nota biology

8/2/2019 Nota Biology

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Is your impression ofbiology limited to the dissection of frogs? It seemed like every Hollywood

movie depicts biology lessons as one which involves dissection of frogs and mice. Well, it is not

entirely wrong, but it does not show the whole picture. Biology encompasses more than that and it

focuses on the natural science with regards to the study of life and living organism. So, for new SPM

biology students in Form 4, Berry Berry Easy would like to share with you some teasers on the

subject of biology.

SPM Biology Form 4 Notes Terminology and Concepts: Introduction to Biology

Light Microscope

Biology and Its Importance

Biology - earlier study as Botany (study of plant) and Zoology (study of animals) but now ModernBiology has many fields such as Genetic Engineering, Biotechnology and Bacteriology.

Biology - the scientific study of life.

Its Importance:

1. Education.

2. Knowledge

3. Control

4. Research

5. Economy

6. Quality of life

7. Diseases

8. Problem solving

9. Careers

Scientific Investigation

The following are steps involved in a scientific investigation:

1. Define the problem

2. Form a hypothesis

3. Plan the investigation

4. Control the variables

5. Collect the data6. Analyse the data

7. Interpret the data
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8. Make a conclusion

9. Write a report

Berry Berry Teacher would like to recommend young berries to follow these rules in writing their

report:

1. Aim / Objective

2. Statement of problem (must be in the form of question)3. Hypothesis

4. Variables (Manipulated, Responding and Fixed)

5. Materials

6. Apparatus

7. Technique

8. Procedure / Method of the experiment

9. Results / Record of data

10.Discussion / Presentation of data

11.Conclusion (accept of not accept the hypothesis)

So there you go, a teaser on biology. Now, does that make you wanting for more? Biology is really a

genuinely fun and interesting subject, once you appreciate the beauty of life. Check back for more

notes on the subsequent topics of SPM biology.

SPM Biology Form 4 Notes Terminology and

Concepts: Cell Structure and Cell Organisation

(Part I)by BerryBerryTeacher on 09/02/2010

in Berry Reference (Notes)

Still not put off by the introduction to biology? Well, then continue on to appreciate the beauty of life

starting with the basic structural and functional unit of all living organism, cells. This post by the

Berry Berry Teacher will be very useful for the understanding of cells, inclusive of structure and

organisation. This is also part 1 of the series involving cells. Be sure to compare and contrast the

animal and plant cells if you want to understand cells.

SPM Form 4 Terminology and Concepts: Cell Structure and Cell Organisation
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Neuron cell

Cell Structure and Function

Comparison between Animal Cell (AC) and Plant Cell (PC)

1. Mitochondrion (pl: Mitochondria): AC and PC

spherical / rod-shaped organelles

two membranes : Inner membrane form cristae & Outer membrane regular and smooth

an energy source

site of cellular aerobic respiration

produces ATP (adenosine triphosphate)2. Nucleus (pl: Nuclei): AC and PC

contains the genetic material

regulates and controls the activities of the cell

an organelle bounded by double (2) layers of nuclear membrane with pores and selectively

permeable

responsible for all cellular structure, chemical functions, growth and reproduction

separates the genetic materials (chromatin) from cytoplasm

3. Nucleolus: AC and PC

spherical structure within the nucleus consists of DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) and proteins

visible when the cell is not dividing

synthesis RNA which is needed to make ribosomes

4. Nucleoplasm: AC and PC

fluid contained within the nucleus

highly viscous solid

made up of the chromatin and the nucleolus

5. Chromosomes

thread-like structures (consists of genetic material)

appears as chromatin spread throughout the nucleus in the form of tiny granules
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chromatin condenses into chromosomes (during cell division)

carry genetic information in its DNA

6. Ribosomes: Ac and PC

small dot-like organelles

protein synthesis

consist of RNA (ribonucleic acids) smallest cellular organelles

attached on the surface of ER and occur freely in cytoplasm

7. Endoplasmic reticulum (ER): AC and PC

connected to the nuclear membrane

synthesises proteins, steroids and lipids

collects , stores and distributes protein, steroids and lipids

exists as rough ER and smooth ER

Rough ER: covered with ribosomes, flat sealed sac which continued from the nuclear

membrane, transports protein, and have a large surface area for chemical reactions. Smooth ER: does not have ribosomes, transports lipids and presents in large amounts of cells.

