Unit 1 : Characteristics of living

things
1. Classification
Biology is the learning of living things

A thing is living or not is defined by whether they can peruse :

- Movement, sensitivity, growth, respiration, excretion, reproduction,
nutrition
i. Movement: it could change its position
ii. Sensitivity: ability to detect and sense stimuli, response to environment
iii. Growth: increase in mass, to grow
iv. Respiration: produce energy by itself
v. Excretion: to depose - depose gas, liquid or solid
vi. Nutrition: taking in things for energy
vii. Reproduction: make more of a kind of organism

Cell is a living thing and is the smallest unit of the living

2. Animal classification
Ways of classification:
a. Morphology: decides by the overall shape of bodies
b. Anatomy: decides by internal organs
c. DNA: decides by four bases (AGCT) , genetic material ; compare the
sequences of bases

Classification tells us the revolutionary relationships between organisms

Species – means a group of organisms that can reproduce and produce fertile
offspring
 Fertile offspring: offsprings that could produce offsprings of themselves
Ie. Mule is a hybrid of horse and donkey, they could not give out offspring,
they are a living organism but not an species
 Hybrid : 杂种
Category : big —> small
Domain （域）> kingdom （界）> phylum （门）> class （纲）> order（目）> family（科）>
genus（属） > species （种）

Binomial naming 双名法 : genus + species

Eg. Canis Lupus

Dichotomous key 二分法 –

Ie. Statement ----- Yes or no
If no go to statement 2 If yes XXX (name of species)
3. 5 kingdoms
i. Animals
 Multicell
 Have nucleus, no cell wall & chloroplast
 Feed on organic substances
ii. Plants
 Multicell
 Have nucleus, cell wall (made of cellulose 纤维素)
 Go through photosynthesis ( chloroplast )
iii. Fungi
 Mostly multicell
 Have nucleus, cell wall (not made of cellulose)
 No chloroplast
 Consume by parasitic nutrition (寄生)
iv. Protoctista
 Multi or unicell
 Have nucleus
 May or may not have cell wall and chloroplast
v. Prokaryotes
 Unicell
 No nucleus, have cell wall ( not made of cellulose), no mitochondria
 Have DNA and flagellum (sometimes)
4. Phylum and class
Anima – kingdom l :
i. Vertebrate - phylum (AMBRF)
a. Fish - class
b. Amphibians
c. Reptiles
d. Mammals
e. Birds
ii. Annelids – worms
iii. Mollusks – snails
iv. Nematodes
v. Arthropods (MICA)
a. Crustaceans
b. Arachnids
c. Insects
d. Myriapods
5. Arthropods
Crustaceans
- More than 4 pairs of legs
- Breath by gills , aquatic
 Aquatic : live in water
- Hard shells + antenna
Arachnids
- Breath through book lung
- Terrestrial
 Terrestrial : live on land
- 4 pairs of leg , 2 body segments
- Pincers (claw like )

Myriapods
- Many body segments
- Each body segments have a pair of jointed legs
- One pair of antenna

Insect
- 1 pair of antenna
- 2 pair of wings
- 3 body segments : head, thorax, abdomen
- Breath by trachea
6. Plants
Flowering plants :
- Roots, stems, leaves, flowers
- Reproduce sexually by means of flowering and seeds

Ferns :
- Root, stems , leaves
- Leaves called fronds
- Reproduce by spores

Flowering plants :
i. Monocotyledon
 One leaf when germinates
 Have parallel veins on leaf
 3-9 petals on flower
 Fibrous roots
ii. Dicotyledon
 Two leaves when germinates
 Network of veins
 5 or 6 petals
 Tap roots

7. Virus
Virus is 20-200 nanometers long
Virus is not considered as a living organism
They could not reproduce without a host ; they use the host’s organ to
reproduce
No cellular structure + protein coat + generic material
Virus is parasites
 Parasites :寄生体

Micrometer : 1 * 10-6 m ( μm)

