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Muscles are soft tissues in the human body made up of special cells called muscle fibers that can contract and relax. They help the body move by pulling on bones through tendons. Muscles are elastic, which means they can contract without breaking and then return to their original shape. There are over 600 muscles in the human body, and together with bones and joints, they allow all kinds of body movements. Muscles also protect our organs and help maintain posture and body stability. They can be divided into three main types: skeletal muscles, which are attached to bones and help with voluntary movements; smooth muscles, found inside organs and responsible for involuntary actions; and cardiac muscles, which are found only in the heart and control heartbeat. The nervous system directs muscles to contract and relax so we can move and perform tasks. Muscle contractions convert chemical energy into mechanical energy…

Joints in the human body are of three main types: fibrous, cartilaginous, and synovial. Fibrous joints are immovable and hold bones tightly together, like in the skull. Cartilaginous joints allow limited movement and connect bones with cartilage, found in areas like the spine. Synovial joints are freely movable and the most common, allowing different kinds of motion. Among synovial joints are hinge joints, which move back and forth like elbows and knees. Ball and socket joints enable rotation and movement in many directions, like shoulders and hips. Pivot joints allow bones to rotate around each other, as seen in the neck. Saddle joints permit movement back and forth and side to side, such as in the thumb. Condyloid joints allow up and down and side to side movement without rotation, found in wrists and fingers. Gliding joints let bones slide over each other, found in wrists and ankles. These joints…

Joints are places where two or more bones meet in your body, and they help you move easily, like bending your arms and legs. Joints work as connectors, letting bones move in different ways, such as straightening, bending, or turning. They are really important for dancing, running, and doing almost any movement. Inside joints, there are also special parts to help bones move smoothly and stop them from rubbing together. Without joints, your bones would be stiff, and you wouldn't be able to move much at all.​

1. Joints are places where two or more bones meet in the body.

2. They help the body move by allowing bones to bend, twist, and turn easily.

3. Joints act like connectors that make it possible to do activities like walking, dancing, and playing.

4. There are different types of joints: some move a lot (like hips and shoulders), and some barely move (like in the…

The human skeleton is the internal framework of the body made up of about 206 bones in adults, along with cartilage, ligaments, and tendons. It is divided into two main parts: the axial skeleton, which includes the skull, vertebral column (spine), and rib cage; and the appendicular skeleton, which comprises the bones of the limbs and the shoulder and pelvic girdles. The skeleton provides shape and support to the body, protects internal organs like the brain, heart, and lungs, enables movement by serving as attachment points for muscles, stores minerals such as calcium, and produces blood cells in the bone marrow. It plays essential roles in the body's structure, protection, movement, mineral storage, and blood cell production.​

1. Protection: It protects vital internal organs, such as the skull protecting the brain and the rib cage protecting the heart and lungs.

2. Movement: It enables movement by serving as attachment points for muscles;…

Your heart is a little muscle that beats and pumps blood.

Your lungs help you breathe in fresh air.

Your stomach is where the food goes to get digested.

Anatomy helps us understand these parts and how they fit together inside you so you can move, play, and grow.

Joints are places where two or more bones meet in our body. They help us move, bend, and twist easily. Without joints, our body would be stiff and we couldn't move well. Some joints move a lot, like shoulders and hips, and some don't move at all, like in our skull. Joints are covered with soft cartilage, which keeps bones safe and helps them move smoothly. Ligaments hold the bones together at the joints. Joints make our body flexible and are very important for every movement

A muscle is a part of your body that helps you move by stretching and squeezing, which we call contracting and relaxing. Muscles are elastic, they don’t break easily, and they work together with your bones to control movement. Muscles also protect your organs inside the body.​

Muscles and Movement

Muscles connect to bones using strong fibers called tendons. When your muscles contract, they pull on your bones, and this is how you move your arms, legs, and other parts of your body. Your brain and nerves help control when and how your muscles move.​

How Many Muscles

You have more than 600 muscles all over your body, including muscles like your biceps, abs, quadriceps, triceps, pectorals, glutes, calves, and others.​

Muscles Protect

The skeletal system is like the body's strong frame made of many bones, and it keeps your body standing tall and moving easily. If you didn't have bones, you'd be all wobbly, like jelly! Bones help protect important things inside you, such as your brain, heart, and lungs. Joints are places where bones meet and bend, letting you move your arms and legs, and cartilage is the soft, bendy part found in places like your nose and ears.

The respiratory system is the part of your body that helps you breathe in air and get oxygen from it. It also helps you breathe out the gas your body doesn’t need — called carbon dioxide.

