Flashcards in 1 - Cells and Organisation Deck (69):
Have a true nucleus (have a nucleus) and a cell membrane e.g.
Animal + Plant Cell
Have a false nucleus (no nucleus) Genetic material is usually kept freely in cytoplasm and they have no nuclear membrane e.g. Bacterial cells
Small ring of DNA usually found in Bacterial Cells
It Is a jelly like structure where most chemical reactions happen.
This controls what a cell does and contains all of the genetic information.
This is where most reactions for aerobic respiration takes place and also cellular respiration (breaking nutrients and turning them into energy).
This is where protein synthesis happens.
This gives protection and support to the cell e.g. Plant cell wall is made up of cellulose.
This contains cell sap which is a weak solution of sugar and salts.
Contains chlorophyll which absorbs sunlight during photosynthesis.
The random movement of particles from an area of high concentration to an area of low concentration.
A transport tissue in plants.It carries water and dissolved mineral ions from the root up to the leaves.
Is a transport tissue in plants.It carries dissolved food from the leaves around the plant.
Rate of Diffusion
How fast molecules will move from one place to another, the rate depends on the concentration gradient (how many particles there are) the temperature, surface area and the distance.
A special type of diffusion that only happens in water molecules it is when particles move from a low concentration (dilute solution) to a high concentration through a partially permeable membrane.
Multiply the magnification of the eyepiece lens by the magnification of the objective lens e.g. Eyepiece = x4 and Objective = x10 then your overall magnification is: 4x10=x40
Allows cells to move substances from an area of low concentration to an area of high concentration.This movement is against the concentration gradient.
Is the ability to distinguish between two separate points in an image and it is the resolving power of a microscope that affects how much detail it can show. E.g. A light microscope has a resolving power of about 200nm.
Order of Magnitude
Used to make approximate comparisons between numbers or objects.If one number is about 10 times bigger than another, it is an order of magnitude bigger.You show orders of magnitude using powers of 10.
E.g. A small animal cell has a length of around 10 micrometers.A large plant cell has a length of around 100 micrometers.
So, a large plant cell is an order of magnitude or 10 to the power of 1 bigger than a small animal cell.
Nerve cell adaptations
1)Lots of dendrites
2)An axon that carries the nerve impulse from one place to another.
3)Nerve endings or Synapses pass the impulses to another cell or between a nerve cell and a muscle in the body using special transmitter chemicals.
Muscle cell adaptations
1)Special proteins that slide over each other making the fibres contract.
2)Contain many mitochondria to transfer the energy needed for the chemical reactions that take place as the cells contract and relax.
3)Store Glycogen, which can be broken down and used in cellular respiration by the mitochondria to transfer the energy needed for fibres to contract.
Sperm cell adaptations
1)A long tail whips from side to side to help move the sperm through water or the female reproductive system.
2)Middle section filled with mitochondria, transfers energy needed for tail to work.
3)The acrosome stores digestive enzymes for breaking down the outer layers of the egg.
4)Large nucleus contains genetic information that needs to be passed on.
Root hair cells adaptations
1)Increase surface area available for water to move into cell.
2)Large permanent Vacuole that speeds up of water by Osmosis from the soil across the root hair cell.
3)Many mitochondria that transfer energy needed for the active transport of mineral ions into the root hair cell.
Cell is normal
A cell becomes plasmolysed when more water is lost via Osmosis, the vacuole and cytoplasm both shrink, and eventually the cell membrane pulls away from the cell wall.This is plasmolysis.
Bursting an animal cell by osmosis.
Shrinking an animal cell by osmosis
Turgor pressure makes the cells hard and rigid, which in turn keeps the leaves and stems of the plant rigid and firm.
Lots of particles
Low amount of particles.
Actual size = Image divided by Magnification
SA to V Ratio
E.g.Your intestines have more foldings so that the rate of diffusion is quicker.Also the vili in your lungs are made up of a single layer of cells.
This controls what goes in and out of the cell.
The phase in the life cycle of a cell where in the cell grows in size, replicates its DNA, and prepares for cell division.
Stores bile before releasing it into the duodenum
A substance produced in the liver. It emulsifies fats to prepare them for digestion.
Lipids include fats and oils and are found in foods such as butter, olive oil, and crisps. They are made of carbon, hydrogen and oxygen.
The production of identical offspring by asexual reproduction
A process where an embryo is produced that is genetically identical to the patient so then the cells can then be used in medical treatment.
Adult stem cells
Stem cells that are found in adults that can differentiate and form a limited number of cells.
The cell membrane pinches in and eventually divides into two daughter cells.
Have the ability to differentiate into another cell.
Are cells which have turned into other cells.
A group of specialised cells with a similar structure and function.
A group of organs that work together to carry out specific functions and form organs.
Biological catalysts, usually proteins.
A collection of different tissues working together to carry out specific functions.
The site on an enzyme where the reactants bind.
Fit into the active site. Once bound to the active site, the chemical reaction takes place.
Are enzymes that speed up the breakdown of proteins into amino acids.
Enzymes that speed up the breakdown of lipids into fatty acids and glycerol.
Enzymes that speed up the breakdown of carbohydrates into simple sugars.
The site on an enzyme where the reactants bind.
Is the liquid part of the blood and it is yellow in colour.
Red blood cells
Are biconcave cells that contain the red pigment haemoglobin and carry oxygen around the body in the blood.
White Blood Cells
Are involved in the immune system of the body.
They engulf pathogens and make antibodies and antitoxins.
Fragments of cells in the blood that play a vital role in the clotting mechanism of the blood.
Blood vessels that carry blood away form the heart. They usually carry oxygenated blood and have a pulse.
Blood vessels that carry blood away from the heart. They usually carry deoxygenated blood and have valves to prevent the back-flow of blood.
The smallest blood vessels. They run between individual cells and have a wall that is only one cell thick.
Double Circulatory System
The circulation of blood from the heart to the lungs is separate from the circulation of blood from the heart to the rest of the body.
The red pigment that carries oxygen around the body in the red blood cells.
Is a metal mesh placed in a blocked or partially blocked artery. The are used to open the blood vessel by the inflation of a tiny balloon.
Are electrical devices used to correct irregularities in the heart rhythm.
Reduce cholesterol levels in the blood, reducing the risk of coronary heart disease.
Adaptations of the alveoli:
The alveoli provide a very large surface area and a rich supply of blood capillaries. This means gases can diffuse into and out of the blood as efficiently as possible.
When you breathe in oxygen-rich air moves into your air.
This maintains a steep concentration gradient in the blood.
As a result, oxygen continually diffuses into your bloodstream through the gas exchange of the alveoli.