Biology Need to Know: Gaps in Knowledge

Tidal volume

The volume of air in each breath

Volume in tidal volume

0\.4 dm³

Vital Capacity

The maximum volume of air that can be breathe in or out

Breathing rate

How many breaths are taken per unit time (usually minute)

Oxygen uptake

The rate at which a person uses up oxygen (usually dm³ per minute)

Light microscope maximum resolution

0\.2 um

Light microscope maximum magnification

X 1500

Light microscope image type

2D, colour

Advantage of light microscopes

Can see at different depths

Disadvantages of light microscopes

Not very high resolution or magnification

Scanning electron microscope maximum resolution

0\.002 um

Scanning Electron Microscope maximum magnification

X 500 000

S.E.M image type

3D

Advantage of S.E.M

Shows the surface of the specimen

Disadvantages of S.E.M

Lower resolution than T.E.M

Transmission electron microscope maximum resolution

0\.0002um

T.E.M maximum magnification

X 1 000 000

T.E.M image type

2D

T.E.M advantages

High resolutions so can look at organelle structures in detail

T.E.M disadvantages

Specimen needs to be very thinly sliced

Monocyte image

Monocyte role

Biggest white blood cell and a phagocyte

Identifiable features of monocytes

Kidney shaped nucleus and non-grainy cytoplasm.

Neutrophil image

Neutrophil identifiable features

Multi-lobed nucleus and grainy cytoplasm

Lymphocyte image

Lymphocyte identifiable features

Nucleus dominates most of the cell, non-grainy cytoplasm. Lymphocyte are much smaller than neutrophils

Cellulose structure image

Which monomer of glucose does cellulose use

β glucose

Which bonds does cellulose have

β glucose 1,4 glycosidic bonds

Properties of cellulose:

* insoluble in water
* High tensile strength, due to the alternate arrangement of glucose molecules
* Soluble in organic solvents

What organelle is cellulose most commonly found in?

Plant cell walls

Starch structure image

What two monomers make up the starch polymer

Amylose and amylopectin

What is starch found as in plant cells

Granules

What is the purpose of starch

As a glucose storage molecule for plants

Amylopectin structure image

Amylopectin structure

Branched

Amylopectin bonds

1,4 and 1,6 glycosidic bonds

Amylose structure image

Amylose structure

Unbranched

Amylose bonds

Only 1,4 glycosidic bonds

α glucose image

β glucose image

Glycogen structure

Branched

Glycogen bonds

α 1,4 glycosidic bonds and α 1,6 glycosidic bonds

Which monomer of glucose is used for glycogen

Alpha glucose

Callose image structure

Callose monomer

β glucose

Callose bonds

β 1,3 glycosidic bonds

Callose function

Deposited at plasmodesmata in times of stress to prevent pathogens from entering cells

Thin filaments within a myofibril are made of …. molecules

Actin

Actin molecules are ………….. molecules

Globular protein

Test for proteins

Biuret Test

Biuret test positive result

Colour change from blue to lilac/purple

Steps for biuret test

* are a liquid solution of the sample and treat with KOH to make the solution alkaline
* Add bieuret reagent

Test for lipids

Emulsion test

Emulsion test positive result

Milky emulsion will form on addition of water

Emulsion test steps

* dissolve in ethanol, shake to mix and then add water

Test for starch

Iodine

Iodine test positive result

Organelle/brown to blue/black

Name a non-reducing disaccharide

Sucrose

What monomers is sucrose made of

Alpha Glucose and fructose

Lactose monomers

Beta glucose and galactose

lactose glycosidic bond

1,4 glycosidic bond between galactose and glucose

Sucrose glycosidic bond

Alpha -1 beta- glycosidic bond

Maltose monomers

Glucose and glucose

Maltose enzyme

maltase

Trehalose monomers

two alpha glucose molecules joined by a 1,1 glycosidic bond

Trehalose is found in …

Insect and fungi

Is Trehalose reducing or non-reducing

Non-reducing

What are plant cell walls made of?

Cellulose

Ribosome function

Site of protein translation

RER function

folds and processes proteins that have been made at the ribosomes

RER description

A system of membranes enclosing a fluid-filled space, the surface is covered with ribosomes.

SER function

Synthesises and processes lipids

SER description

Like RER but without ribosomes

Mitochondrion shape

Oval shaped with a double membrane

Golgi body function

Processes an packages new lipids and proteins as well as making lysosomes

Vesicle function

Transports substances in and out of cell via the plasma membrane and between organelles.

Centriole function

Involved with the separation of chromosomes during cell division.

Centriole description

Small, hollow cylinders made of microtubules.Found in animals cells but only some plant cells

What are cilia and flagella made from

Microtubules

Protein pathway

mRNA is transcribes → out of nuclear pore → ribosome on R.E.R → Golgi body

4 functions of the cytoskeleton

* support organelles and their positioning
* Help to strength the cell and maintain its shape
* Transport organelles and material within the cell
* Cell cause the cell to move

Arrangement of microtubules in cilia

9 pairs around and 1 pair in the middle

Size of eukaryotic ribosomes

80S

Size of prokaryotic ribosomes

70S

Cell walls of fungi are made of

Chitin

Cell walls of plants are made of

Cellulose

Are prokaryote organelles membrane bound?

Prokaryotic organelles are not membrane bound

Magnification \=

Image size / object size

What unit must lengths be in when calculating magnification?

Doesn’t matter but all must be in the same unit

Mm to µm

X 1000

µm to nm

X 1000

Resolution is

How detailed the image is - or how well the microscope distinguishes between two pints that are close together.

Will increasing the magnification increase the resolution?

No

Light microscope maximum resolution

0.2µm

T.E.M maximum resolution

0\.0002 µm

Light microscope maximum magnification

X 1500