The nervous system is the body's control and communication network, made up of the brain, spinal cord, and a vast network of nerves. It coordinates all bodily activities by transmitting signals to and from different parts of the body, allowing an individual to sense the environment, think, move, and respond to both internal and external changes.​

Blood moves through veins, arteries, and capillaries with the help of the heart.​

The heart pumps blood to the lungs to get oxygen and remove waste.​

Oxygenated blood is sent from the heart to all organs.​

Organs use oxygen and nutrients, then send the now deoxygenated blood with waste back to the heart.​

1. The digestive system breaks down the food we eat into small parts so our body can use the nutrients for energy and growth.

2. Digestion starts in the mouth where food is chewed and mixed with saliva, which contains enzymes to begin breaking down food.

3. The chewed food moves down the oesophagus (food pipe) into the stomach.

4. In the stomach, food is mixed with stomach acids and digestive juices that break it down further and kill bacteria.

5. The food then enters the small intestine, where it is mixed with bile from the liver and enzymes from the pancreas to digest proteins, fats, and carbohydrates.

6. The inner walls of the small intestine have villi, tiny finger-like projections that absorb nutrients into the bloodstream.

Reproduction in plants is the way plants make new plants, or offspring, so life continues. There are two main ways: asexual (one parent) and sexual (two parents).

• Asexual reproduction: One plant creates new plants by itself, without seeds or joining with another plant. This can happen through parts like roots, stems, or leaves (for example, by cutting a stem and planting it).

• Sexual reproduction: Two plants are involved. The male and female parts join together (pollen from one meets the ovule from another) to make seeds. These seeds can grow into new plants.

Simple Explanation

• Asexual reproduction is like making a copy of the parent plant using its parts.

• Sexual reproduction is like mixing parts from two plants. The flower makes seeds after pollen joins with the ovule, and these seeds become new plants.

Photosynthesis is the way plants use sunlight to make their own food and release oxygen.

1. Plants take in sunlight using a green pigment called chlorophyll in their leaves.

2. Roots absorb water from the soil and send it to the leaves.

3. Leaves soak up carbon dioxide from the air through small holes called stomata.

4. Using sunlight energy, plants change water and carbon dioxide into sugar (food) and oxygen.

5. The plant uses sugar to grow, and lets oxygen out into the air for other living things to breathe.

Photosynthesis is the process plants use to convert sunlight, water, and carbon dioxide into food in the form of glucose. Chlorophyll in the leaves absorbs sunlight to power this process. Oxygen is released as a byproduct. This process happens mainly in the leaves’ chloroplasts. Photosynthesis provides energy for plants and produces oxygen for other living things.

The skeletal system is the body's internal support structure made up of bones, cartilage, ligaments, and tendons. It provides shape to the body, supports and protects vital organs, allows movement by working with muscles, produces blood cells, stores minerals, and helps maintain overall bodily structure and function. The system consists of 206 bones in adults, divided into the axial skeleton (skull, vertebral column, ribs, sternum) and the appendicular skeleton (shoulder girdle, pelvic girdle, limbs). It plays crucial roles such as protecting organs like the brain and heart, facilitating movement, and housing bone marrow that produces blood cells.

Relate

1. Photosynthesis is how green plants make their own food.

2. Plants use sunlight, carbon dioxide (CO₂), and water (H₂O) for this process.

3. The green pigment chlorophyll in leaves helps absorb sunlight.

4. This process mainly happens in the leaves, inside chloroplasts.

5. Plants take in carbon dioxide from the air through tiny holes called stomata.

6. They absorb water from the soil through their roots.

• Definition and Purpose: Reproduction is the biological process by which organisms produce new individuals—known as offspring—from their parent(s). Its fundamental purpose is to ensure the survival and continuity of the species across generations.

• Asexual Reproduction: This mode involves a single parent and does not involve the fusion of sex cells (gametes). The offspring produced are typically genetically identical to the parent (clones). Examples include binary fission in bacteria, budding in yeast and Hydra, and fragmentation in starfish.

• Sexual Reproduction: This mode typically involves two parents (male and female) and the fusion of specialized reproductive cells called gametes (like sperm and egg) to form a zygote.

• Genetic Variation: Sexual reproduction is crucial because it introduces genetic variation in the offspring due to the combination of DNA from two parents. This variation is the raw material for evolution and natural selection, allowing a species to adapt to changing environments. Asexual reproduction offers very little to no genetic variation.

• Role in Life Cycle: Reproduction is…