Specific excretory organs are absent in unicellular organisms belonging to the<u> phylum Porifera.</u>
The organisms of the phylum Porifera are classified under the kingdom Animalia and they lack specific organs in their bodies.
The word "Porifera" refers to pore-bearing organisms.
These animals have loosely organized cells and are found in freshwater marine ecosystems.
On their body, a large number of pores - Ostia - are present which perform various functions such as excretion.
However, respiratory gases and waste materials are exchanged through a diffusion process.
Moreover, in them, reproduction takes place through fragmentation and budding.
If you need to learn more about excretory organs click here:
brainly.com/question/28302813
#SPJ4
Agoraphobia is the fear of being out in the open. People with Agoraphobia are scared of leaving home, crowded places and places that escape would be difficult.
Introduction :-)
The <em>amniotic fluid</em> is the protective liquid contained by the <em>amniotic sac</em> of a <em>gravid amniote</em>. This <em>fluid</em> serves as a cushion for the growing <em>fetus</em>, but also serves to facilitate the exchange of nutrients, water, and biochemical products between <em>mother</em> and <em>fetus</em>.
Importance :-)
- <em>It helps to protect the fetus from trauma to the maternal abdomen.</em>
- <em>It cushions the umbilical cord from compression between the fetus and uterus.</em>
- <em>It has antibacterial properties that provide some protection from infection.</em>
- <em>It serves as a reservoir of fluid and nutrients for the fetus.</em>
<em></em>
Formation :-)
<em>Amniotic fluid </em>is present from the formation of the <em>gestational sac.</em> <em>Amniotic fluid </em>is in the <em>amniotic sac.</em> It is generated from <em>maternal plasma</em>, and passes through the <em>fetal membranes</em> by <em>osmotic</em> and <em>hydrostatic forces</em>. When <em>fetal kidneys</em> begin to function around week 16, <em>fetal urine</em> also contributes to the <em>fluid.</em> In earlier times, it was believed that the <em>amniotic fluid</em> was composed entirely of <em>fetal urine</em>.
The <em>fluid</em> is absorbed through the <em>fetal tissue</em> and <em>skin</em>. After <em>22 to 25 week </em>of<em> pregnancy</em>, <em>fraternization</em> of an <em>embryo's skin</em> occurs. When this process completes around the <em>25th week</em>, the<em> fluid</em> is primarily absorbed by the <em>fetal gut</em> for the remainder of <em>gestation</em>.
<em>Contents :-)</em>
At first, <em>amniotic fluid</em> is mainly water with <em>electrolytes</em>, but by about the <em>12-14th week</em> the <em>liquid</em> also contains <em>proteins, carbohydrates, lipids and phospholipids, and urea</em>, all of which <em>aid</em> in the growth of the <em>fetus</em>.
Hope its helpful :-)
If so, please mark me as brainlist :-)
