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Class 10 Chemistry Chapter 25 Biochemistry Class Test 4 PDF | Punjab Board 2027 Model Papers
Chemistry 10th Class Chapter 25 Biochemistry Test 4
Class 10 Chemistry Chapter 25 Biochemistry Class Test 4 PDF is part of the Punjab Board 2027 Model Papers series, prepared according to the new syllabus issued by PECTAA Punjab. Students can use this chapter-wise test to prepare for the Class 10 Chemistry examination, revise important concepts from Chapter 25: Biochemistry, and practise questions from the full unit, including the exercise. This test is designed to support systematic exam preparation through a chapter-wise test series for the 2027 board examinations.
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Chapter: 25
Total Time: 35 min
(Test # 4)
Chemistry
Total Marks: 25
ABCD
1ABCD
2ABCD
3ABCD
ABCD
4ABCD
5ABCD
6ABCD
ABCD
7ABCD
8ABCD
NOTE:Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink. Cutting or filling two or more circles will result in zero mark in that question.
Q.1:(08)
1.
Which functional groups react to produce a peptide linkage in proteins?
(A) Carboxyl group and hydroxyl group
(B) Carboxyl group and amino group
(C) Hydroxyl group and amino group
(D) Ester group and amino group
Answer: (B). The –COOH group of one amino acid reacts with the –NH2 group of another, losing water to form the peptide bond (–CO–NH–).
2.
Palmitic acid is found in:
(A) Coconut oil
(B) Animal fat
(C) Palm oil
(D) Olive oil
Answer: (C) Palm oil. Palmitic acid (C15H31COOH) gets its name from palm oil.
3.
The first discovered vitamin was an amine so they were named:
(A) Bio-amines
(B) Vital amines or vitamins
(C) Organic amines
(D) Chemical amines
Answer: (B). Funk named them “vital amines”, which was shortened to vitamins.
4.
The test performed to detect cancer in early stages is:
(A) Genetic test
(B) Urine test
(C) Galleri test
(D) Electrolyte test
Answer: (C) Galleri test (a blood test that screens for many cancers at early stages).
5.
DNA molecules are mostly found in:
(A) Cytoplasm
(B) Cell membrane
(C) Nucleus of cells
(D) Mitochondria
Answer: (C) Nucleus of cells.
6.
Blood tests give important information about how well which organs are working?
(A) Heart and lungs only
(B) Kidneys, liver and other organs
(C) Bones and muscles only
(D) Eyes and ears only
Answer: (B). Blood tests such as liver and kidney function tests show how well these organs work.
7.
Fatigue and depression are caused by deficiency of:
(A) Vitamin A
(B) Vitamin C
(C) Vitamin D
(D) Vitamin B1
Answer: (D) Vitamin B1 (thiamine). Its deficiency causes fatigue, irritability, depression and, in severe cases, beriberi. (Check your textbook/teacher key, since low vitamin D can also cause tiredness.)
8.
In gene therapy, doctors fix a faulty gene or replace it with:
(A) A chemical compound
(B) A healthy gene
(C) A protein
(D) A carbohydrate
Answer: (B) A healthy gene.
(PART – I)
Q.2 Write short answers to following questions.(6×2=12)
i.
What is the role of enzymes in our body?
Ans: Enzymes are protein catalysts. They speed up biochemical reactions such as digestion and metabolism, work under mild conditions (body temperature) and are highly specific, so life processes can occur fast enough.
ii.
What is the role of lipids in our body?
Ans: Lipids are a concentrated source of energy (about 9 kcal/g), act as an energy store, insulate and protect organs, form cell membranes and carry fat-soluble vitamins (A, D, E, K).
iii.
Which commercial products are obtained from oils and fats?
Ans: Soap, glycerol, candles, margarine and vanaspati ghee, paints and varnishes, cosmetics and biodiesel.
iv.
What is genetic enginering?
Ans: Genetic engineering is the deliberate change of an organism’s genetic material (DNA) by inserting, removing or modifying genes to give it new, useful characteristics, e.g. production of insulin by bacteria.
v.
Write down the names of two polymeric carbohydrates.
Ans: Starch and cellulose (glycogen is another example).
vi.
How does cloning differ from genetic engineering?
Ans: Cloning makes an exact genetic copy of an organism or gene without changing the DNA. Genetic engineering changes the DNA by adding, removing or altering genes.
(PART – II)
Note: Attempt the following question.
Q.3: Write functions of carbohydrates and lipids in our body.(5)
Functions of carbohydrates:
- Main source of energy (about 4 kcal/g); glucose fuels the brain and muscles.
- Stored as glycogen in liver and muscles, to be used when needed.
- Cellulose (dietary fibre) helps digestion and bowel movement.
- Ribose and deoxyribose are parts of RNA and DNA.
- Concentrated source and long-term store of energy (about 9 kcal/g).
- Build cell membranes (phospholipids) and make some hormones (steroids).
- Insulate the body against heat loss and protect delicate organs.
- Help absorb and carry fat-soluble vitamins A, D, E and K.
