Biology
Questions covered are:
What is a cell?
What is a Tissue?
What is an Organ?
What is an Organ system?
List few other organ system ?
Define Locomotion?
Define Movement ?
What is a Skeleton ?
What are the various functions of the skeleton?
What are the basic parts of the skeleton?
Write a short note on the skull?
What is a hyoid bone ?
Write a short note on backbone or spine?
Write about the rib cage?
Write a short note on limbs?
Write about bones in arm?
Write a short note on Joints?
What are Ligaments?
Which part of the body allow slight movement?
What are types of moveable joints?
Write a short note on Ball and socket Joint?
Write a short note on Pivot Joint?
Write a short note on Hinge joint?
Write a short note on Gliding joint?
Define Tendons?
Write the difference between Biceps and Triceps?
How do our leg muscle work?
Movement in animals
How do Earthworms move?
Define Exoskeleton?
How do Snails move?
How do Cockroaches move?
Define Endoskeleton?
How do fish move?
How do Snakes move?
How do Birds move ?
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What is a cell?
- A cell is a Structural or building blocks of life.
- When an organism is made up of single cell. It is called as unicellular organism.
- Ex: Amoeba, paramecium. This single cell performs all the necessary activities of the organism
- If an organism is made up of many cells, it is called as multicellular organism. Ex: All birds, animals, humans.
- Each cell of the multicellular organism perform different function.
- Ex: Red blood cells in our body carry oxygen to all parts of the body. white Blood cells are the soldiers in our body, they fight against the foreign substance.
What is a Tissue?
- A group of cell that performs a special job to gether is known as tissue.
- Ex: Muscle tissues are group of cells, specialized to contract and expand for movement of body parts.
What is an Organ?
- Tissues combine to form organ.
- Each organ performs various function of the body.
- Ex: Heart is an organ that pumps blood to various part of the body.
What is an Organ system?
- Group of organs working together to perform various activites for the proper functioning of the body is called as organ system.
- Ex: Digestive system is an organ system that helps in the digestion of food, that we eat.
- Some the organs that work together for digestion are food pipe, stomach, small intestine, large intestine.
List few other organ system ?
- Circulatory system, Respiratory system, Nervous system, Excretory system, Reproductive system, Muscular system, Skeletal system.
How the multicellular organism body system is organised?
Cells → Tissues Organs → Organ system → Body of multicellular animals.
Define Locomotion?
- The movement of an organism from one place to another in search of food, shelter is called as locomotion.
- Few examples of locomotion are Running, Walking, Swimming, Flying, Jumping, Hopping.
Define Movement ?
- Movement is defined as a state of changing the position from rest to motion or vice versa.
- Movement can be either Voluntary or Involuntary.
- Voluntary Movement. Ex: Bending down to pick up thing.
- Involuntary movement – Ex: Pumping of blood to various parts of the body.
What is a Skeleton ?
- The bones in our human body make up a framework called Skeleton.
- Skeleton systems consist of bones and connective tissue including cartilage, tendons. and ligaments.
- Adult humans have 206 bones.
What are the various functions of the skeleton?
- Skeletons provide support to our body. This framework holds us upright
- Skeleton provides protection- our body has Soft organs inside. The skull
- Skeleton provides protection. The bones protect the soft organs of our body.
- Ex: Brain is protected by Skull bone.
- The skeletal system helps in movement of the body parts.
- Skeletal systems help in making blood cells. Bones are hard outside but they are soft and spongy inside. Blood cells are made in the bone marrow.
What are the basic parts of the skeleton?
The human skeleton has four basic parts. Skull, backbone or spine, ribs and limbs.
Write a short note on the skull?
- Skull protects the brain.
- Skull contains holes for eyes, ears, nose, mouth,
- The skull has 22 bones.
- The upper part is made up of eight flat bones joined together.
- The face and jaw contain 14 bones.
- The lower jaw bone is the only moveable bone in the skull.
- Teeth are fixed to the jaw bone.
- Jaw bones help to chew the food and to talk.
What is a hyoid bone ?
- The only bone in the human body not connected to another is called a hyoid bone.
- It is a V shape bone located at the base of the tongue.
- It is connected to Skull by ligaments and muscles.
- Its function is to support the tongue and its muscles.
Write a short note on backbone or spine?
- Backbone consist of 33 small bones called vertebrae,
- Vertebrae are joined to each other by joints. This allows the movement of vertebrae.
- Backbone is attached to the base of the Skull, it forms the central supporting rod of skeleton.
- Each vertebra has holes in it through which the delicate spinal cord passes through it.
- The backbone protects the spinal cord.
- The backbone is called the spine / vertebral column.
Write about the rib cage?
- Ribs are thin, flat curved bones, it forms. a protective cage around the upper part of body.
- Rib cage consist of 24 bones arranged in 12 pairs
- All of them are joined to backbone at back, most of them are joined to breastbone in front.
- Last two pair are not joined to the breast bone
- Rib cage protects the heart, lungs, Stomach, kidneys.
Write a short note on limbs?
- The limbs consist of arms and legs.
- Longest bone of body is thigh bone is Femur.
- Femur is attached to hip bone through hip joint.
- Lower half of leg has long shin bone and calf bone.
