Muscular tissues - class-VIII

Epithelial tissues line the outer surface of organs and blood vessels throughout the body, as well as the inner surface of cavities in many internal organs. The human skin has up to seven layers of ectodermal tissues and guards the underlying muscles, Bones, etc.

Myoglobin is similar to hemoglobin in a way that both are oxygen-carrying protein but in a different location. It can bind to only one molecule of oxygen because it is a monomeric protein.

Aerobic respiration gives more energy but is a slow process. Anaerobic respiration like lactic acid fermentation is a fast process but releases less energy. In the case of rapid muscular contraction, the muscles perform lactic acid fermentation to provide for rapid energy intake. This process releases lactic acid which causes pain and muscle fatigue. So, the correct answer is option B.

Muscles have two major proteins actin and myosin. These are mostly contractile proteins. The energy from the hydrolysis of ATP by myosin head is directly used in the power stroke i.e., flexing of myosin head during muscular contraction. ATP is also used during muscle relaxation in the absence of ATP the myosin head will continue to bind with actin head and the muscle fibre shall remain contracted. So, the correct answer is option C.

Epithelial tissues are meant for covering and protecting the body, organs and cavities. They are not involved in body movements.
Bones form the framework of the body. They are hard and rigid. To carry out body movement property of contraction and relaxation is necessary. But bones can not contract.
Tendon is a tough fibrous connective tissue, which connects muscle to bone. Tendon does not have the property of contraction and relaxation. The ligament is a fibrous connective tissue, which connects bone to another bone. It is flexible but is not present throughout the body to carry out body movement.
Muscular tissues possess the property of contraction and relaxation. They are attached to bones. With the help of bones, muscular tissue carries out body movement. Therefore, option A is correct. 

Epithelial tissue is meant for covering and protecting the body, organs and cavities. They do not possess the property of contraction and relaxation. 
Connective tissue connects, supports and separates the organs in the body. These are present in different forms as fluid, jelly-like rigid, hard forms. 
Nervous tissue is meant for rapid transmission of the signals from one place to another. These tissues do not contract or relax.

Sarcoplasm is the cytoplasm of muscle cells or myocytes. Large amounts of glycosomes and significant amounts of myoglobin are usually found in the sarcoplasm.

Muscle tissue helps in locomotion and provides a structural framework to  the body. These have contractile proteins for contraction and relaxation. It controls voluntary and involuntary actions. It is separated into three distinct categories, smooth muscle, skeletal muscle and cardiac muscle. So, the correct answer is option C.

During embryonic development,
the cells are pluripotent, meaning they have the capability to develop and
differentiate into almost all cell types including muscle cells. Precisely, muscle
cells are formed from the mesoderm of the embryo. So, the correct answer is ‘Embryonic
development’.

Muscular tissue provides a structural framework to the body along with connective tissue. It has immense potential to contract as they have major contractile proteins like actin and myosin. The muscle contraction requires ATP which hydrolyses to ADP and inorganic phosphate to allow the overlap of the contractile proteins during muscle contraction. The calcium ions released by the sarcoplasmic reticulum acts as a cofactor to activate the contractile proteins.

Muscle tissue is the longest group of cells in the human body. These provide the structural framework to the body. They have contractile proteins which, contracts and relax to provide easy and flexible movements. Therefore, the correct answer is option B.

• Sarcoplasmic reticulum is similar to endoplasmic reticulum present in other cells. It is present in sarcoplasm (cytoplasm of the muscle cell) of the muscle fiber (muscle cell).
• The main function of the Sarcoplasmic reticulum is to store calcium ions (Ca2+).
• When nerve signal reaches the neuromuscular junction it triggers the release of calcium from sarcoplasmic reticulum which in turn facilitates muscle contraction by binding to troponin.
  
• Hence the organelle regulates the muscle contraction during internal movements is sarcoplasmic reticulum.
• So, the correct answer is'Sarcoplasmic reticulum'.

Actin is the thin filament which is present in the muscles. Myosin is the thicker filaments in the muscles. The tropomyosin is the regulatory protein which is present in the grooves of the actin filament. This is the regulatory protein which helps in the contraction and relaxation of the myosin bridge. These proteins are the structural units of the muscle fibres and help in the contraction and relaxation of muscles to allow internal movement of the involuntary muscles. 

The internal movements are performed by the involuntary muscles. The involuntary muscles function on their own and cannot be controlled willingly. The cardiac muscles are the involuntary muscles which are responsible for the pumping of the heart. The heart pumps and supplies the oxygenated blood to the different tissues in the body. The smooth muscles are responsible for carrying out peristalsis in the tube like structures of the alimentary canal. This movement helps in propelling the food in the forward direction. Both these muscles are of the involuntary type. 

• Nervpus system is divided into two types CNS and peripheral nervous system.
• The peripheral nervous system is in turn divided into the somatic nervous system and autonomic nervous system.
• The autonomic nervous system regulates the internal and involuntary movement.For example,respiration,cardiovascular,digestive etc.
• The autonomic(visceral) nervous system is again divided into the sympathetic and parasympathetic nervous system.
• Hence the sympathetic and parasympathetic are  part of nervous system regulates the internal and involuntary movement,
• So, the correct answer is 'Both A and B'.

Skeletal muscle is the most abundant of the human body's tissue. It consists of thread-like cells, of which the longest can be up to 30cm long and 0.15mm thick, that are bound together into strands by collagen filaments. So, the muscular tissue is abundant as it has around 700 muscles, which constitutes around 40% of total body weight.
So, the correct answer is option B.

In living cells, energy for immediate use is stored as molecules of ATP or adenosine triphosphate. When the energy is used, one of the phosphates attached to ATP is released, giving ADP or adenosine diphosphate. it is known as the energy currency of a cell and these are produced in the mitochondria. So, the correct answer is option B.

A fibroblast is a type of cell that is responsible for making the extracellular matrix and collagen.

• The large muscle of the upper arm flexes the arm and powerfully twists the forearm, turning the palm upward.
  
• This muscle extends from the head of the head of the humerus over the elbow to the ulna bone to help flex the elbow, and also enables pronation of the forearm.

Tendons connect muscles to bones. They are a type of connective tissue. They are strong with limited flexibility.

Glycoprotein, elastin, and collagen secretion by rat smooth muscle cells. Smooth muscle cells from rat heart secreted extracellular matrix components at high rates for many generations in culture. So the correct option is 'Muscle tissue'.