General Science|| Chapter 2: Cell Structure and Function for Competitive Exam.

                 

          

✅Prepared by : Elisa Lalrinngheta (Zo Guide Founder)  

@Copyright Reserved by the author 

                          📝Chapter 2: Cell

Bibliography: He chapter Cell Structure and Function hi Class 8,10,12( NCERT) Zirlai bu atanga lak khawm ani a Competitive exam na a pawimawh thei tur ang ber leh lo chhuak thin te highlights ani bawk..

Introduction : Biology-ah chuan, cell  chu nunna nei zawng zawngte pianphung (structure) leh chetzia (function)  innghahna bul ani.

✅Types of Cell: Plant leh Animal cell-te hi thil nung (living organisms) zawng zawng innghahna bulpui, cell (thahrui/thapui) hmanga siam an ni. Eukaryotic cell an nih avangin nucleus leh cell organelle chi hrang hrang an nei ve ve a, mahse a pianphung leh hna thawhah an danglam hle. 

                             1.Plant Cell: 

✅Pianphung: A lian zawk a, a rectangular emaw, fixed shape a nei.

✅Cell Wall: Cell membrane pawn lamah cellulose-in a siam, "Cell wall" hruinghet tha tak a awm, a hmun nghetah a vuan reng.

✅Chloroplast: Ni zung hmanga eitur insiamna (photosynthesis) a awm avangin a hring a ni.

✅Vacuole: Vacuole lian tak, a laiah a awm. 

                   2.Animal Cell (Rannung Cell):

✅Pianphung: A te zawk a, a rual lo (irregular) emaw, a zung (round) hmel a ni.

✅Cell Wall: Cell wall a awm lo, cell membrane chauh a awm.

✅Chloroplast: Chloroplast a awm lo, eitur an insiam thei lo.

✅Vacuole: Vacuole a te hle, a tam pawh a tam thei. 

➡️A Tlangpui (Summary):

✅Siamtu: Plant cell-in cell wall a nei a, animal cell-in a nei lo.

✅Eitur: Plant cell-in chloroplast hmangin eitur an siam a (autotrophs), animal cell-in eitur dang an rinchhan (heterotrophs).

Common: Nucleus, cytoplasm, leh mitochondria chu an pahnih hian an nei ve ve. 

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📝Discovery of Cell ( Cell an lo hmuhchhuah dan leh hmu chhuak tu te):  Cell hi biology-a bulpui ber a ni a, hemi hmuhchhuah hian biology leh medicine-ah hmasawnna nasa tak a thlen.

✅Cell Hmuhchhuah Dan (History):

1. 1665: Robert Hooke

    - English scientist Robert Hooke chuan microscope hmangin cork (cork tree) a en a, a structure a hmuh chu "cell" (Latin: cellula = room) tiin a vuah.

    - Cork hi cell wall aṭanga siam a ni a, cell a hmuh hi thi tawh (dead cell) a ni.

2. Antonie van Leeuwenhoek (1632-1723):

    - Dutch scientist Antonie van Leeuwenhoek chuan microscope ṭha zawk hmangin amoeba, bacteria, leh red blood cell te a hmuh chhuak.

    - "Father of Microbiology" tiin an vuah.

3. 1839: Cell Theory:

    - Theodor Schwann (German zoologist) leh Matthias Jakob Schleiden (German botanist) te chuan _Cell Theory_ an siam:

        1. Organism zawng zawng cell-a siam an ni.

        2. Cell hi life unit a ni.

        3. Cell thar chu cell hmasa aṭanga lo chhuak a ni (Rudolf Virchow, 1858-ah a belh).

✅Cell Pawimawhna:

1. Life Unit:

    - Cell hi life unit a ni a, an ṭhat chuan organism a ṭha.

2. Medicine leh Research:

    - Cell study (cytology) hian cancer, genetic disorder, leh vaccine siamnaah hmasawnna a thlen.

3. Genetic Information:

    - DNA (genetic material) chu cell nucleus-ah a awm a, organism siam dan tur a keng.

        Kum 1940-a electron microscope an hmuh chhuah khan, cell-te leh a bung hrang hrangte (organelles) awmze thuk tak hmuh theih leh hriat theih a lo ni ta a.A hmasa in Cell pianphung or structure hi lo en hmasa ila:

✅Function of Cell: 

1.Plasma Membrane or Cell Membrane:

1).Cell membrane is also called the plasma membrane. (Cell membrane hi plasma membrane an ti bawk.)

