B1 - Cell Structure And Transport Flashcards
Formula of magnification?
Size of image/size of real object
What is the role of the Nucleus?
Contains the genetic information of the cell (chromosomes and DNA)
What is the role of Cytoplasm?
A solvent in which chemical reactions take place
Role of cell membrane?
It controls the movement of substances in and out of the cell
Role of mitochondria?
The place where aerobic respiration occurs, producing energy needed for the cell to survive and function and contains enzymes for cellular respiration.
Role of ribosomes?
Tiny structures where protein synthesis occurs.
Role of cell wall?
To provide the cell with structure and to protect all things within it.
Role of chlorophyll?
Enables photosynthesis to take place
Permanent vacuole role in the cell?
A permanent vacuole is a fluid-filled sac that stores water.
What are the components of an animal cell?
Nucleus, cell membrane, cytoplasm, mitochondria, ribosomes
What are the components of a plant cell?
Nucleus, cell membrane, mitochondria, ribosomes, cytoplasm, cell wall, chlorophyll, permanent vacuole
Two types of microscopes
Electron and Light microscopes
What are cells of bacteria called?
Prokaryotic cells
What are some examples of Eukaryotic cells?
Animal, plant and fungi cells
Diffusion
The net movement of particles from an area of high concentration to an area of low concentration
What sorts of substances move in and out of cells?
Includes simple sugars, such as glucose, gases such as oxygen, and waste products such as urea.
What is the effect of temperature on diffusion?
The higher the temperature, the faster the rate of diffusion.
Why is diffusion important for living organisms?
Because cells need to take in substances for respiration, and they also need to get rid of waste products/chemicals that are needed elsewhere for the body. The main way that they move is diffusion.
The effect of surface area on diffusion.
The larger the surface area, the faster the rate of diffusion
What is the effect of the concentration gradient on diffusion?
The greater the concentration gradient, the greater the rate of diffusion.
What is Osmosis?
The diffusion of water molecules from a dilute solution (high concentration of water) to a more concentrated solution (low concentration of water) across a partially permeable membrane.
Isotonic definition
An isotonic solution has the same concentration of solutes as the cell. In this case, there is no net movement of water across the cell membrane, and the cell will maintain its normal shape and size.
Hypotonic definition
Those in which the concentration of solutes is lower than that inside the cell. Water molecules move into the cell in hypotonic solutions, causing the cell to swell
Hypertonic definition
Hypertonic solutions are those in which the concentration of solutes is higher than that inside the cell. Water molecules move out of the cell in hypertonic solutions, causing the cell to shrink.
What happens if you place animal cells in a dilute solution?
They will take in water, therefore causing them to burst. This is called lysis, and the cells are now said to be lysed.
What happens if you place animal cells in a concentrated solution?
The animal cell will lose water, therefore causing them to shrivel. This is called crenation, and the cells are now said to be crenated.
What happens when you place a plant cell in a dilute solution?
The water will move into the cell, this causes the vacuole to swell. This causes high turgor pressure, and the cells are said to be turgid. As a result the plant will be rigid.
What happens when you place a plant cell in a concentrated solution?
The water will move out the cell, this causes the cell to shrivel. This causes low turgor pressure, and makes the cells flaccid. As a result, the plant will wilt.
Definition of turgor pressure
The force within the cell that pushes the plasma membrane against the cell wall.
Active transport
When cells need to move substances against the concentration gradient.
What is the opposite of diffusion?
Active transport
How much do light microscopes magnify?
1000 times
How much do electron microscopes magnify up to?
Up to 1 million times
Formula for surface area
Surface area of one face X total number of faces
