a
Answer:
bone is the everything of movement
Carbohydrates are mainly transported in the phloem in the form of sucrose. The cell membrane of the sieve cells contains pump proteins that actively convey sucrose into the vascular pathways.
Answer: C): the number of unpaired electrons.
Explanation: A covalent bond is a type of chemical bond formed by sharing equal number of electrons between two non-metal atoms so that both can attain the a stable octet or duplet structure of noble gases. The electrons shared by two non-metal atoms are the unpaired electrons. For example, in the formation of a chlorine molecule, a chlorine atom has seven valence electrons and electrons usually occur in pairs. Having seven valence electrons means that a chlorine atom has three pairs of electron and one unpaired electron in its outermost shell. The two chlorine atoms will combine together each donating its unpaired electron to be shared, thus leading the two atoms to attain stable octet structure of Argon.
Answer:
Electromagnetic waves can travel through a vacuum, that is an empty space, whereas mechanical waves cannot. They need a medium to travel such as water or air. Ripples in a pond are an example of mechanical waves whereas electromagnetic waves include light and radio signals, which can travel through the vacuum of space.
Explanation:
Answer:
1. protein synthesis - (b) rough ER
2. protein modification and sorting - (c) Golgi apparatus
3. macromolecule digestion - (d) lysosomes
4. lipid synthesis - (a) smooth ER
5. autophagy - (d) lysosomes
6. cisternal maturation - (c) Golgi apparatus
7. calcium ion storage - (a) smooth ER
8. poison detoxification - (a) smooth ER
Explanation:
Rough ER or rough endoplasmic reticulum with the help of ribosomes is responsible for protein synthesis and their subsequent transport to various other parts of the cell that is why both these organelles are also known as protein factory.
Soon after proteins are synthesized with the help of rough ER, they are transported to another network of organelle known as golgi apparatus. In golgi apparatus, the nascent protein is further modified and sorted. Modification and sorting of proteins help in identifying their final destination i.e. whether the protein is meant for mitochondria or plasma membrane or some other organelle. Maturation of cisternae also takes place in golgi apparatus.
Smooth ER or smooth endoplasmic reticulum is responsible for lipid synthesis, storage of calcium ions and poison detoxification. Most of the steroid hormones, triglycerols etc. are synthesized in the smooth endoplasmic reticulum. Smooth ER also stores calcium ions so that whenever they are required they can be sequestered back into the cytosol. Poison detoxification occurs in the smooth ER of liver because the enzymes present in the liver are capable of converting such hydrophobic substances into hydrophilic substances so that they could be easily secreted out of the body.
Lysosome is the organelle which is responsible for macromolecule digestion and autophagy. Lysosomes have very low pH and a lot of hydrolyzing enzymes which can easily digest macromolecules. Autophagy is a self degradable process in which damaged cells are eaten or destroyed by lysosomes so that their macromolecules could be broken down into their monomers so that they can be reused by our body.