2).It can be observed only through an electron microscope. (Electron microscope hmang chauhva hmuh theih a ni.)

3).Plasma membrane is the outermost covering of the cell that separates the contents of the cell from its external environment. (Plasma membrane hi cell pawnlang ber tuamtu a ni a, cell chhunga thil awmte chu a pawn atmosphere atangin a then hrang.)

2.Endocytosis

1) Plasma membrane hi a in thlep thei a, organic molecule lipids leh proteins an tih atanga siam an ni.

2) Cell membrane inthleh(flexible ) theihna hian cell chhungah chaw leh thil dang, a pawn lam atangin a la lut thei bawk. Heng thil thlengte hi endocytosis (endo - chhung lam; cyto - cell) an ti. Amoeba-in a chaw a lak luh dan pawh hetiang hi a ni.

3.Diffusion (Thehdarh):

1) Plasma membrane hi thil thenkhat chauh kaltlang theihna membrane a ni [Plasma membrane hi a pawr a, thil eng emaw (substances or materials) chhung lam leh pawn lamah a kaltlang tir thei ve ve].

2) Thil thenkhat, carbon dioxide emaw oxygen emaw ang chi chu cell membrane kaltlangin diffusion tih hmangin an che thei [thil thenkhat (substance) concentration san na hmun atanga concentration hniam na hmun (hypotonic solution) pana a chetna].

3) Chuvangin, diffusion hian cell te inkarah leh cell leh a chhehvel inkarah gas inthleng tawn turin hmun pawimawh tak a luah.

3.Osmosis (Tui thehdarh):

1) Tui pawhin diffusion dan a zawm ve tho. Tui molecules inthil thenkhat chauh kaltlang theihna membrane a kaltlang hi osmosis an ti.

2) Osmosis chu tui concentration san na hmun atanga semi-permeable membrane kaltlanga tui concentration hniam na hmun pana tui kal hi a ni. 

Chuvangin, osmosis hi semi-permeable membrane kaltlanga diffusion a thlen dan special case a ni.

3) Unicellular freshwater organisms leh plant cell tam zawk chuan osmosis hmangin tui an la lut thin. Plant root in tui a hip luh dan pawh osmosis entirna a ni.

4) Chuvangin, diffusion hi cell nunna atan gas leh tui inthleng tawn turin a pawimawh hle. Heng bakah hian, cell chuan a chhehvel atangin nutrition a la lut bawk.

5) Molecules hrang hrang chu energy (ATP) mamawh chi transport hmangin cell chhung leh pawnah an che thin.

4.Reverse Osmosis (RO)

✅Reverse osmosis (RO) hi tui tihthianghlimna technology pakhat niin, semipermeable membrane hmangin tui in tur atanga thil lian zawk (larger particles) a paih chhuak thin.

➡️ osmotic pressure chu a hneh thin.

➡️ Reverse Osmosis chu thil thleng a ni a, tui thianghlim, diluted solution [hypotonic] atangin semi permeable membrane kaltlangin concentrated solution [hypertonic] lamah a luang thin.

➡️ Semi permeable tih awmzia chu, membrane chuan molecules te leh ions te chu a kaltlang tir anga, mahse molecules lian zawk emaw, dissolved substances lian zawk tan chuan a dang ang.

5.Cell wall 🧱 

➡️ Cell wall hi ramsa (animals ) ah chuan a awm lo.

➡️Plant cells-ah chuan, plasma membrane bakah, pawn lama covering nghet tak, cell wall an tih chu a awm bawk. Cell wall hi plasma membrane pawn lama awm a ni.

➡️ Plant cell wall hi a tam zawk chu cellulose atanga siam a ni. Cellulose hi substance complex tak a ni a, plant te chu structural strength a pe thin.

6.Plasmolysis

         Plant cell nungin osmosis kaltlangin tui a chan chuan, cell chhung te chu an chuar emaw, an inhnit khawm emaw thin a, cell wall atangin an hla hret thin. He thil thleng hi plasmolysis (plasma fluid, lysis disintegration, decomposition) an ti.

Cell nung chauhvin, cell thi nilovin, osmosis hmangin tui an hip thei. Cell wall-in plant, fungi leh bacteria cells te chu pawn lama media dilute tak [hypotonic external media] ah pawh chuar lovin an awm thei a ni.

