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Chapter 1

Objective Questions1D2C3A4B5D6A7C8B9C108

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1D2B3B4A5D6B7B8B

Objective Questions

Structured Questions(a) (i) A- Vacuole

B - Plasma membraneC - ChloroplastD - Cell u'allE - MitochondrionF - Crtoplasm

(ii) C - carry, out the photosynthetic processE - generate energ)- in the cell

(b)

nucleus

cyloplasm

cell rnembrane

(c) The plant cell comprises the cellanimai cells.

r,vall, chloroplast and a trig vacuole that is not found in

- has cellulose fibre and gives shape to the plant cell- surrounded b_v tonoplast and contains cell sap- contains chlorophl'Il pigments and carries out the photosyntheiic

process- controls the substances that enter and move out of the cell- control centre of all cell activities- substances in the cell that are located between the plasma

membrane and the nucleusNtitochondiion- the main site of energy generation, resulting from the oxidation of

lood

9Dl0B11 At2B13814A158

Essay Question1 (a) Cell wall

VacuoleChioropiast

MembraneNucleusCytoplasm

(b) r Put i.wo drops of distiiled water on the glass slide by using a dropper.o Use a small blade to cut a slice of red onion peel.o Use a forceps to remove the epidermis in the onion peel.o Place the epidermis in the drop of distilled water on the glass slide that is

prepared.

o

o

With the help of the perch needle, cover the epidermis with the glass slide cover.By using a light microscopg study the structure of the epidermis cell, first at a lowpower, and then at a high power.Transfer the glass slide from the microscope and place a piece of filter paper onone end ofthe glass slide cover.Drop iodine solution on the side of the glass slide cover while absorbing thesolution at the other end of the slide using filter paper.observe the glass slide again through the microscope at a low power in order tofocus at the cell. before changing to a higher power.Draw and label the onion cell structure that you observed through the microscope.

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Objective Questicns1C2Dln4C5B6B7B8D9C108

Structured Question(a) (i) 0 4 9/100 cm3

(ii) The solution is isotonic. The rate of water moving in and out of the cell is the same.As such, the red blood cell does not burst.

(iii) I Sweating2Urinating a lot and unne is dilute

(b) The salt solutiolr is hypotonic towards the liquid in the red blood cell. As such, the ivaterenters the red blood cell by osmosis and causes the volume of the cl.toplasm to increase.The plasma membrane is stretched beyond its elastic limit causing the red blood cell toburs1.

(c) This is because the onion cell has a hard cell wall and can prevent excess water fromentering.

(d) Excess fertilisers causes the soil solution to become a hypertonic solution compared withthe hair root cell sap. The water moves out from the root hair cell by osmosis causing theplant cell to suffer from a lack of water until the enzyme in the cell can no longerlunction.

Essay'Question(a) (D The intake of mineral salts occurs through active transportation, lvhich requires energy

from cell respiration. A condition with a lack of o"yg"n or the presence of respirationpoison stops/slows down the rate of cell respirahon to produce biological energy'.When the plant is transferred to a new location, part of its main root s"ystem is cutof?injured. As such, the rate of water absorption from the soil by the small plantdecreases. Cutting parts of the leaf helps io reduce the loss of water thrbughtranspiration.

(b)

palisademesoptryll

spongymesoph)rll

I

cuticle

upper epidermis

chloroplasts

\racuole

cytoplasm

nucleus

rylem tissue '\.tvern I nscular{ bundle

floem tissue J

lower epidermisguard cell