8. Plasma membrane: AC and PC

cell membrane

thin membrane surround the cytoplasm of a cell

selectively permeable / semi permeable

a protective and selective outer barrier

consists of phospholipids and protein molecules

To be continued.. Upcoming post involves Golgi apparatus/body, Cytoplasm, Lysosome, Centriole,

Vacuole, Cell wall, Chloroplast.

Keys:

AC and PC = similarities

AC or PC = differences (Carbohydrates storage: AC = Glycogen / PC = Starch)



(Part II)by BerryBerryTeacher on 12/02/2010


Continuing from Part 1 of Cell Structure and Organisation, Berry Berry Easy will like to present you

with part 2 of the same topic. The previous part involved Mitochondrion, Nucleus, Neucleolus,

Neucleoplasm, Chromosomes, Ribosomes, Endoplasmic reticulum and Plasma membrane. So be sure

to check out the previous post.

SPM Form 4 Terminology and Concepts: Cell Structure and Cell Organisation


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Neuron cell

Cell Structure and Function

Comparison between Animal Cell (AC) and Plant Cell (PC)

9. Golgi apparatus / Golgi body: AC and PC

bound sacs

processes , packages and transport molecules synthesised in the cell

forms lysosomes

transports and stores lipids

synthesis of carbohydrate from hormone changes protein into glycoprotein

excretes waste products out of the cell

10. Cytoplasm: AC and PC

aqueous solution (except nucleus)

stores water, enzymes, nutrient, salts and dissolved gases

provided support, shape and protects the cell organelles

medium for metabolic reactions

provides substances

11. Lysosome: AC sac-like organelle with one membrane

digest proteins, lipids and carbohydrates

removes undigested materials

releases enzymes to digest external materials

12. Centriole: AC

are paired cylindrical organelles

nine tubes with three tubules each

produces spindle during cell division (mitosis and meiosis)

migrate to the opposite poles of the cell (during cell division will be discussed in Chapter 5Cell Division)

13. Vacuole: AC (temporary / lower class species) and PC


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small cavity in the cytoplasm

bound by a single membrane

filled with cell sap

storage of food (protein, oil and water)

some vacuoles remove metabolic waste

functions as cell expansion

Amoeba: food vacuoles (phagocytosis)

Paramecium: contractile vacuoles (expel water)

14. Cell Wall: PC

rigid and tough cellulose layer surrounding the plasma membrane (cell membrane)

protects and supports the cell

maintains the shape

prevents the cell from busting (excessive intake of water)

allows substances to move freely through the cell wall

15. Chloroplast: PC

disc / lens-shaped organelle

have two membranes: inner and outer membrane

contains chlorophyll in the grana to trap sunlight energy

carry out photosynthesis in the chlorophyll

storage of food and pigments

Keys:

AC and PC = similarities

AC or PC = differences (Carbohydrates storage: AC = Glycogen / PC = Starch)

The notes for this topic is not yet complete, so check out for Part III. Log on frequently to BerryBerry Easy for more notes.



(Part III)by BerryBerryTeacher on 04/03/2010


This is the penultimate post from Berry Berry Easy (3rd of 4) in the series of notes in Cell Structure

and Cell Organisation. Before you all forget what is from the previous two posts, let us do a recap on

part 2 which involvedorganelles, mitochondria for animals, chloroplast for plants and the uniqueness

of cells. Do check out also the first post that contained Mitochondrion, Nucleus, Neucleolus,

Neucleoplasm, Chromosomes, Ribosomes, Endoplasmic reticulum and Plasma membrane. So, do

distinguish the difference between animal and plant cells.

SPM Form 4 Terminology and Concepts: Cell Structure and Cell Organisation (Part III)


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Neuron cell

Organelles (little organ) tiny structures inside a cell that perform specific functions for a cell.

Example: mitochondria, lysosome and chloroplast.

Mitochondria

Animal: High density at sperm cells (at middle piece to provide sufficient energy for motive

power), flight muscle cells (bird / avian), liver cells, meristematic / meristemic cells (involve

with cell division), kidney cells, heart muscle cells, brain cells.

