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What are eukaryotic cells?

cells with a nucleus and other membrane-bound organelles

what organisms have eukaryotic cells?

plants, animals, fungi, protists

What do plant cells have that animal cells don't?

chloroplast, cell wall, large vacuole

What do animal cells have that plant cells don't?

lysosomes and centrioles

What is a prokaryotic cell?

cell that does not have a nucleus or organelles

what organisms have prokaryotic cells?

Bacteria and Archaea

what are organelles

specialised structures within a cell that perform specific functions.

What is the nucleus?

membrane-bound organelle that contains a cell's DNA

What does the nucleus do?

regulates cell activities such as gene expression and cell division.

What is the cell membrane?

a thin barrier surrounding the cell that controls the movement of substances in and out.

What are lysosomes?

small organelles filled with digestive enzymes

What does a lysosome do?

Uses digestive enzymes to rid the cell of waste

what is DNA made up of

nucleotides

What does DNA stand for?

deoxyribonucleic acid

what does RNA do?

holds genetic information and aids in protein synthesis.

What is resolution?

the ability to distinguish separate points or objects in an image

if I have a higher resolution provides what?

provides clearer and more detailed images.

what does TEMs stand for?

transmission electron microscopes

How do TEMs work?

use electrons transmitted through a specimen to create detailed images, particularly useful for studying internal cell structures

What does SEMS stand for?

scanning electron microscopes

How do SEMs work?

scan the surface of a specimen with electrons to produce detailed three-dimensional images, allowing examination of surface features.

how are animal cells are distinct from those of other eukaryotic cells

because the lack cell walls and chloroplasts and have smaller vacuoles (meaning it can transform into a variety of different shape)

What does the cell membrane do?

controls what goes in and out of the cell

the cell membrane is

Semi-permeable/Partially permeable/Selectively permeable

What is the cell membrane made of?

phospholipid bilayer

What does semi-permeable mean?

It will let some molecules through but not others

what does hydrophilic mean

Attracted to water

What does hydrophobic mean?

repels water

what does glycoproteins mean

any of a class of proteins which have carbohydrate groups attached to the polypeptide chain

What is cholesterol?

a compound of the sterol type found in most body tissues

What does extrinsic mean?

not part of the essential nature of someone or something

Is DNA single or double stranded?

double helix

Is RNA single or double stranded?

single stranded

What are the four nucleotide bases found in RNA?

cytosine, guanine, thymine, uracil / c,g,t,u

Which nucleotide base pairs with uracil in RNA?

Adenine (A)

What is the role of uracil in RNA?

Uracil is responsible for pairing with adenine in RNA during the process of protein synthesis.

What are the four nucleotide bases found in DNA?

Adenine, Thymine, Guanine, Cytosine / a,t,g,c

What is a nucleotide?

the whole structure of a DNA

What is a polynucleotide?

long chain of nucleotides

What does condensation reaction make?

water

What is a hydrolysis reaction?

a reaction in which a bond is broken by the addition of a water molecule

which nucleotide bases join together In DNA

c=g

a=t

which nucleotide bases join together in RNA

C=G

A=U

What is magnification?

How much bigger the image is that the specimen

What is magnification calculation?

size of image / size of real object

How many micrometers are in a millimeter?

1000 micrometers

How many nanometer are in a micrometer?

1000 nanometers

Plant cells have

chloroplasts and a cell wall surrounding it

plant cells are distinguished from most other cells by

chloroplast and one or more Lange vacuoles

Where is chloroplast found?

in certain algae in plant cells

plant cells enable the vacuole to

attain a large size without accumulating the bulk that would make metabolism difficult.

Where is cell sap found inside plants?

Inside the vacuole

What is cell sap?

A water solution of sugar and salts

How is the high concentration of cell sap maintained?

The high concentration of cell sap is maintained by the active transport of ions through the vacuole membrane.

What role does active transport play in maintaining cell sap concentration?

Active transport of ions through the vacuole membrane helps to maintain the high concentration of cell sap.

What is osmosis?

diffusion of water across a selectively permeable membrane

pros of TEMs

* High resolution
* Highest magnification
* Gives information about surface features, shape, size and structure.

cons of TEMs

They're very big and expensive.

they are sensitive to mechanical vibration High maintains

Need a lot of materials in order to see anything

artifacts can be generated by sample preparation.

Special training is needed

Small space to see the material

pros of SEMs

* Can build 3d images
* sample does *not* need to thin
* Gives artificial colouring

cons of SEMs

* Artefacts are common
* Black and white image
* Specialist operators are required to operate electron microscopes
* Expensive
* inability to analyse live specimens

What is homeostasis?

Maintaining a stable internal environment

Examples of homeostasis

sweating and shivering

Homeostatic imbalances can lead to

diabetes, hypertension, and hypothermia.

what are the 5 things we need to keep a constant in our body

1. Water
2. glucose
3. Ph
4. body temperature
5. blood pressure

what happens when blood glucose is too high

Insulin is added and causes cells to take up more glucose

what does insulin do with the enzymes?

converts glucose to glycogen

What is glycogenesis?

formation of glycogen from glucose

what happens when blood glucose is too low

Glucagon is added

What does glucagon do?

activates enzymes in order to make glucose from glycerol and amino acids

What is gluconeogenesis?

the formation of glucose from glycerol and amino acids

Where does adrenaline come from?

adrenal gland

if blood glucose is too \____ Adrenaline is also secreted by adrenal glands

low

What is type 1 diabetes?

characterised by a lack of insulin production in the body, meaning high bsl

What is insulin?

Insulin is a hormone which converts glucose into glycogen (when blood sugar levels are too high)

Where does insulin come from?

pancreas

What is type 2 diabetes?

insulin resistance

how does the body try to deal with type 2 diabetes

the pancreas has to produce more insulin to try to regulate blood sugar levels,

Is type 1 or 2 diabetes more to do with lifestyle?

type 2

What is type 1 diabetes caused by?

an autoimmune attack on the insulin-producing cells in the pancreas

Is type 1 or type 2 diabetes less to do with lifestyle changes?

type 2

How is Type 2 diabetes managed?

diet and exercise

If you have glucose in your urine, what's responsible for it?

too much glucose

how can you detect if you have diabetes

urine dipstick

what is the kidneys' threshold for reabsorption

180 mg/dL

What is glycosuria?

glucose in the urine

What is osmoregulation?

The control of water balance.

How does the body lose water?

* sweat
* breathing out
* urine

What is aldosterone?

a hormone produced in the cortex of the adrenal gland

What does aldosterone do?

Increases reabsorption of sodium and increases secretion of potassium, this helps lower blood pressure

what are the consequences of Salt Deficiency

* Disorientation and Confusion
* Muscle Cramp and Nausea
* Severe Organ Damage
* Stroke

how do we lose too much salt

too much water - can flush out sodium

- excessive loss in body fluids

- eating disorder

What does ADH do?

Facilitates reabsorption of water in kidney

What is ADH?

antidiuretic hormone

Where is ADH produced?

hypothalamus and released by the pituitary gland

Where does aldosterone come from?

adrenal gland

What affects photosynthesis?

light intensity, carbon dioxide, water supply, temperature

Photon of light + water

1/2o2 +2e- + 2h+

What happens when photosystem 2 is hit with a photon of light?

When photosystem 2 is hit with a photon of light, it gets excited and releases 2 high-energy electrons.