K.C.S.E Biology Q & A - MODEL 2019PP1QN03
The diagram below illustrates a specialised cell obtained from a certain tissue.
​(a) Name the cell.
(b) State two ways in which the cell is structurally adapted to its function.
answers
(a) nerve cell/motor neuron; acc neuron
(b) longer axon to transmit impulses/delivers action potential along way; has numerous dendrites for receiving/delivering /transmitting impulse; myelin sheath for faster transmission of impulse/insulation of axon; Schwan cell for secretion of myelin sheath; node of ranvier to enhance speed of transmission of impulse; cell body has nucleus for controlling nerve impulse transmission. K.C.S.E Biology Q & A - MODEL 2018PP1QN06
The diagram below illustrates tissue fluid and cells surrounding a capillary.
​(i)Name fluid G.
(ii) Give two ways by which fluid G is different from tissue fluid.
answers
(i) (Blood) plasma;
(ii) Has (more large) proteins/blood platelets; High (hydrostatic) pressure/low pressure of tissue fluid; Has red blood cells; K.C.S.E Biology Q & A - MODEL 2018PP1QN01
​(a) Name the cell organelle found in abundance in the white blood cells.
(b) Give a reason for your answer in (a) above. 
answers
a)Lysosomes/golgi apparatus;
b)White blood cells fight pathogens to protect the body, the lysosomes contain lytic enzymes which destroy pathogens;/golgi apparatus synthesize lysosomes which contain lytic enzymes that destroy parthogens; K.C.S.E Biology Q & A - MODEL 2017PP2QN03
The diagram below illustrates the appearance of a plant cell after it had been put in a certain solution.
​(a) Explain the appearance of the cell at the end of the treatment.
(b) Explain the results obtained if a red blood cell is subjected to the same treatment. (c) Explain why transfusion with distilled water is not recommended for a dehydrated patient.
answers
​(a) The cell is turgid; its cell sap was hypertonic (compared to the solution in which it was placed); by osmosis, water moved into the cell across its cell semi-permeable membrane, (swelling and becoming turgid);
(b)The red blood cell lacks the cell wall; water molecules move across its semi-permeable membrane by osmosis; into its hypertonic medium (inside the cell),cell contents/cytoplasm swelling and bursting haemolyses; (c)Would haemolyse; due, to lowering of the osmotic pressure of the blood below normal; K.C.S.E Biology Q & A - MODEL 2017PP2QN01
The diagram below represents a nucleus.
​(a) Name the structures labelled E and F.
(i) E F (ii) State the function of F. (iii) With reference to the nucleus, state one difference between an animal and a bacterial cell. (b) Name the plant cell organelle: (i) that stores chlorophyll (ii) responsible for intracellular digestion. (c) State two main functions of the vacuole in the amoeba.
ANSWERS
​(a) E—Nucleolus;
F — Nuclear pore/nucleopore; ii. Facilitates movement of materials in and out of the nucleus; iii. Nuclear material in the bacterial cell is not enclosed within a membrane /prokaryotic, while in animal cell it is enclosed eukaryotic; (b) i. Chloroplast; ii. Lysosome; (c) i. Feeding (food vacuole); ii. Osmoregulation (contractile vacuole); iii. Excretion/removal of wastes; K.C.S.E Biology Q & A - MODEL 2017PP1QN02
Below are diagrams of a cell organelle obtained from different organs of an animal
​(a) (i) For each organelle state an organ in the urinary system where it is likely to be found.
F G (ii) Give a reason for your answers in (a) (i) on page 2. (b) Name the part of the chloroplast where the following reactions occur: (i) Carbon(IV) oxide fixation (ii) Photolysis
answers
(a) (i) F - Kidney;
G - Bladder/Ureter/Urethra; ii) Kidney - active re-absorption of solutes requires more energy; organelle F has more cristae for attachment of more respiratory enzymes producing more energy; Bladder/ureter/urethra does not require as much energy/organelle G has less number of cristae hence fewer respiratory enzymes attached/less energy produced; (b) i) Stroma; ii) Grana/granurn;
K.C.S.E Biology Q & A - MODEL 2016PP1QN08
State three functions of Golgi apparatus.
answers
K.C.S.E Biology Q & A - MODEL 2014PP1QN20
State one function of each of the following cell organelles:
(a) golgi bodies (b) lysosomes.
ANSWERS
​(a) Packaging of substances/glycoproteins/ transportation of glycoproteins;
Secretion of synthesized proteins and carbohydrates; Formation of lysosomes/modification of carbohydrates to form glycoproteins; (1 mark) (b) Digestion of food/Breakdown large molecules; Destroy worn out organdies or cells/tissue; K.C.S.E Biology Q & A - MODEL 2013PP1QN09
State one way in which each of the following is structurally adapted to its function:
(a) neurone; (b) mitochondrion.
answers
a)Presence of myelin sheath for insulationlincreases transmission; Axon for transmission of impulses;
Large cell body controls activites of cell; Nerve endings/dendrites receives impulses from receptors cells; Node of Ranvier speeds up impulse transmission. (b) Inner membrane highly folded/cristae to increase S A for attachment of (respiratory) enzymes. K.C.S.E Biology Q & A - MODEL 2013PP1QN02
The diagram below represents a cell as seen under an electron microscope.
​(a) Based on the diagram, state whether it represents an animal cell or a plant cell.
(b) Give two reasons for your answer in 2(a) above. (c) Why is the palisade layer a tissue?
answers
​(a) Animal cell;
(b) Has cell membrane only/has no cell wall; Has numerous small vacuoles; Has central nucleus; (c) Consists of many similar cells performing the same function; K.C.S.E Biology Q & A - MODEL 2012PP1QN30
Name the organelle that is involved in each of the following:
(a) manufacture of lipids (b) formation of lysosomes
answers
K.C.S.E Biology Q & A - MODEL 2012PP1QN27
What is the function of contractile vacuoles in amoeba?
answers
K.C.S.E Biology Q & A - MODEL 2012PP1QN03
The figure below is a fine structure of a generalised animal cell as seen under an electron microscope.
​(a) Name the parts labelled A and B.
A B (b) How is the structure labelled B adapted to its function?
answers
​(a) (i) A - nucleopore;
B - Rough Endoplastic Reticulum; (b) Surface covered with ribosomes; for protein synthesis; Has interconnected channels: for transportation of proteins;
K.C.S.E Biology Q & A - MODEL 2010PP1QN09
State two ways in which chloroplasts are adapted to their function.
answers
K.C.S.E Biology Q & A - MODEL 2010PP1QN03
State the functions of:
(a) Ribosomes; (b) Lysosomes.
answers
(a) Protein synthesis
(b) Destroys worn out organdies and micro-organism; |
TOPICSFORM 1
Form 2
Form 3
Form 4
ARCHIVES
CATEGORIES
Categories
All
RSS FEEDS
|
RSS Feed