Chloroplasts

Plant: High density at palisade mesophyll (leaf: below upper epidermis). It functions to trapsunlight to synthesise sugar during photosynthesis.

The Uniqueness of The Cell

A cell is unique:

1. Specialisation

2. Division of labour

3. Coordination and integration

Example of specialisation of cells :

Animal smooth muscle cell, neuron (nerve cell), white blood cell, red blood cell

(erythrocyte), cheek cell (lining epithelial cell), sperm, ovum cell (the biggest cell in human)

Plant palisade mesophyll cell, xylem, phloem, guard cell.

Do check out the final post in the series forSPM Form 4 Biology notes on Cell Structure and Cell

Organisation.



(Part IV)by BerryBerryTeacher on 06/03/2010


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Finally, the 4th orconcluding post in the series for SPM Biology Form 4 notes on Cell Structure and

Cell Organisation.(Do check out the previous three post on the same topic, easiest to find by clicking

on related posts) To close this chapter, Berry Berry Easy would like to focus on cell organisation

and their differences in various organisms. Be sure to read all four posts as a whole to understand the

whole picture.

SPM Form 4 Terminology and Concepts: Cell Structure and Cell Organisation (Part IV)

Neuron cell

Cell Organisation

Unicellular A single cell performs all the basic life process. Example:Amoeba sp.,Paramecium sp.,

Chlamydomonas, Bacteria and Euglena.

Multicellular An organism consists of more than one cell. Each group of cell specialized to carry

our life processes. Example:Homo sapien (human), animals and plants. It has five levels of

organisation

1. Cells: basic units of structure and function.

Example: Red blood cells and xylem vessel cells.

2. Tissues: made up of cells with similar in structure and function.

Example: Epithelial tissues and vascular tissues.

3. Organs: made up of tissues that perform a specific function.

Example: Heart and flower.

4. System: two of more organs that perform a specific function.

Example: Digestive system and root system.

5. Organisms: whole living thing that carry out all the basic life processes.

Example: Human and durian tree.

Cell Organisation (Unicellular) inAmoeba sp. (lives in freshwater ponds) andParamecium sp.

(lives in soil and moist area)

1. Cell structure

Amoeba sp.: plasma membrane, food vacuole, contractile vacuole, pseudopodium, nucleus,

ectoplasma, endoplasm. Paramecium sp.: food vacuole, posterior contractile vacuole, cytostome, gullet, oral groove,

cilia, macronucleus, micronucleus, anterior contractile vacuole.
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2. Locomotion

Amoeba sp.: Pseudopodium (false foot) helps it to move forward slowly and it is known as

amoeboid movement.

Paramecium sp.: Hair-like cilia to beat against water. It beats its cilia backwards diagonally

(swim forward) and it rotates on its axis. It beats its cilia forward (swim backwards).

3. Feeding

Amoeba sp.: Omnivore. Eat bacteria, plant cells, algae and other microscopic organisms.

1. Entrapment extend pseudopodium.

2. Engulfment engulf tiny food (phagocytosis) with its pseudopodia.

3. Digestion food enclosed in food vacuole

4. Absorption enzyme digests the bacteria

5. Egesting expel indigestible material.

Paramecium sp.: Eat bacteria, organic material and other microscopic organisms.

1. Sweeping movement of cilia. Food moves along the oral groove into the gullet and

cytostome.2. Digestion food vacuole circulates round the cell.

3. Elimination undigested food is eliminated at the anal pore.

4. Reproduction

Amoeba sp.: two types of reproduction.

1. Binary Fission nucleus divides (favourable condition) and then follows by division of

cytoplasm. Two daughter cells are formed (mitotic division).

2. Spore Formation spores form (bad condition) and germinate into new amoeba under

favourable condition.

Paramecium sp.: two types of reproduction.

1. Binary Fission micronucleus undergoes mitosis (favourable condition). Macronucleus

begins to elongation and form two. Cell content divide and two daughter cells are formed.

2. Conjugation (Sexual reproduction) two same species parent paramecia exchange genetic

material of their micronuclei. Each parent divides and forms four daughter cells.

