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3 years ago

What would happen if your heart valves stopped working?

Biology

1 answer:

LiRa [457]3 years ago

7 0

Answer:

In heart valve disease, one or more of the valves in your heart doesn't work properly. Your heart has four valves that keep blood flowing in the correct direction. In some cases, one or more of the valves don't open or close properly. This can cause the blood flow through your heart to your body to be disrupted.

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What could happen if a person doesn’t get the proper amount of protein in his or her diet?

NISA [10]

Protein deficiency can cause muscle cramping, weakness, and soreness. If you aren't consuming enough protein, your body will start to take protein from your skeletal muscles, which will lead to your muscles wasting over time.

3 0

2 years ago

Read 2 more answers

The rain forests of the world trap a large amount of carbon dioxide, a greenhouse gas. Every year, however, more rain forest is

IrinaVladis [17]

Carbondioxide, being a green house gas has the property of trapping the heat from the sunlight and thus increasing the temperature of the place. As more and more rain forests are cut down and burned, there is an increase in this green house gas in the atmosphere thus leading to a steady increase in the temperatures.

As we look at the graphs that are given, we can see that the graph C shows the steady increase in the temperature as the time passes. Hence option C is the right answer

7 0

3 years ago

Read 2 more answers

How are the law of independent assortment and the law of segregation different?

san4es73 [151]

Hi there!

The law of independent assortment says that the traits are randomly selected, there is no pattern to how they are sorted. The law of segregation says that the traits are divided between each gamete, using a pattern to sort them.

Hope this helps!! :)

7 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. And the antigens that represent a danger induces an immune response by stimulating the lymphocytes to produce antibody or to attack the antigen directly. 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+) and the activation of important signaling cascades within the lymphocytes. 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, some receptors such as the TCR have ITAM sequences that, when activated, trigger an intracellular reaction based on consecutive phosphorylations. 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, and relieves the inhibition of the transcription factor which regulates genes that are involved in the immune reaction.

6 0

2 years ago

Mention the 10 Phylla of plants. .

victus00 [196]

1. Phylum Heptophyta- Non Vascular Plants (Bryophytes)

Common Name: Liverworts

Estimated Number of Species: 9,000

2. Phylum Anthocerophyta- Non Vascular Plants (Bryophytes)

Common Name: Hornworts

Estimated Number of Species: 100

3. Phylum Bryophyta- Non Vascular Plants

Common Name: Mosses

Estimated Number of Species: 15,000

4. Phylum Lycophyta- Vascular Plants (Seedless Vascular Plants)

Common Name: Lycophytes

Estimated Number of Species: 1,200

5. Phylum Pterophyta- Vascular Plants (Seedless Vascular Plants)

Common Name: Pterophytes

Estimated Number of Species: 12,000

6. Phylum Ginkgophyta- Vascular Plants (Seed Plants: Gymnosperms)

Common Name: Ginkgo

Estimated Number of Species: 1

7. Phylum Cycadophyta- Vascular Plants (Seed Plants: Gymnosperms)

Common Name: Cycads

Estimated Number of Species: 130

8. Phylum Gnetophyta- Vascular Plants (Seed Plants: Gymnosperms)

Common Name: Gnetophytes

Estimated Number of Species: 75

9. Phylum Coniferophyta- Vascular Plants (Seed Plants: Gymnosperms)

Common Name: Conifers

Estimated Number of Species: 600

10. Phylum Anthophyta- Vascular Plants (Seed Plants: Angiosperms)

Common Name: Flowering Plants

Estimated Number of Species: 250,000

6 0

3 years ago