Excretion To Maintain Homeostasis Kerala Syllabus 9th Question 1.
How can make our external environment garbage-free?
Answer:
We can made our external environment garbage free by processing reusing or recycling waste material.
Kerala Syllabus 9th Standard Biology Notes Chapter 5 Question 2.
Different by-products are formed as a result of many …. in the cells.
Answer:
Metabolic activities
Excretion To Maintain Homeostasis Notes Kerala Syllabus Question 3.
What are the main excretory products in human beings?
Answer:
Carbon dioxide, water, and nitrogenous compounds.
Kerala Syllabus 9th Standard Biology Notes Question 4.
………. carries excretory products to excretory compounds.
Answer:
Blood
9th Class Biology Chapter 5 Notes Kerala Syllabus Question 5.
Complete the flow chart of the waste materials formed inside the cells reach excretory organs?
Answer:
a) Tissue fluid
b) Blood
Excretory Organs
9th Standard Biology Notes Kerala Syllabus Question 6.
Name the organs that help to remove waste materials from blood and maintain homeostasis?
Answer:
Liver, Lungs, skin, and kidney
9th Class Biology 5th Lesson Questions And Answers Question 7.
Complete the illustration.
Answer:
Liver – The Waste Processing Unit
Class 9 Biology Kerala Syllabus Question 8.
What is the function of liver?
Answer:
Liver converts harmful substances entering the body and those produced inside the body into harmless substances. Synthesis of urea from ammonia is an example for this.
9 Biology Kerala Syllabus Question 9.
…………….. are formed by the breakdown of protein.
Answer:
Amino acids
9th Standard Biology Solutions Question 10.
What are the uses of amino acids?
Answer:
Amino acids are used for the synthesis of various substances like proteins, enzymes etc. which are used for bodybuilding.
Class 9 Biology Solutions Kerala Syllabus Question 11.
What is the most harmful by-product formed by the metabolism of amino acid?
Answer:
Ammonia
9th Class Biology Chapter 5 Kerala Syllabus Question 12.
Prepare a note on the synthesis of urea.
Answer:
Amino acids are formed by the breakdown of proteins. As a result of the metabolic activities of amino acids, several nitrogenous by-products are formed. The most harmful among these is ammonia. The ammonia formed in tissues diffuses into blood through tissue fluids and blood transports it to the liver. In liver with the help of certain enzymes, ammonia combines with carbon dioxide and water to form urea.
9th Class Biology Notes Question 13.
Write down the chemical equation of the synthesis of urea.
Ammonia + carbon dioxide + water → urea
Formation Of Sweat
9th Biology Kerala Syllabus Question 14.
How is sweat formed from blood?
Answer:
Blood passes through the capillaries excess water and minerals enter the sweat glands. This is eliminated as sweat through the body surface.
9th Biology Notes Kerala Syllabus Question 15.
What are the components of sweat?
Answer:
Urea, salt, and water
Biology 9th Class Chapter 5 Notes Kerala Syllabus Question 16.
Which is the largest organ in our body?
Answer:
Skin
9th Biology Notes Question 17.
What do you mean by sweat gland?
Answer:
Sweat gland is a long coiled tube that opens to the surface of the skin.
9th Standard Biology Guide Question 18.
The lower portion of the sweat gland is rich in
Answer:
Capillaries
Biology 9th Kerala Syllabus Question 19.
……… helps in regulating our body temperature.
Answer:
Sweating
Kidneys
9 Biology Kerala Syllabus Question 20.
What are the main functions of kidney?
Answer:
Kidneys are vital organs which help in maintaining homeostasis by filtering waste products like urea, salts, vitamins, other harmful substances, etc. from blood. When blood passes through the kidneys, the waste materials present in it are filtered.
Question 21.
Prepare a short note on the position and size of the kidney?
Answer:
Human beings possess a pair of kidneys, situated on both sides of the vertebral column adjoining the muscles in the abdominal cavity. They are bean-shaped and are about 11 cm long, 5 cm broad and 3 cm thick. Each kidney is covered by a strong but soft membrane.
Question 22.
Illustrate kidney and its parts.
Answer:
Question 23.
Complete the illustration of kidneys and associated parts.
Answer:
a) bean-shaped and are located in the abdominal cavity on either side of the vertebral column.
b) Renal artery
c) Renal vein
d) Ureters
Internal Structure of Kidney
Question 24.
Internal structure of kidney
Answer:
Question 25.
Analyze illustration given below and prepare table including the parts and peculiarities of nephron.
Answer:
| Parts | Peculiarities |
| Bowman’s capsule | The double-walled cupshaped structure at one end of the nephron. The space between the two walls is called capsular space. |
| Afferent vessel | The branch of renal artery which enters the Bowmann’s capsule. |
| Glomerulus | The region where afferent vessel enters the Bowmann’s capsule and splits into minute capillaries. |
| Efferent vessel | The blood vessel that comes out of Bowman’s capsule. |
| Peritubular capillaries | Blood capillaries seen around the renal tubules as the continuation of the efferent vessel. |
| Renal tubule | The long tubule which connects the Bowman’s capsule and the collecting duct. |
| Collecting duct | The part where renal tubules enter. Absorption of water takes place. Urine is collected and is carried to the pelvis. |
Question 26.
……… are the structural and functional units of kidneys.
Answer:
Nephrons
Question 27.
Where is Bowmann’s Capsule of nephrons distributed?
Answer:
Cortex
Question 28.
What is capsular space?
Answer:
It is the space between the double walls of the Bowman’s capsule.
Question 29.
Blood capillaries seen around the renal tubules as continuation of the efferent vessel are ………..