5. Osmoregulation

Amoeba sp.: water moves into the cell by osmosis and prevention of bursting, it has a

contractile vacuole.

Paramecium sp.: water moves into the cell by osmosis and prevention of bursting, it has two

contractile vacuoles.

6. Respiration

Amoeba sp. andParamecium sp. (both): exchange gases throughout the whole cell membrane

7. Excretion

Amoeba sp. andParamecium sp. (both): waste products are ammonia and carbon dioxide by

diffusion. Solid waste in paramecium is expelled through its anal pore.

Cell Organisation (Multicellular) in Human

1. Cells: Epithelial cells, muscle cells, white blood cells, red blood cells, sperm, nerve cells.

2. Tissues: Epithelial tissue, smooth muscle tissue, connective tissue, skeletal tissue, nervetissue.

3. Organs: Stomach, heart, kidney, lung, liver.


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4. Systems: Circulatory system, respiratory system, digestive system, excretory system,

muscular system, lymphatic system, integumentary system, skeletal system, nervous system,

endocrine system, reproductive system.

5. Organisms: Human.

Cell Organisation in Plant

1. Cells: Parenchyma cells, collenchyma cells, sclerenchyma cells, epidermal cells.2. Tissues: Epidermal tissue, meristem tissue, vascular tissue.

3. Organs: Leaf organ, flower organ, stem organ, root organ.

4. Systems: Shoot system, root system.

5. Organisms: Plant.

So do revise on all four posts in the series if you want to understand the gist of Cell Structure and Cell

Organisation. Especially useful forForm 4 students who are new to SPM Biology.

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Concepts: Movement of Substances Across the

Plasma Membrane (Part I)by BerryBerryTeacher on 15/06/2010


Berry Berry Easy is back with SPM Form 4 Biology notes for Movement of substances across

the plasma membrane. The plasma membrane is a membrane of biological nature which forms thebarrier between the interior of a cell against external environment. However, do not just think of it as

a layer which do not have any function. Typically, movement of substances to and from cells to outer

environment is controlled (due to its permeability) by the plasma membrane. The key concept here for

this topic is to understand the selective-permeability nature of a plasma membrane. The rest of the

topic are rather easy and intuitive. Do note that plasma membrane is also known as cell membrane

and plasmalemma.

SPM Biology Form 4 Terminology and Concepts: Movement of Substances Across the Plasma

Membrane (Part 1)


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Permeability of the fruit skin

1. Uniqueness of PlasmaMembrane (also known as cell membrane):

it is a semi-permeable cell membrane

it allows water and certain substances to move in and out of the cell.

2. Importance ofPlasma Membrane:

- cells obtain nutrients and gases

cells excrete metabolic wastes

cells can maintain pH for enzyme activity

cells can maintain ionic concentration of the cells for enzyme activity control the types and the amount of substances

allow useful substance (hormones/enzymes) to secrete from cells

protect cells

a boundary between the inside and outside of cell.

3. Structure of the basic unit of plasma membrane

Phospholipid molecule:

Head hydrophilic: a polar phosphate molecule (philic~loves water / attracted to water)

Tail hydrophobic: two non-polar fatty acids (phobic~hates water / repelled to water)

Formation:

Hydrophilic heads pointing outwardsHydrophobic tails pointing inwards

(Bilayer phospolipid)

Fluid Mosaic Model (Protein embedded in the bilayer)

Carrier protein

carrier for some molecules (glucose, amino acids, proteins and nucleic acids)

controls the movement of ions and particles (Na+, Ca2+ and K+)

Glycoprotein

Glycolipid combination of lipids and polysaccharides

4. Permeability
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Materials must be able to move through the plasma membrane in order for the cell cytoplasma to

interact with the external environment. Therefore, the movement of soluble substances can occur in

several mechanisms:

A. Process of Passive Transport

B. Process of Active Transport

A. Passive Transport

i) Simple Diffusion

not selective: lipid-soluble molecules, gases and water.

not control by cell.

movement of the molecules from a region of higher concentration to a region of lower

concentration.