         Chutiang media-ah chuan, cell te chuan osmosis hmangin tui an hip duh thin. Cell chu a chuar a, cell wall chu pressure a siam sak thin. Wall chuan pressure intluk chiah, cell chuar lamah chuan a siam let ve bawk thin. 

➡️Cell wall chuan cells te chu hypertonic medium (medium of high concentration) in a hual velah pawh puak lo turin a veng bawk thin.

➡️ Chutiang media-ah chuan, cell te chuan osmosis hmangin tui an hmu duh thin. Cell chu a vung a, cell wall chu pressure a siam sak thin. Wall chuan pressure intluk chiah, cell vung lamah chuan a siam let ve bawk thin.

➡️ An wall an neih vangin, plant cells te chuan an vel a medium inthlak danglam nasa zawk chu ran cells aiin an tuar thei zawk.

7.Cytoplasm

✅ Jelly ang mai a awm, cell membrane leh nucleus inkar a awm substance chu a ni.

✅ Cytoplasm chu plasma membrane chhunga tui a ni.

✅Cell organelle hrang hrang [mitochondria, golgi bodies, ribosomes, etc] pawh a awm bawk.

✅Heng organelle pakhat theuh hian cell tan hna bik an thawk theuh a ni.

✅Cell organelle-te hi membrane-in a tuam vek a ni.

✅Membrane pawimawhna hi virus entirna hmangin hrilhfiah theih a ni.

✅Virus-ah hian membrane a awm lo a, chuvangin, an taksa chhunga cell machinery hmanga an inthawh theih nan, taksa nung an luh chilh hma chuan nunna an lantir lo.

8.Nucleus

        Cell nung pakhat pawimawh tak a ni.

A tlangpuiin a round a, cell laili takah a awm thin.

Stain theih a ni a, microscope hmangin awlsam takin hmuh theih a ni.

✅Nucleus hi cytoplasm lakah nuclear membrane an tih, double layered membrane hmanga theh hrana awm a ni.

✅He membrane hi a porous bawk a, cytoplasm leh nucleus chhunga thil awmte inkara insawn theihna a pe [diffusion].

✅ Microscope high magnification hmangin, nucleus chhunga thil round(mum /bial)  te zawk kan hmu thei a, chu chu nucleolus an ti.

✅ Chu bakah, nucleus-ah hian thread ang deuhva inzar, chromosome an tih a awm. Heng hian gene an keng a, gene chu nu leh pate atanga fate leh tuchhuan thlenga nunphung leh mizia landan keng tu pawimawh tak ani. 

✅Nucleus hian gene transfer a mawhphurhna bakah, cell hna thawh zawng zawng control center angin hna a thawk.

✅Cell nung chhunga thil awm zawng zawng hi protoplasm [cytoplasm + nucleus] an ti. Hei hian cytoplasm leh nucleus a huam vek a ni. 

✅Protoplasm hi cell thil nung an ti.

Bacteria cell nucleus hi multicellular organism cell ang maia felfai taka inorganize a ni lo. Nuclear membrane a awm lo.

         Cell tin hian a chhunga thil awmte leh pawn lam boruak tihdanglam theih nan a velah membrane a nei vek a ni.

Cell lian leh inthlâk danglam thei, multicellular organism cell te pawh telin, an structure leh function inthlâk danglam tak tak tura an mamawh chemical activities tam tak a awm a ni.

Hêng activities hrang hrangte hi an inthliár hrang theih nan, hêng cell te hian an chhûngah membrane-bound little structures (or 'organelles') an hmang a ni.

9.Chromosomes

✅Nucleus chuan chromosomes a keng a, chu chu cell a insem dâwn chauhvin rod-shaped structures angin a hmuh theih a ni.

✅ Chromosomes hian nu leh pate aṭanga chhuan thar lo awm tura feature rochun tura information chu DNA (deoxyribo nucleic acid) molecules hmangin a keng a ni.

✅ Chromosomes hi DNA leh Protein aṭanga siam a ni.

✅ DNA molecules hian cell siam leh organize tura information mamawh a keng a ni. DNA functional segments te chu genes an vuah a ni.

Cell a insem loh hian, he DNA hi chromatin material pêng pakhat angin a awm a ni. 

✅Chromatin material hi thread (lazai inzial ang) ang maia inphuar khawm angin a hmuh theih a ni. 

➡️Cell a insem dâwn apiangin, chromatin material hi chromosomes ah a insiam ṭhin a ni.

✅Nucleus hian cellular reproduction-ah mawhphurhna pawimawh tak a chelh a, chu chu cell pakhatin cell thar pahnih a siam theihna process a ni.

