Bio my one

What is Life

A state of chemical balance (homeostasis) that reproduces and evolves over generations

Charecteristics of life

SNR GERMS → Specific organisation, nutrition, reproduction, growth, excretion, respriation, movement, sensitive to surroundings

Recall structural levels of organisation

Molecules, cells, tissues, organs, organ systems, organisim

Epithelial tissue

• tightly packed cells

• covers surfaces and lines internal surfaces.

• Protection, secretion and absorbtion

example of epithelial tissue

Epidermis of skin

Lining of blood vessles

lining of intestines

types or epithelial tissue (layers)

simple, stratified, cuboidal, columnar, or squamous.

connective tissue

loosely packed cells

obvious matrix

examples of connective tissue

cartlidge, bone, blood, fat

muscular tissue

elongated and can contract

types of muscle tissue

skeletal, cardiac, smooth

skeletal muscle tissue

attatched to bone

striated

stripey

volentary movement

cardiac muscle tissue

in heart

is striated

stripey

involuntary

smooth muscle tissue

in walls of hollow organs

not striated

involuntary

nervous tissue

very irregular shape

sense stimuli

transmit signals

support glial cells

define tissue

a group of specialised cells (and cell products) that work together for a particular function

cell theory

all organisims are made up of 1 or more cells

all cells come from pre-existing cells

cells are the smallest organisational (structural and functional) unit of life

2 major cell types

prokaryotic and eukaryotic

Eukaryotic and prokaryotic similar features (4)

cell membrane, cytoplasm, ribosomes, DNA

role of cytoplasm

jelly like material which organelles float in

chemical reactions occur here

role of nucleus

contains genetic material

cell’s control center

role of nucleolus

production and assembly of rRNA

role of ribosomes

site of protein production

role of cell membrane

selectively permiable barrier which controls what enters and leaves the cell

role of cell wall

provides support strength and protection to plant cells

role of rough endoplasmic reticulum (rough ER)

transport of proteins and lipids

role of smooth endoplasmic reticulum (ER)

transport of proteins and lipids

difference between Rough ER and Smooth ER

Rough ER has ribosomes attatched and smooth ER does not

role of Golgi Apparatus (golgi body)

protein packaging after recieved from ER

role of lysosomes

waste removal

role of centrioles

direct chromosome movement during cell division

role of vacuoles

storage of water and nutrients

difference between vacuoles in plant and animal cells

plant cells have 1 large vacuole, animal cells have many small vacuoles

role of mitocondria

site of cellular respiration and energy production

role of chloroplasts

site of photosynthesis in plant cells

types of microscopes (3)

light, compound, electron

electron microscope

large magnification

very good resolution

specimen must be dead

advantage of compound light microscope

affordable

disadvantage of compound light microscope

max resolution of 2um

advantage of electron microscope

x2,000,000 magnification

disadvantage of electron microscope

expensive

features of good biological drawing

• Draw what is seen (to a large size eg. A5)

• Use a sharp pencil

• Position drawing in the centre of page

• Clear lines not sketchy and shapes complete.

• Don’t shade, (stippling may be used)

• Labels – on right, with horizontal lines, not crossing

• Include title, magnification of drawing, names of structures

Diameter field of view formula

field number (18)/objective magnification

what is 1mm equial to in um

1,000 micrometers

real life size formula

diameter field of view/number of cells that fit across field of view

magnification of drawing formula

size of drawing (um)/real life size (um)

which photosynthetic pigment is the most important

chlorophyll A

why is chlorophyll A green

reflects alot of green light and absorbs mainly blue and red wavelengths.

which colour has longest wavelenglth

red

which colour has the shortest wavelegth

violet

factors affecting rate of photosynthesis (4)

light intensity levels

co2 levels

temperature

water availability

define phototaxis

movement of an organism toward or away from a light source

exampls of a phototaxic organisim

euglena

photosynthesis word equation

carbon dioxide + water → glucose + oxygen

photosynthesis chemical equation

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

where does photosynthesis take place

chloroplasts

name the 2 stages of photosynthesis

light dependant reaction, light independent reaction

where does the light dependent reaction take place

grana (thylakoid discs) inside chloroplasts

what happens in light dependent reaction

chlorophylls absorb solar energy and split water into hydrogen (NADPH2/NADP) and oxygen, as well as producing some ATP molecules

where does the light independent reaction occur

stroma inside chloroplasts

what happens in light independent reaction

ATP is used to combine carbon and oxygen with hydrogen to produce triose phosphate

what is the light independent reaction otherwise known as

calvin cycle

enzyme important to the light independant reaction

RUBISCO

what are triose phosphate molecules combined to form?

glucose

what is glucose combined to form

starch (for storage)

what is a disease

abnormal condition of an organisim which interrupts normal bodily functions

define a sign

somthing that can be measured by another individual

example of a sign

a temperature

rash

define a symptom

somthing that can be experioenced only by the individual

example of a symptom

pain

nausea

fatigue

major differencating factor between non infectious and infectious disease

non infectious disease are not caused by pathogens

virulence

the ability for a pathogen to cause disease

6 major groups of pathogens

prions

viruses

bacteria

fungi

protozoa

multicellular parasites

example of prion

mad cow disease

what does a prion do?

misfold proteins that damage the brain

example of a virus

influenza

example of bacteria

strep throat

example of fungi

athletes foot

example of protozoa

maleria

example of multicellular parasite

tapeworm

how can disease be spread (5)

direct contact

contact with body fluids

contaminated food

water

vector organisims

what does a vaccination involve

weakened or killed pathogen (or antigens) to stimulate an immune response

what can antibiotics be used for

bacterial infection

what can antifungal medication be used for

fungal infection

what can antiviral medication be used for

viral infection

what is in the first line of defence

physical and chemical barriers

examples of first line of defence

skin

enzymes

mucous secretion

goal of first line of defence

prevent disease entry to body

what does the second line of defence involve

phagocytic white blood cells (neutrophils and macrophages)

physical traits from second line of defence

infammation at site of infection

what do macrophages do

‘eat’ foreign cells/pathogens

what does the third line of defence involve

immune system specific white blood cells (lymphocytes)

major divisions of the third line of defence

cellular and homoral immunity

what type of blood cells are used in cellular immunity

T Lymphocytes

what do t lymphocytes do

enlarge and divide to kill pathogen

where do t lymphocytes mature

thymus gland

what type of blood cells are used in humoral immunity

B Lymphocytes

where do b lymphocytes mature

bone marrow

what do b lymphocytes replicate to become

plasma cells

where are antibodies and antigens used

3rd line of defence

define antigen

a molecule found on surface of pathogens which promote a specific immune responce