another molecule in the signaling cascade called LAT (short for Linker of Activated T cells), a transmembrane protein that serves as an anchor site for several other proteins. The tyrosine phosphorylation cascade initiated by the Lck culminates in the intracellular mobilization of calcium ion (Ca2+) <u>and the activation of important signaling cascades within the lymphocytes.</u> These include the Ras-MEK-ERK pathway, which is based on activating certain transcription factors such as NFAT, NFκB and AP-1. These transcription factors regulate the production of of certain gene products, most notably cytokines such as interleukin-2 that promote the long-term proliferation and differentiation of activated lymphocytes.

The ITAM motifs (immunoreceptor tyrosine-based activation motif) are sequences of four amino acids present in the intracellular tails of certain proteins that serve as receptors within the immune system. Thus, <u>some receptors such as the TCR have ITAM sequences that, when activated, trigger an intracellular reaction based on consecutive phosphorylations</u>.  Kinases are recruited for this purpose.

So, ZAP-70 is a protein tyrosine kinase with a role in T-cell receptor signal transduction. During T-cell activation, ZAP-70 binds to ITAM and becomes tyrosine phosphorylated. The binding of ZAP-70 to the phosphorylated ITAM is able to activate its kinase activity, <u>and relieves the inhibition of the transcription factor which regulates genes that are involved in the immune reaction</u>.

6 0
3 years ago
What molecule loses electrons in the cellular respiration?
Goryan [66]

Answer:

C. glucose

Explanation:

3 0
3 years ago
What has a neutral charge ?
Bezzdna [24]
Neutron has no charge, therefore it is neutral
5 0
3 years ago
Read 2 more answers
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