✅Pawn lam boruak nên an inzawm khawm a, cell chu engtin nge a thang chhoh ang a, a puitlin hunah eng form nge a lan ang tih hrilhfiah nan mawhphurhna pawimawh tak a chelh bawk a, chu chu cell chemical activities hrilhfiahna a ni.

📝Prokaryotic Cells vs. Eukaryotic Cells

✅Organisms, an cell-ah nuclear membrane awm lote chu prokaryotes (pro - primitive or primary, karyote = karyon = nucleus) an vuah a ni.

✅ Organisms, an cell-ah nuclear membrane awmte chu eukaryotes an vuah a ni.

✅Prokaryotic cell-ah pawh hian eukaryotic cell-a awm cytoplasmic organelles dang tam tak a awm lo bawk a ni.

10.Nucleoid:

Bacteria ang organism thenkhat ah chuan, nuclear membrane a awm loh avangin cell-a nuclear region chu a fiah lo thei a. Chutiang nuclear region fiah lo, nucleic acid chauh awmna chu nucleoid an ti.

11.Vacuoles:

Cytoplasm chhunga awm bungrua ruak chu vacuole an ti. Onion cell (plant cell) angah chuan pakhat lian tak a awm thei a. Cheek cell (animal cell) ah chuan vacuole te zawk a awm.

✅Vacuole lian chu plant cell ah a tam hle. Animal cell a vacuole te chu a te zawk daih.

➡️ Vacuole chu solid emaw liquid emaw dahkhawlna ip (storage sacs) a ni.

✅Plant cell thenkhat a central vacuole chu cell volume 50-90% a ni thei.

✅Plant cell a vacuole chu cell sap in a khat a, turgidity (a puar/lian) leh rigidity (a nghet) a pe a ni.

✅Plant cell nunna atana pawimawh thil tam tak chu vacuole ah hian dahkhawl a ni. Chungte chu amino acid, sugar, organic acid hrang hrang leh protein thenkhat te an ni.

✅ Amoeba ang single-celled organism ah chuan, food vacuole ah hian amoeba in a ei tawh food item te chu a awm.

✅ Unicellular organism thenkhat ah chuan, specialized vacuole te hian tui tam lutuk leh waste thenkhat cell atanga paihchhuah ah pawh hian hna pawimawh tak an thawk.

12.Endoplasmic Reticulum (ER):

        Endoplasmic reticulum (ER) chu membrane in tuam, tube leh sheet lian tak network a ni. Tubule thui tak emaw, bag round emaw thui tak (vesicles) ang a lang.

✅ ER membrane chu structure ah plasma membrane nen a inang.

✅ ER chi hnih a awm - rough endoplasmic reticulum (RER) leh smooth endoplasmic reticulum (SER).

✅ RER hi microscope hnuaiah chuan a hmulhmul deuh hleka a lan chhan chu a chung a particles, ribosomes an tih te chu a bet thin vang a ni.

✅ Ribosomes te hi cell tinrenga awm a ni a, protein siamchhuahna hmunpui ber a ni.

✅ Protein siamchhuahte chu ER hmangin cell hmun hrang hrangah mamawh ang zelin thawn kual leh thin a ni.

13.Smooth Endoplasmic Reticulum SER

       SER hian cell tan thil pawimawh tak, fat molecules, a nih loh pawhin lipids siamchhuah nan a pui thin.

✅Endoplasmic Reticulum (ER) hna thawhte

Heng protein leh lipids thenkhat hian cell membrane siam nan an pui a. He process hi membrane biogenesis an ti.

✅Protein leh lipids dang thenkhat chu enzymes leh hormones angin an hna an thawk bawk.

ER hi cell hrang hrangah a lan dan a danglam hle chungin, network system angin a awm ziah thin.

Chuvangin, ER hna thawh pakhat chu cytoplasm hmun hrang hrang inkara thil (protein bik) phur kual nan channels anga hman theih a ni, a nih loh pawhin cytoplasm leh nucleus inkara phur kual nan.

✅ ER hian cell chhunga biochemical activities thenkhatna hmun atan cytoplasmic framework angin a hna a thawk bawk.

✅Vertebrates an tih, rannung hnungzang nei liver cell-ah chuan, SER hian tur leh damdawi hrang hrang detoxifying (tihrem)  nan hna pawimawh tak a thawk.

