The correct answers are:
• Liver cells are abundant in SER.
This is because liver cells contain enzymes that metabolize various lipid-soluble compounds.
• The testes and ovaries are tissue types whose cells are abundant in SER.
This is because testes and ovaries produce steroid hormones (cholesterol is the precursor for their synthesis).
• Cholesterol is made in the SER.
ER is the organelle at which all membrane lipids are synthesized.
• Phospholipids are synthesized from cytosolic water soluble precursor molecules.
Phospholipids are the main lipids that are the main structural components of the cell membrane. They are synthesized on the cytosolic side of the ER membrane, from water-soluble cytosolic precursors.
Multi cellular colonies of plant cells adhere to each other primarily by cell walls, whereas multi cellular colonies of animal cells are typically held together by proteins
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Explanation:</u></h3>
The organisms that contains more than single single are called as multi cellular organisms. They are just opposite to the uni cellular organisms. When many identical organisms groups to form together it is called as colonies.
It will be difficult in removing any organisms that forms colonies with the multi cellular organisms.The multi cellular organism of the cells in the plants are bonded to each other with the help of the cells walls. In animal cells these are bounded together with the help of the proteins.
The membrane is selectively permeable because substances do not cross it indiscriminately. Some molecules, such as hydrocarbons and oxygen can cross the membrane. Many large molecules (such as glucose and other sugars) cannot. Water can pass through between the lipids.