Answer:
Peritubular capillaries
Question 30.
………… helps the ultrafiltration.
Answer:
Glomerulus
Formation of urine
Question 31.
List out the process of formation of urine.
Answer:
- Ultrafiltration
- Reabsorption and secretion
- Absorption of water
Question 32.
What are the characteristic that help in ultrafiltration?
Answer:
This process is supported by the high pressure developed in the glomerulus, due to the difference in the diameter of afferent vessel and efferent vessel
Question 33.
How is urine formed?
Answer:
When blood flows through the glomerulus, ultrafiltration takes place through its small pores. The glomerular filtrate formed as a result of this is collected in the capsular space. When glomerular filtrate flows through renal tubeless to the collecting duct, essential components are reabsorbed to the peritubular capillaries. The absorption of excess water from the glomerular filtrate takes place in the collecting duct. What is left behind is urine.
Question 34.
Prepare a table relating to the different components of the glomerular filtrate and urine.
Answer:
| Components of glomerular filtrate | Components of urine |
| Water | Water-96% |
| Glucose | Urea-2% |
| Amino acids | Sodium chloride |
| Sodium, potassium | Potassium chloride |
| calcium ions, vitamins | Calcium salts |
| Urea, uric acid creatinine, etc | Phosphate, Uric acid |
| Creatinine etc. – 2% |
Question 35.
Urine is temporarily stored in the
Answer:
Urinary bladder
Question 36.
State whether true or false
Washing out of germs inside the urinary tract also
takes place during the process of micturition.
Answer:
True
Question 37.
How does avoiding timely urination affect our body and list out the healthy habits to be followed?
Answer:
Avoiding urination for a long time prevents the expulsion of bacteria that may be present in the urinary tract and urinary bladder. This causes infection in the inner membrane of the urinary bladder.
Females are more susceptible to urinary tract infections when compared to males.
1) Frequent urination
2) Drink plenty of water
3) Keep the personal hygiene
Question 38.
Prepare a flow chart on the role of kidneys in maintaining homeostasis
Answer:
Kidney Diseases
| Disease | Reason | Symptoms |
| Nephritis | inflammation of kidneys due to infection or intoxication. | Turbid and dark-colored mine, back pain, fever, oedema on face and ankle |
| Kidney stone | Deposition of crystals of calcium salts in kidney or urinary tract. | Pain in the lower abdomen, blockage of mine, dizziness, vomiting |
| Uremia | Different types of kidney diseases, nephritis. diabetes. Irigli’s blood pressure. | Anemia, loss ol body weight, dizziness suffocation, dianitoea production of urine stops gradually. |
Haemodialysis
Question 39.
What do you mean by hemodialysis?
Answer:
Haemodialysis is the process proposed by modern medicine for the removal of wastes from the blood when both the kidneys become non-functional. In this process, blood is pumped into an artificial kidney called haemodialyser and is purified.
Question 40.
Who designed the first artificial kidney?
Answer:
William Johann Kolff in 1944.
Kidney Transplantation
When both kidneys of an individual get damaged completely a fully functioning kidney should be received from a donor to save life. Kidney of a healthy person who died in an accident or of a completely healthy person can be transplanted after considering the matching of blood groups and tissues.
Excretion In Other Organisms
Diversity in Excretion:
Question 41.
Prepare a table about the excretory organs and excretory products of different organisms?
Answer:
| Organism | Excretory product | Excretory organ |
| Amoeba | Ammonia, excess water in the body | No special excretory organ, contractile vacuoles function as excretory organs. |
| Earthworm | Urea, ammonia, water | Special structures called nephridia collect excretory products from body cavity and eliminate through pores in the body surface. |
| Insects | Uric acid | Malpighian tubules seen along with digestive tract. They separate excretory products and eliminates along with digestive wastes. |
| Fishes | Ammonia | Kidneys filter the wastes and eliminate directly to water |
| Frog | Urea | Nitrogenous wastes filtered by kidneys are excreted in the form of urine. |
| Reptiles and birds | Uric acid | Kidneys filter waste products and eliminate along with digestive wastes. |
Question 42.
What are the methods of the excretion in plants?
Answer:
Stomata, hydathodes, formation of heartwood, abscision of leaves.
Question 43.
Illustration related to the excretion in plants.
Answer:
Let Us Assess
Question 1.
Glucose, amino acids, etc. found in the glomerular filtrate are absent in urine. Why?
Answer:
When glomerular filtrate flows through renal tubules to the collecting duct, essential components are reabsorbed to the peritubular capillaries. So glucose and amino acids are absent in urine.
Question 2.
The steps involved in the formation of urine are given below. Arrange them in the correct sequence.
1. Collects urine
2. Ultrafiltration takes place
3. Reabsorption of ions takes place towards this part from renal tubules.
4. Collects glomerular filtrate
5. Excess urea is secreted here from peritubular capillaries.
Answer:
Question 3.
Alcoholism is a bad habit which should be avoided. Analyze this statement relating it to the health of liver.
Answer:
The detoxification of alcohol in our body is done by liver cells. As a result liver cell become damaged.
Question 4.
Based on the similarities in major excretory materials, arrange the following organisms properly in the table given below
Frog, Amoeba, Human beings, Fish, Birds, Insects
Answer:
| Ammonia | Urea | Uric acid |
| Amoeba | Frog | Birds |
| Fish | Human | Insects |
Question 5.
Observe the figure and answer the questions.
Answer:
a) A) Afferent vessel
B) Efferent vessel
b) When blood flows through the glomerulus, ultrafiltration takes place through its small pores. This process is supported by the high pressure developed.in the glomerulus, due to the difference in the diameters of afferent versel and efferent vessel.