14.Golgi Apparatus a nih loh pawhin Golgi Complex

       Golgi apparatus hi membrane-bound vesicles an tih te, cisterns an tih, inthawh ang maia inphuah khawm, intlar parallel deuh hleka awmkhawm a ni.

✅ Heng membrane te hi ER membrane te nen inzawmna an nei tlangpui a, chuvangin complex cellular membrane system phek dang an siam.

✅ ER bula thil siamchhuahte chu golgi apparatus 

hmangin cell chhung leh pawn hmun hrang hrangah packaged (pack-in) leh dispatched (thawn chhuah) leh thin a ni.

✅A hna thawh zingah chuan thil siamchhuahte storage (dahkhawm), modification (tihdanglam) leh packaging (pack) te a tel a ni.

➡️ A thenkhatah chuan, complex sugar te hi golgi apparatus-ah simple sugar atangin siam theih a ni.

➡️ Golgi apparatus hi lysosome siamnaah pawh a tel bawk.

15. Lysosome-te

✅Lysosome-te hi cell bawlhhlawh paihna system ang deuh an ni.

✅Lysosome-te hian pawn atanga thil lut, bakteria emaw chaw emaw, leh cell organelle hlui tawhte an chhem tlem a, cell an tihfai theih nan an pui.

✅Pawn atanga thil lut, entirnan, bakteria emaw chaw emaw, leh organelle hlui tawhte chu lysosome-ah an lut a, chutah chuan an tichhe ta thin a ni. Lysosome-te hian hei hi an ti thei a ni, chhan chu organic thil zawng zawng tichhe thei digestive enzyme chak tak an pai vang a ni.

✅Cell metabolism a buai changin, entirnan, cell a chhiat hian, lysosome-te hi an puak thei a, an enzyme-te hian an cell ngei an tichhe thei a ni. Chuvangin, lysosome-te hi cell-in 'intihhlumna bag'(suitside bag) an tih bawk an ni.

✅lysosome-te hi membrane-bound sac, digestive enzyme-in a khat an ni. Heng enzyme-te hi RER-in a siam a ni.

16. Mitochondria

✅Mitochondria-te hi cell-in 'powerhouse' an tih an ni.

✅Nunna atana chemical activity hrang hrang mamawh energy chu mitochondria-in ATP (Adenosine Triphosphate) molecule hmangin a pe chhuak.[Mitochondria hi Power Plant a nih chuan. ATP hi Electricity a ni].

✅ATP hi cell-in 'energy currency' an tih a ni.

Taksa hian ATP-a energy inkhawl chu chemical compound thar siamnan leh mechanical work atan a hmang.

✅ Mitochondria-te hian membrane covering pakhat aia hnih an nei.

✅Mitochondria-te hi organelle mak tak an ni, anmahni DNA leh ribosome an nei tlat a ni. Chuvangin, mitochondria-te hian anmahni protein thenkhat chu an siam thei a ni [ribosome-te hian protein an siam].

17.Plastids

✅Tradescantia hnah cell-a cytoplasm-a rawng hrang hrang nei taksa te tak te awm i hmuh maithei. Hnah cell-a cytoplasm-ah an darh nuai a. Chung chu plastids an ti.

➡️ Rawng hrang hrang an nei a. Thenkhatin chlorophyll an tih, rawng hring an pai a. Rawng hring nei plastids chu chloroplasts an ti a. Hnah ah rawng hring an pe a ni.

➡️Chloroplasts hi photosynthesis atana pawimawh tak an ni.

➡️ Chloroplasts hian chlorophyll bakah rawng eng emaw orange pigments hrang hrang an pai bawk.

➡️ Plastids hi plant cell-ah chauh an awm a. Plastids chi hnih an awm—chromoplasts (rawng nei plastids) leh leucoplasts (rawng hlang emaw rawng nei lo plastids).

➡️ Leucoplasts hi starch, oil leh protein granules ang chi thil dahkhawlna organelle bulpui ber an ni.

Plastids chhunga inrelbawl dan chu stroma an tih thila membrane layer tam tak inphumkhawm a ni.

➡️ Plastids hi pawn lam inang deuhva mitochondria nen an inang a. Mitochondria ang bawkin, plastids pawhin anmahni DNA 🧬 leh ribosomes an nei bawk.

