The reproductive part of a plant is the flower.

Lactic acid It is produced during heavy exercise as sufficient oxygen is not available to muscles.

Water absorption through roots can be increased by keeping the plants under the fan.

Difference between an open circuit and a closed circuit

Difference between convection and conduction

The two effects of electric current are
(i) Heating effect
(ii) Magnetic effect

The steps involved in the process of fertilisation are
(i) After pollination, pollen grains start growing into a pollen tube on the stigma passing through pistil.
(ii) The tube extends through the style and reaches to the ovules.
(iii) The pollen tube carries the male gametes called pollen grains.
(iv) Male gametes fuse with the egg (female gamete) present inside ovule and forms a zygote. This process is called fertilisation.
(v) Later zygote develops into an embryo and ovules develop into a seed.
(vi) Thus, seed carries an embryo with stored food and is covered by a hard protective covering called seed coat.

When we work hard or perform physical activity (like running, swimming, cycling), we need more energy. To fulfil the energy requirement, we breathe faster. Fast breathing helps in supply of more oxygen to our cells. Due to this, rate of breakdown of food increases and more energy is released. The rapid breakdown of food makes us to feel more hungry.

The vertical section of heart shows that heart is divided into four compartments called as chambers.
(a) The upper two chambers of heart are called atria or atrium.
(b) The lower two chambers of heart are called ventricles.

(a) The name of the given instrument is stethoscope.
(b) Labelled diagram of stethoscope.

Characteristics of the image formed by the plane mirror are
(i) It is virtual.
(ii) It is erect.
(iii) It is same in size.
(iv) It is at same distance from the mirror as the distance of an object from the mirror.

The red pigment (haemoglobin) present in the red blood cells of the blood makes the blood look red. The haemoglobin carries oxygen and transports it to all the parts of the body.

The process of respiration which takes place in the absence of oxygen is called anaerobic respiration. In this process, glucose (food) is broken down into alcohol or lactic acid, carbon dioxide and energy. The organisms that can survive in the absence of air are called anaerobes like yeast.
Glucose\(\xrightarrow[of\ CO_2]{absence}\) Alcohol + CO₂ + Energy.

Materials which do not allow heat to pass through them easily are poor conductors of heat and are called insulators. e.g., wood, plastic.

If the filament of the bulb is broken, the circuit will not be complete.
So, the bulb will not glow.

The devices that work on the basis of magnetic effects of current are loudspeaker and electric bell.

When a pan is removed from the fire, it loses heat to the surroundings by radiation and it cools down.

(a) Spirogyra - fragmentation
(b) Yeast - budding
(c) Money plant - Vegetative propagation.

Diaphragm is known as the floor of chest cavity

During aerobic respiration, carbon dioxide and water are released along with a large amount of energy.
\(glucose\overset { { O }_{ 2 } }{ \longrightarrow } { O }_{ 2 }+water+Energy\)

Yes, the image formed by the plane mirror is always upright.

The circulatory system consists of three major organs, i.e., blood, blood vessels and heart.

A cockroach has small opening on the side of its body. These openings are called spiracles. Insects have a network or air tubes called tracheae for gas exchange, oxygen rich air rushes through spiracles into the tracheal tubes, diffuses into the body tissues and reaches every cell of the body. Similarly carbon dioxide from the cells goes into the tracheal tubes and moves out through spiracles. These air tubes or tracheae are found only in insects

At sea-shore during the day cold air from the sea moves towards the beach because the land gets more heated than the sea water. Hot air above the land rises up, and cold air from the sea moves towards the land beach. This is called sea breeze as shown in fig. (a).
During the night, cold air from the land moves towards the sea because the land cools more quickly than the sea water. So hot air above the sea rises up and cold air from the land moves towards the sea. This is called land breeze as shown in fig.(b).
       

(a) Asexual reproduction is a type of reproduction in plants in which new plants are obtained from old ones without the production of seeds.
Two methods of asexual reproduction:
Vegetative Production, Spore Formation, Budding, Fragmentation (any two).
(b) Reproductive Parts of Flower:

Electric bell consists of an iron hammer around which a wire is wound. When current is passed by pressing the button, the wire turns into a temporary magnet. The hammer is attracted towards gong to make sound. When this strikes, the current is disconnected automatically. It happens due to shift arrangement in it. The magnetic property of wire is lost and it comes back to its original position through a spring. In this way, we get separated hammering, resulting in ringing of an electric bell

Blood is a fluid which flows in blood vessels.
(a) Functions of blood :
(i) It transports digested food from small intestine to all parts of the body. 
(ii) It carries oxygen from lungs to cell.
(b) Components of blood:
(i) Fluid: Plasma
(ii) Cells: RBC,WBC, Platelets.