Biology Spm

Biology (Revisio Biology n)

SPM

4551/2

Tissue Orga n

Differentiation

Contraction and relaxation for peristalsis.

Digestive system

To break down complex food substances into simpler / soluble molecules small enough for absorption.

Diabetes mellitus P1:(Islet) cells in pancreas cannot secrete insulin P2:Glucose cannot be converted to glycogen P3:Increase in blood glucose level

Frequent urination Blurred vision Dizziness Always feel thirsty

Tertiary Secondar y Quartenar

Hydrolysi s

X X Z

The temperature in refrigerator is low. Enzyme(in bacteria) is inactive. Food is decomposed slowly.

Control the temperature at 40 0C. 40 0C is an optimum temperature for enzyme activities. Enzymes catalyse the reaction at maximum rate.

G1: Growth phase S: Synthesis phase

R : Cell grows by synthesising proteins and new cytoplasmic organelles/chromosomes become chromatin. S : Synthesis of DNA. U : Cell division takes place // Mitosis occurs followed by

P1: The chromosomes are pulled towards the opposite poles.(shortening of the spindle fibres) P2: Each pole receives only one of each homologous pair of

24 chromosomes

P1: Caused by severe disruption to the mechanism that control cell cycle. P2: Cancerous cells divide uncontrollably P3: Cancer cells compete with surrounding normal cells to obtain

* via the cytoplasm via the vacuole via the cell wall

P1 : Cytoplasm of root hair cells are hypertonic compared to surrounding soil water. P2 : Water enters the root hair cells via osmosis. P3 : The root hair cells become hypotonic compared to adjacent hypertonic cells. P4 : Water diffuse into adjacent cells via osmosis (cortex to endodermis to xylem vessel)

P1 : The narrow diameter of xylem vessels increase the forces generated by capillary action. P2 : Water molecules adhere to one another by cohesive force (hydrogen bond) P3 : Water adhere to walls of xylem vessels

P1 : Light stimulates photosynthesis in the guard cells P2 : The guard cells start producing glucose. P3 : Potassium ions are accumulated from adjacent cells through active transport. P4 : Guard cells become hypertonic and water moves in by osmosis. P5 : Guard cells swell up / become