⬇️Summary

➡️Cell tin hian an structure leh function theihna chu an membrane leh organelles inrelbawl dan bik avangin an nei a. Chuvangin, cell hian structural organization bulpui a nei a ni. Hei hian cell-te chu respiration, nutrition lak, waste material tihfai, emaw protein thar siam ang chi function an perform theih nan a pui a. Chuvangin, cell hi living organism-te structural unit bulpui ber a ni. Nunna functional unit bulpui ber pawh a ni bawk.

➡️Cell-te hi lipids leh proteins atanga siam plasma membrane-in a hual vel a.

➡️Cell wall awmna hian plants, fungi leh bacteria cell-te chu hypotonic media-ah puak lovin an awm theih nan a pui a.

➡️ER function chu intracellular transport atana kawng bika hman theih leh manufacturing surface atana hman theih ve ve a ni.

➡️Golgi apparatus hi cell chhunga siam thil dahkhawl, tihdanglam leh pack-na function nei membrane-bound vesicles inphahkhawm a ni.

                              Thank you.                                    

✅Check your Performance here

📝UPSC/ MPSC and Other Competitive exam Questions bank:

1. Which of the following is/are correct about Probiotics?

1)Probiotics are made of both bacteria and yeast.

2)The organisms in probiotics are found in foods we ingest but they do not naturally occur in our gut.

3) Probiotics help in the digestion of milk sugars.

Select the correct answer using the code given below:

A. 1 only

B. 2 only

C. 1 and 3 only

D. 2 and 3

Answer: C (1 and 3) (UPSC 2022) 

2. Which of the following statements regarding the mitochondria and chloroplasts is incorrect?

A. Both are present in plant cells.

B. Both possess their own DNA and ribosomes.

C. Both are membrane-bound organelles.

D. Both are found in animal cells.

Answer: D (Chloroplasts are only in plant cells/algae) 

3. With reference to the cell structure, which of the following is considered the 'suicidal bag' of the cell?

A. Mitochondria

B. Lysosomes

C. Nucleus

D. Ribosomes

Answer: B (Lysosomes) (They contain digestive enzymes to break down waste) 

4. Consider the following statements about Prokaryotic cells:

1.They lack a defined nucleus.

2.Membrane-bound organelles are present.

3.They contain 70S ribosomes.

Which of the statements given above is/are correct?

A. 1 and 2 only

B. 2 and 3 only

C. 1 and 3 only

D. 1, 2 and 3

Answer: C (1 and 3) (Prokaryotes lack membrane-bound organelles) 

5. Which cell organelle is responsible for the packaging and modification of proteins?

A. Ribosome

B. Endoplasmic reticulum

C. Golgi apparatus

D. Lysosome

Answer: C (Golgi apparatus) 

6. Which of the following is responsible for the rigidity of plant cells?

A. Cell membrane

B. Cell wall

C. Cytoplasm

D. Vacuole

Answer: B (Cell wall) 

✅Exercises: 

1. Who first observed and described live cells using a microscope?

A. Robert Hooke

B. Anton van Leeuwenhoek

C. Robert Brown

D. Theodor Schwann

2. Which cell organelle is known as the "powerhouse of the cell" because it generates ATP?

A. Golgi apparatus

B. Lysosomes

C. Ribosomes

D. Mitochondria

 

3. The fluid mosaic model of the plasma membrane was proposed by:

A. Robert Hooke

B. Singer and Nicolson

C. Schleiden and Schwann

D. Rudolf Virchow

4. Consider the following statements regarding prokaryotic cells:

They lack a true nucleus.

They possess membrane-bound organelles.

They have 70S ribosomes.

Which of the statements given above is/are correct?

A. 1 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2 and 3

5. Plant cell walls are primarily composed of which substance?

A. Protein

B. Cellulose

C. Lipid

D. Starch

 

6. Which organelle contains digestive enzymes and enables intracellular digestion?

A. Golgi apparatus

B. Lysosomes

C. Vacuole

D. Nucleus

7. Which of the following is not considered a part of the endomembrane system?

A. Lysosome

B. Vacuole

C. Golgi complex

D. Peroxisome

 

8. Middle lamella is mainly composed of:

A. Hemicellulose

B. Muramic acid

C. Calcium pectate

D. Phosphoglycerides

📝Answer key:

1.B (Anton van Leeuwenhoek) 

2.Answer: D (Mitochondria)

3.Answer: B (Singer and Nicolson) 

4.Answer: B (1 and 3) 

5.Answer: B (Cellulose)

6.Answer: B (Lysosomes)

7.Answer: D (Peroxisome)

8.Answer: C (Calcium pectate)