cell structure and transport Flashcards
how many micrometers and nano meters are within one millimeter
1000 micrometers = 1 millimeter
1,000,000 nanometers = 1 millimeter
state the advantages of using a light microscope
light microscopes are cheaper
they are portable allowing for easy use in labs
they can magnify object by around 2000x
they can magnify live specimens
state differences between an electron microscope and a light microscope
electron microscopes are stuck in place (cannot be moved)
electron microscopes have a magnification of around 2 million times compared to a light microscopes 2000 x
electron microscopes give a 3D image
electron microscopes are expensive and need to be kept in a certain humidity,temperature and pressure to function
how do you calculate magnification
magnification can be calculated by multiplying all of the lenses used to enhance the image for example if the eyepiece lens is 4x and the objective lens is 10x then overall magnification is 40x
how do you calculate the size of the object when looking at it through a microscope
the formula magnification = image size/size of the real object can be used to calculate the sizes of the specimen you are investigating
what is resolution
resolution is the minimum distance between two points at which they can be distinguished as separate objects
what is the nucleus for
the nucleus is used to control all the activities within the cell and holds the cells genetic information. It carries the genes and chromosomes and the information for the proteins to make new cells
what is the cytoplasm for
cytoplasm is a liquid gel in which most of the chemical reactions needed for life are contained
what is the cell membrane
the cell membrane is the lining of the cell in which the passage of substances are controlled for example glucose and mineral ions are allowed to enter the cell and urea and hormones leave the cell
what is mitochondria
mitochondria are cellular structures where aerobic respiration takes place releasing energy for the cell
what are ribosomes
ribosomes are where protein synthesis takes place making the proteins for the cell
name the cellular structures of an animal cell
. nucleus
. cell wall
. mitochondria
. ribosomes
. cytoplasm
what are chloroplasts
chloroplasts are a cellular structure in plants that undergo photosynthesis and contain the green pigment chlorophyll that makes the plant leaf green
what is a vacuole
it is a space in the cytoplasm for storing cell sap whcih is needed to keep the cells rigid in the plant
what is a cell wall
it is a wall around the cell made of cellulose keeping it rigid and supports it
what are eukaryotic cells
animal and plant cells are eukaryotic as they have a cell wall ,membrane and DNA enclosed within the nucleus
what are examples of prokaryotes and what is their size in comparison to eukaryotes
bacteria and viruses are examples of prokaryotes and are 1-2 orders of magnitude smaller (10x-100x)
what are slime capsules
slime capsules add extra protection and support to the cell.
what are flagellum (flagella)
flagella are long strands made of protein. which allow the bacteria to move
where is the DNA within a prokaryotic bacteria cell
bacteria cells have free genetic material meaning that it is not contained within a nucleus and have extra strands of DNA called plasmids which contain very specific features such as antibiotic resistance