- Ankles and feet have number of small bones.
Write about bones in arm?
- Upper arm has one long bone called Humerus.
- Lower arm has two long bones.
- Humerus is attached vertebral column through collar bone and shoulder bone
- Wrist and hands have several bones.
Write a short note on Joints?
- Two bones so are joined together, in the body through joints.
- Joints are strong, they withstand jerks.
- Ends of bones are covered with soft cartilage.
- Cartilage act as a shock absorber, reduces friction between the bones.
- Cartilage is present on upper part of the ear.
What are Ligaments?
- The bones are held together at the joints by strong, stretchy bands called ligaments.
- There are three types of movement.
- They are immovable, slightly movable, freely movable.
Which part of the body allow slight movement?
- Bones in skull (except lower jaw bone) do not allow any movement.
- Joints between ribs and breastbone allow slight movement.
What are types of moveable joints?
- Most of the joints in the human body are freely moveable joints.
- These freely moveable joints are of four main types, it depends on the type of movement they allow.
- 1. Ball and socket joint
- 2. pivot joint
- 3. Hinge joint
- 4. Gliding joint
Write a short note on Ball and socket Joint?
- This Joint allow the movement in all directions.
- In Ball and socket joint, end of one of the bone is round like ball, it fits into hollow part (Socket) in another bone.
- This joint is present in shoulder and hips.
- The bone that ends in ball is femur | humerus.
Write a short note on Pivot Joint?
- Pivot joint allows the movement in all direction Up, down, right, left, rotate.
- Pivot Joint, one of the bone end in a rounded / conical surface, it fits into dent of another bone.
- Pivot Joint is present in neck.
Write a short note on Hinge joint?
- This Joint allows movement in one plane only that is either up/down or backward | Forward.
- This joint act as hinges in door.
- Hinge joint is present in Elbow, Knee, Finger
Write a short note on Gliding joint?
- Gliding joint allow side to side movement, forward or backward movement
- This joint is present in wrist, ankles, and in vertebrae.
Define Tendons?
- Bones do not move on their own.
- Muscles attached to bones, help them to move at joints.
- Muscles are attached to bones by means of tough connecting bands called Tendons.
- Tendons helps us to move our limbs.
- Tendons are mostly collagen, they containing blood vessels and nerves.
Write the difference between Biceps and Triceps?
| Biceps | Triceps |
| Bicep is a muscle on the front part of upper arm. | Triceps is a large, thick muscle on dorsal part of upper arm. |
| The bicep includes a short head and long head, that work as Single muscle. | Triceps often appears as Shape of horseshoe on posterior aspect of arm. |
| Contraction of biceps pulls our forearm upward. | Contraction of triceps pulls our arm downward. |
How do our leg muscle work?
- when we run, our thigh and hamstring muscle bend and straighten our knee joint.
- Calf and Shin muscle bend and straighten our ankle joint.
Movement in animals
Animals have different types of skeleton
How do Earthworms move?
- Earthworms have liquid Skeleton
- Earthworms have liquid trapped in spaces inside the body.
- Muscle squeeze against the liquid, this helps the earthworm body to be firm.
- Earthworm body shape can be changed differentially by the squeezing of muscle.
- Changes in the shape of worm helps it to move along.
- Repeated contraction and expansion of muscle help the earthworm to move forward.
Define Exoskeleton?
- The hard part present outside the body of some insects and animals called as exoskeleton.
- Exoskeleton protects the soft tissues and muscles of the insects and animals.
- Grabs, Snails, and Cockroaches are some examples of Exoskeleton animals.
- Exoskeletons provide support, protection and allow movement at joints.
How do Snails move?
- Snail have a thick structure called foot.
- It is made up of strong muscles.
- It produces series of wave like movements that push snail body forward.
How do Cockroaches move?
- Cockroaches have three pairs of legs and two pairs of wings.
- Leg muscle helps in walking and climbing.
- Wings are attached to breast muscles and this helps in flying.
Define Endoskeleton?
- When the skeleton of an animal is inside the body, it is known as Endoskeleton,
- The Endoskeleton animals have backbones and they are known as vertebrates.
- All fish, amphibians, reptiles, birds, mammals have endoskeleton.
How do fish move?
- Fishes have a streamlined body, that helps them to move in water.
- Streamline means broad in the middle, narrow at the end.
- Streamline body reduces the water resistance and enables the fish to glide along the water.
- Muscles are present on both sides of the backbone in fish.
- Muscle contract on one side, expand on other this helps the fish to move side to side in zig zag pattern.
- Tail fin of fish moves along with body in zig zag pattern, it pushes against water, thereby moving the fish forward.
How do Snakes move?
- Snake is a vertebrate which means they have a backbone.
- Backbone in Snake are very flexible, they can curve their body into loops.
- When moving, body moves side to side in a wave like motion
How do Birds move ?
- Birds fly to move from one place to another
- Forelimbs are modified into wings in birds.
- Bones of birds are hollow, they are very light that helps them to rise in water.
- Breast bones of birds have strong muscles, that help birds to flap their wings & fly.
- Birds use their legs / hindlimbs run and hop.
- Some birds can even swim in water e.g. Duck.
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