Cells Flashcards
What is the nucleus?
Controls activities of cell, contains genes that carry instructions for building new cells or organisms.
What is the cytoplasm?
A liquid gel in which organelles are suspended and where most of the chemical reactions take place.
What is the cell membrane?
Controls what goes in and out of the cell.
What are mitochondria?
Where aerobic respiration takes place releasing energy for the cell
What are ribosomes?
Where protein synthesis takes place. Making all the proteins needed for the cell.
What is a cell wall?
Made of cellulose that strengthens cell and gives support only found in plant cells.
What are chloroplasts?
Contains chlorophyll to make food by photosynthesis. Only found in plant cells.
What is the permanent vacuole?
Space in the cytoplasm filled with cell sap. Important for keeping cells rigid to support the plant.
What is the size of an average animal cell?
10-30 micrometres
What is the size of an average plant cell?
10-100 micrometres
What is the difference between an optical and electron microscope
Electron microscopes use beams of electrons instead of visible light to form highly magnified images.
What are prokaryotic cells?
Are single celled organisms. They are bacteria.are much smaller than eukaryotic cells. They have no nucleus.
What are eukaryotic cells?
Are evolved form prokaryotes. They are much longer and more complex. Unlike prokaryotic cells they contain a nucleus and organelles.
Equation for actual size
Actual size = image size/magnificatiom
Use of nerve cells?
Nerve cells carry electrical impulses around the body providing the communication between different parts of the body telling them what to do.
Has lots of dendrites to make connections with other cells
The nerve endings can pass impulses to other cells or muscles using special transmitter cells
Use of sperm cells?
Are the male gametes. Containing genetic information from the male parent.
Long tail to help sperm move
Middle section full of mitochondria
Nucleus contains genetic information
Use of muscle cells?
They work together in tissues to contract and relax to move the skeleton
Contain special proteins that slide over each other making the fibres contract and relax.
Use of root hair cells?
On tips of roots to help take up water and minerals more efficiently
Greatly increases surface area for water to move into cell
Large permanent vacuole to speed up movement of water by osmosis.
Use of xylem cells
Xylem carries water and mineral ions from the roots to the highest leaves and shoots. They are also important for supporting the plant
Spirals make the cell very strong allowing them to withstand pressure of water moving through the plant.
Use of phloem cells?
Transports food made by photosynthesis around the plant
Cell walls between the cells breakdown to form special sieve plates allowing water coming from dissolved food to move more freely.
