Question

SHORT-ANSWER QUESTIONS: Answer in a sentence or two.
1. What is a tissue? Give two examples.
2. Name the main organs in the digestive system. What is the main function of this system?
3. What is bone marrow? What is its main function?
4. What are the functions of the spine?
5. Why are at least two muscles needed to move a bone at a joint in one direction?
6. Name the three types of skeletons that living organisms have. Give one example of each.
7. List two adaptations in birds that help them to fly .

Answer 1

Answer:

1) A tissue is a group of similar cells performing a specific function.

Examples – Epithelial tissue, muscle tissue.

2) The liver has many functions, but its main job within the digestive system is to process the nutrients absorbed from the small intestine. Bile from the liver secreted into the small intestine also plays an important role in digesting fat and some vitamins.

3) Bone marrow is a spongy substance found in the center of the bones. It manufactures bone marrow stem cells and other substances, which in turn produce blood cells. Each type of blood cell made by the bone marrow has an important job. Red blood cells carry oxygen to tissues in the body.

4) Your spine, or backbone, is your body's central support structure. It connects different parts of your musculoskeletal system. Your spine helps you sit, stand, walk, twist and bend. Back injuries, spinal cord conditions and other problems can damage the spine and cause back pain.

Explanation:

5) Why are at least two muscles needed to move any joint in the body? A5. Generally, two skeletal muscles are joined to one bone, so that when one muscle contracts in one direction for enabling the bone to move in that specific direction; the other muscle becomes relaxed to facilitate the movement of the bone.

6)Living organisms have three type of skeletons: Endoskeleton : Example- skeletons in human beings. Exoskeleton : Example- snails. Liquid skeletons : Example- Earthworms.

• 7)THEY HAVE STREAMLINED BODY SHAPE WHICH REDUCES AIR RESISTANCE.
• THEY HAVE HOLLOW BONES THAT MAKE THEM LIGHT WEIGHT.
• THE HAVE WINGS MADE UP OF FEATHERS.
• THEY HAVE VERY STRONG CHEST MUSCLES.
• THEY HAVE A LARGE LUNGS.
• THEY ARE HIGHLY ADAPTED FOR FLIGHT.

Answer 2

Answer:

1A) A tissue is a group of similar cells performing a specific function. Examples – Epithelial tissue, muscle tissue.

2A) Digestive system is to process the nutrients absorbed from the small intestine.

3A) Bone marrow is a spongy substance found in the center of the bones. It manufactures bone marrow stem cells and other substances, which in turn produce blood cells.

4A) spine helps you sit, stand, walk, twist and bend.

5A) when one muscle contracts in one direction for enabling the bone to move in that specific direction; the other muscle becomes relaxed to facilitate the movement of the bone.

6A) Living organisms have three type of skeletons:

1.Endoskeleton : Example- skeletons in human beings.

2.Exoskeleton : Example- snails.

3.Liquid skeletons : Example- Earthworms.

7A) 1.THEY HAVE HOLLOW BONES THAT MAKE THEM LIGHT WEIGHT.

2.THE HAVE WINGS MADE UP OF FEATHERS.