Real size in μm = size of image in μm/magnification

Unit 2 : Cell structure

1. Microscope
- Microscope
- Electron microscope
2. Animal cell
a. Cell membrane – controls what goes in and out, protect the cell and is
semi-permeable
b. Cytoplasm – fills up the cell, most of the cells activity happens here
c. Nucleus – contains DNA and controls the cell
d. Ribosomes – creates proteins
e. Mitochondria – help release energy by respiration, have chromosome and
DNA
f. Vacuole (not permanent in animal cell) – contains cell sap (solution of
sugar and other substances)
g. Nucleus envelope
3. Plant cell
a. Have all above
b. Cell wall – protects the cell, supports the cell, made of cellulose
c. Chloroplast – contains chlorophyll and starch grains, go through
photosynthesis
d. Permeant vacuole
4. Bacteria cell
a. Have all of organelles of animal cell except for nucleus and nucleus
envelope
b. Cell wall
c. Capsule
d. Pili
e. Flagella
f. Nucleoid
> circular strand of DNA
> plasmid DNA – give instructions to make proteins
> bacterial chromosome
5. Specialized cell
- Red blood cell
- Root hair cell
- Ciliated cell
- Sperm and egg
- Neuron cell
- Palisademisophlly cell – for photosynthesis
6. Organs
 Cell
 Tissue – group of cell
 Organ – made by different tissues to perform a special function
 Organ system

Unit 3: Movement in and out the cell

1. Diffusion
The movement of particles from high concentration area to lower
concentration area
It could take place in a cell and may or may not need a membrane
Diffusion does not need energy but it happens due to the pressure of kinetic
energy
Acetic acid – vinegar
Exp. Alveoli 肺泡 ileum 回肠
Factors affecting diffusion:
- Surface area
- Concentration gradient 浓度差
- Temperature
- Distance
2. Osmosis
How water diffuse in cell
It travels from high water potential to low water potential through a semi-
permeable membrane by net movement
Water potential – how many water particles / molecules in an area (against
concentration gradient)
Water particles aim to dilute a solution
3. Diffusion across a membrane
Visking tubing/ dialysis tube : a semi-permeable tube or wrapping
Sometimes the solution inside the tubing will not come out because of
molecules size
Diffusion and osmosis could happen at the same time
Pure water and concentrated solutions :
- When animal cel is put in pure water, it will burst due to osmosis
- When plant cell is out in pure water it will not burst but enlarge due to cell
wall and osmosis
 Turgid pressure – is created where the plant cell’s membrane presses to
the cell wall when large amounts of water is entering the cell
- When the animal cell is put into a concentrated solution it will shrink due
 to osmosis
- When a plant cell is put in concentrated solution it will become floppy
4. Active transport
Molecules transported against the concentration gradient using energy from
respiration
It needs transport proteins
a. Molecule bind to transport proteins on the cell membrane
b. Protein changes shape using energy from reparation
c. Molecule is pushed inside/outside the cell
Unit4：Macromolecules
1. Definition
All living things are made up by carbohydrates, lipids, proteins, DNA which are
found in cells
2. Carbohydrates
Carbohydrates attach to the surface of the cell (cell membrane) and acts as a
security guard of the cell (sensing activity)
- Monosaccharide 单糖
Simple sugar (glucose)
Glucose is C6H12O6 soluble in water
- Disaccharide 二糖
Made of glucose
- Sucrose 蔗糖
Maltose 麦芽糖 – malt sugar from plants
- Polysaccharide
a. Starch
b. Cellulose 纤维素
c. Glycogen 糖原 – in animal’s liver and muscles
Glucose is taken in epithelial cells 上皮细胞 on the villi by active transport
Starch tested by iodine, blue black if present
Glucose tested by benedict solution, red orange is present after heating
3. Lipids
3 fatty acid + 1 glycerol (how lipids are stored)
Provide energy and store energy, provide insulation
Tested by ethanol (achoo) – milky white (emulation) if present
Immiscible 不溶于水
4. Proteins
C，H，O，N + small amount of water
Amino acid => peptide => protein
Makes new cell, enzyme, antibody
Biuret test 双缩腺检测 （biuret reagent）- purple if present
5. DNA
Deoxyribonucleic
Have a double helix structure – spiral
DNA make up bases, between the structure is ladders
Ladders is made up by GCAT
G-guanine C-cytosine A-adenine T-thymine
Base pairing is what GCAT is on the other side (C-G A-T) – complementary
pairs
DNA coils make up chromosome
DNA aims to make proteins
Red blood cell is made from bones, it does not have a nucleus (no DNA) so it
could not replicate
It has hemoglobin that help catch oxygen and help deliver, C-G T-A C-G is the
chain to make hemoglobin. If the chain changes the red blood cell will become
sicked. 、