- Slides: 31
ANIMAL AND PLANT LIFE CYCLE
Animal life cycle Animals have life cycles that include the beginning of life, growth and development, reproduction and death. The details of a life cycle are different for different organisms.
The Life Cycle of a Butterfly Egg Butterfly Caterpillar Chrysalis or Pupa
Human life cycle
What is Metamorphosis? Metamorphosis is he changes in the shape or characteristics of an organism’s body as it grows and matures. Some animals, especially insects, have one kind of body when they are young and a very different kind of body when they are adults.
Incomplete metamorphosis A type of development that includes 3 distinct stages egg nymph adult (the baby looks like the adult)
Complete Metamorphosis A type of development consisting of 4 stages egg larva pupa adult (the baby does not look like the adult) Darkling Beetle
What is photosynthesis? n The process by which plants make their own food using sunlight, water and air is called photosynthesis.
Parts of the flower Now we are going to look more closely at the flower. Click the arrows to find the names. petal stigma anther style filament ovary sepal ovule
Life cycle of a flowering plant The fully formed seeds are carried away from the mother parent. The seed starts to grow. The pollen fertilizes the ovule and seeds start to form. The plants grow bigger and produces flowers. The bee carries the pollen to stigma of the flower
Parts of a seed
A force is a push or a pull. Forces can make things: • Speed up • Slow down • Change direction • Change shape
Forces occur in pairs and they can be Either balanced or unbalanced. When two forces are acting on an object and are not equal in size, we say the forces are unbalanced. • an object that is not moving starts to move • an object that is moving changes speed or direction • When two forces acting on an object are equal in size, but are opposite in direction, we say the forces are balanced. • an object that is not moving stays still • an object that is moving continues to move at the same speed and in the same direction
Gravity • Gravity is a pull force that makes things fall to the ground. • It is a force between ALL objects. . • Tides are caused by the gravitational pull between the earth and the moon. • It stops everything floating off the space. The force of gravity also keeps the planets in orbit around the sun. • Gravity keeps earth at a fixed distance from the sun • It keeps the moon in constant orbit around the sun. • The force of attraction or gravity depends on mass. • Objects with more mass have more gravity. Gravity
• Amount of MATTER in an object. • Weight is the measure of the force of gravity acting on an object. 0. 1 kg l. Measured (kg). in kilograms • Stays the same anywhere you go. It does not change • Weight is measured in Newtons (N) • Weight changes depending on where you are and strength of gravity.
Gravity The size of the force or gravity depends on the mass of the objects. The bigger they are, the greater the force! Small attractive force Bigger attractive force
If you were to travel to the moon, where gravity is weaker, what would change? Remember that the weight of an object changes depending on where it is, while its mass stays the same. Hence you weigh less on the moon There is less gravity on moon. • What would life be like if there were more gravity on Earth? If there is more gravity, it will be difficult to lift things up or even walk. • What would life be like if there were less gravity on Earth? If there is less gravity, objects will not fall to the ground but will float in the air instead.
Gravity on moon • The moon’s gravity is weaker than the Earth’s as it has less mass. Where will the flag be lighter? Moon (Because gravity in moon is less) Where will the bag of sugar be heavy? Earth(because there is more gravity on earth)
Air Resistance Air resistance is a force which is caused when an object moves through the air. It tries to stop or slow down the object. Air resistance is the force that is pushing up against the parachute. Gravity is pulling the skydivers towards the ground. However, they are slowed down because a force (air resistance) pushes against the inside of the parachute and they descend more slowly. Gravity and air resistance are opposing forces in this situation. air resistance gravity
How to increase air resistance Parachute What do you think happens to the speed of a falling object the greater the air resistance it has? It will slow down! The bigger something is, the more air resistance there will be pushing against it. AIR Since the parachute has a big surface area it increases the air resistance. This makes the parachute to fall slowly to the ground.
Which parachute do you think will fall the fastest, why? The small parachute will faster as it has less air resistance
How does shape affect air resistance? How to reduce air resistance? • The shape of an object can reduce air resistance. • Some objects are designed with curved and sloping surfaces to cut through the air and reduce air resistance. They are called as streamlined • Streamlined objects will have less air resistance and move through the air easily.
Which surface will the car go fastest along? Answer: Surfaces which has less or hardly any friction (smooth surface). Which surface will the car go slowest along? Surfaces that has a lot of friction (rough surface)
Water Resistance Whenever an object moves through water, it experiences the force of water resistance. Water resistance pushes against objects, making it hard for them to move through water ance t s i s e r r’s swimme force However, this also helps you to swim, as when you push against the water with your hands, the water resistance pushes back and helps you to move forward,
Streamlined Shapes The fish’s shape is streamlined to help. it move easily through the water. It does not create much water resistance so it can move through the water quickly. It has a pointed nose to cut through the water, and a smooth, low, curved back to allow the water to flow over and around it.
Streamlined Shapes The cube should have fallen the slowest through the water. It is the least streamlined shape because it has a flat surface which creates a lot of water resistance. The water pushes against the flat surface, slowing it down. The cone should have fallen the fastest through the water. It is the most streamlined shape as it has a pointed end to cut through the water.