If the mass of an object increases, the force acting on it, such as gravitational force, also increases.
true or false ?

True. Mass refers to how much matter an object contains. Gravity refers to the attractive pull between two objects that have mass. Gravitational force is directly proportionate to the mass of an object. Therefore if there is an increase in the mass of an object there is also an increase in gravitational pull. To put it simply, the larger the objects, the greater the gravitational pull. A good example is between the size of the Earth and the moon. Earth is larger in size therefore the gravitational pull you experience here on Earth is greater than the moon's because the moon is much smaller in size compared to the Earth’s surface. 

An autotrophic protist - they can perform photosynthesis and mainly consist of unicellular algae. they can be divided into number of systematic group according to the shape of their cell and the type of photosynthetic pigments they use.