Human Digestive System
The human digestive system consists of an alimentary canal and associated glands.
The alimentary canal starts with an anterior mouth and ends with the posterior anus.
The alimentary canal consists of a mouth, oral cavity, pharynx, oesophagus, stomach, duodenum, small intestine, large intestine, rectum and anus.
Salivary glands, liver, pancreas are the associated glands help in digestion.
The Human Heart
The heart is a muscular organ that helps to pump blood to the various tissues of our body. The heart has different chambers to prevent the mixing of oxygenated and de-oxygenated blood. The upper chambers of the heart are called atria and the lower chambers of the heart are called ventricles. The walls of ventricles are thicker than the walls of atria because to pump blood to various parts.
Human Excretory System
The Excretory system of human beings includes a pair of kidneys, a pair of ureters, a urinary bladder, and a urethra.
Kidneys are located in the lower abdominal cavity, one on either side of the backbone. Urine produced in the kidneys passes through the ureters into the urinary bladder where it is stored until it is released through the urethra.
Each kidney consists of millions of filtrating units called nephrons.
A nephron is a functional unit of the kidney. It has two parts, namely, glomerulus and renal tubules. The glomerulus is a tuft of blood capillaries present in side a cup-like structure called Bowman's capsule. The renal tubule consists of Bowman's capsule, proximal and distal convoluted tubules, Henle's loop, and collecting tubule.
Cross-section of Leaf
The leaf is a kitchen of the plant body where photosynthesis is occurring. A cross-section of the leaf shows the presence of green dots inside the cell are called chloroplasts which contain chlorophyll. The upper and lower epidermis covers the mesophyll. The mesophyll is differentiated into spongy and palisade parenchyma in dicotyledonous leaves. The epidermis is provided with small openings called stomata.
Structure of Stomata
Stomata are the tiny pores present on the surface leaves. Help in transpiration (evaporative loss of water) and gaseous exchange. Each stoma is made up of bean-shaped guard cells, they help in opening and closing the stomatal pore. Guard cells are covered by subsidiary cells.
The Human Brain
The human brain is a part of the central nervous system. The human brain has three divisions, namely, fore-brain, mid-brain, and hind-brain.
Fore-brain- Consists cerebrum (a large part of the brain), and diencephalon (thalamus and hypothalamus). Mid-brain- Consists limbic system and acts as a bridge between fore-brain and hind-brain.Hind-brain- Consists cerebellum (maintains body balance), pons (regulates mastication, respiration, and facial expression), and medulla oblongata (regulates most of the involuntary activities).
The flower is a reproductive organ of angiosperm plants. Floral parts are arranged in four different whorls. They are calyx, corolla, androecium, and gynoecium. Stamens and carpels are the male and female reproductive structures of a flower respectively.
Germination of Pollen on Stamen
After the pollen lands on the suitable stigma, it has to reach the female germ cells which are in the ovary. For this, a tube grows out of the pollen grain and travels through the style to reach the ovary.
Male Reproductive System of Human
The male reproductive system consists of;
Primary sex organs: a pair of testes.
Accessory ducts: Epididymis, vas deferens, urethra.
Accessory glands: Seminal vesicles, prostate glands, and bulbourethral gland.
External genitalia: A penis.
Female Reproductive System of Human
The female reproductive system consists of;
Primary sex organs: a pair of ovaries.
Accessory ducts: fallopian tubes, uterus, cervix, and vagina.
Accessory glands: mammary glands.
External genitalia: vulva.
Diagrams perform an important role in biology.
They help to remember the whole concept. Practice well along with lables.
Regeneration in Planaria
The process in which new individual organisms are produced by the parental body parts. That is, if the individual is somehow cut or broken up into many pieces, many of these pieces grow into separate individuals.
Electrolysis of Water
Electrolysis of water is the process of using electricity to decompose water into oxygen and hydrogen gas by a process called electrolysis.
Water is electrolyzed to give H2 gas at one electrode and O2 gas at the other electrode.
Thus, two molecules of water on electrolysis give 2 molecules of hydrogen gas and one molecule of oxygen gas or the amount of hydrogen gas collected would be double that of oxygen gas.
Reaction of zinc granules with dilute sulphuric acid
When zinc granules are added to dilute sulphuric acid, there is effervescence on the surface of zinc granules. When the gas being evolved is passed through the soap solution, the H2 gas evolved gets trapped in the soap solution forming bubbles.
Once we take a burning candle near a gas-filled bubble, gas bubbles break up with a pop sound due to the burning of hydrogen gas.
Electrolytic Refining of Copper
Many metals like copper, nickel, silver, etc., are refined by this method.
The impure copper metal is made the anode of an electrolytic cell. The cathode is made of a thin pure copper plate.
On passing direct current through the copper suphate solution, copper is dissolved from the anode and deposited on the cathode. The impurities collected at the bottom below the anode which are known as anode mud.
Acid solution in water conducts electricity
This experimental setup concludes an acid solution conducts electricity. Acids are good conductors of electricity.
When a direct current is passed through dilute hydrochloric acid, it dissociates into ions (H+ and Cl-). These ions conduct electricity in the water and the bulb connected to a circute glows.