Factors affecting the rate of diffusion are temperature, size of molecules/ions, diffusion

gradient, surface area and diffusion medium.

example: diffusion of oxygen and carbon dioxide at the alveolus.

ii) Osmosis:

only water molecules.

not control by cell.

movement of water from a region of higher concentration to one of lower concentration and

often occurs across a semipermeable membrane.

strong sucrose solution = less water molecule = low water potential.

weak sucrose solution = more water molecule = high water potential.

example: absorption of water by root hairs.

iii) Facilitated Diffusion:

very specific: glucose, nucleic aicds, amino acids, protein and mineral ions.

control by cell.

transport of molecules (only certain molecules) across the outer membrane of living cell by a

process of carrier protein (hydrophilic group) / channel protein (Ions: Na+, Ca2+, K+) withinthe cell membrane.

normally take place from a region with higher concentration of molecules to a region of lower
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concentration.

example: absorption of digested food in the villus.

B. Process of Active Transport

very specific: minerals ions and amino acids.

control by cell.

This process needs carrier proteins and energy (due to against concentration gradient) from aregion of lower concentration to a region of higher concentration).

Cell must expend energy that derived from ATP (adenosine triphosphate)

example: human nerve cells (sodium ions are constantly transport out of the cell) / ions intake

by root hairs of a plant.

Finally, the end of this part. Stay tune for the final part (Part 3) of SPM Biology Form 4 notes on

Movement of substances across the plasma membrane.


Concepts: Movement of Substances Across the

Plasma Membrane (Part III Final)by BerryBerryTeacher on 02/07/2010


Ever wondered why you need to drink isotonic drinks (100 Plus as an example) after doing sports?

Okay, mainly because it tastes good as any sweetish cold drink after much exercise is appreciated.

However, isotonic drinks does more than that as it replenish fluids after you lose some fluid through

sports. Well, Berry Berry Teacher thinks that most of our knowledgeable Berry Readers knowsabout the isotonic part, but how about hypotonic and hypertonic? Hypertonic do not make you any

more hyper, while hypotonic do not have anything to do with hippopotamus. So let us ride through

the journey of substances across plasma membrane with Part 3 (final part) of this series.

SPM Form 4 Terminology and Concepts: Movement of Substances Across the Plasma

Membrane (Part 3 Final)

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Type of Solution

1. Hypotonic

2. Isotonic

3. Hypertonic

1) Hypotonic

Solute concentration in the external solution is lesser than solute concentration inside the cell.

Water concentration outside the cell is higher than the water concentration inside the cell.

2) Isotonic

Solute concentration in the external solution is equal to the solute concentration inside the cell.

Water concentration inside and outside of the cell is the same.

3) Hypertonic

Solute concentration in the external solution is greater than solute concentration inside the

cell.

Water concentration outside the cell is lower than the water concentration inside the cell.Types of solutions:

Type of

Solution

Hypotonic Isotonic Hypertonic

Animal

Cell

The cell inflates due to

the water molecules enter

the cell. Eventually it

bursts (thin plama

membrane). Example: red

blood cell in distilled

water.

No change in the

size of cell. Net

movement of

water is

zero. Example:

red blood cell in

0.85% sucrosesolution.

The cell shrinks and

becomes soft and

dehydrated due to the

water molecule leave the

cell. Example: red blood

cell in 5% sodium

chloride solution.

Plant Cell The cell expands and

becomes firm / turgid due

to the water molecules

enter the cell. The rigid

cellulose cell wall

expands slightly and

prevents cell from

bursting. Example: strip

of potato in distilledwater.

No change in the

size of cell. Net

movement of

water is

zero. Example:

strip of potato in

5% sucrose

solution.

The cell becomes flaccid

(plasmolysis occurs),

vacuole and cytoplasma

shrink due to the water

molecules leave the

cell. Example: strip of

potato in 30% sucrose

solution.

Application

1. Food is soaked in a concentrated salt solution to prevent bacteria and fungus to survive.

2. Chemical fertiliser (dissolved ions) increases solute concentration (decrease water molecules)

in soil. Therefore, water leaves from the cell sap of the plant which result the plant wither.

Finally, the end of the interesting substance movement over plasma membrane. Do keep note that this

might be a popular essay question. Easy to answer but hard to score, so take note of the terminologies

and concepts shown above.

nota biology

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