2 - Basic Component of Living Systems Flashcards
What is the role of the rough endoplasmic reticulum?
(Ribosomes bound to outside)
Synthesis and transport of proteins
What is the general structure of endoplasmic reticulum?
- network of membranes
- enclosing sacks called cisternae
- connected to the membrane of the nucleus
What is the role of the smooth endoplasmic reticulum?
carbohydrate and lipid synthesis and storage
Describe the structure of the mitochondria
- double membrane
- inside membrane folded into cristae
- filled with a fluid called a matrix
- cristae contain enzymes needed for aerobic respiration
Describe the role and structure of vesicles
- membraneous sacks
- single membrane filled with fluid
- storage and transport roles
-Where are lipids and carbohydrates synthesised?
smooth endoplasmic reticulum
Where are proteins synthesised and transported from?
Rough endoplasmic reticulum
Which organelle produces ribosmomes
Nucleus (in nucleolus)
Define metabolism. Give 3 examples.
All the chemical reactions that take place within a cell
- respirations
- photosynthesis
- protein synthesis
Define metabolite
A necessary or essential part of metabolism
The nucleus is surrounded by what structure? Why?
Nuclear envelope
-protects from damage from the cytoplasm
What is the structure fo the golgi appartus
- similar to SER
- compact
- formed of cisternae
- cis face (receiving vesicles)
- trans face (expelling vesicles)
How is DNA transported in and out of the nucleus?
Transcribed into RNA so it is small enough to be exported through pores in the nuclear envelope
What is the role of the mitochondria?
- final site of respiration
- energy from bonds in organic molecules converted to ATP
Describe the structure of the nuclear envelope
- contains pores to allow molecules to move in and out
- surrounds the nucleus - protects it from damage
Where are proteins synthesised?
Ribosomes
How does an SEM microscope work?
Bounces electrons off the sample for a 3D image
Define TEM
Transmission Electron Microscope
Define SEM
Scanning Electron Microscope
Give 2 advantages of a TEM microscope
- best mag (about 500,000x)
- best res (0.5nm)
Give one advantage of an SEM microscope
produces a 3d image
What is the function of the nucleus?
- contains coded genetic information
- directs the synthesis of proteins
What are lysosomes and what are their roles?
- specialised forms of vesicles (membraneous sacs)
- Carry hydrolytic enzymes to catalyze hydrolysis reactions
- responsible for breaking down waste
What is the structure of ribosomes? What are their roles
- found in the cytoplasm or attached to the RER
- made of RNA molcules
- NOT membrane bound
SITE OF PROTEIN SYNTHESIS
How does a TEM microscope work?
Fires electrons through sample
What is a dry mount and how is it prepared?
- solid whole specimens
- sectioned and placed on slide
What is a wet mount?
Specimen suspended in oil or water
What are 2 advantages of wet mounts?
- can be seen in motion
- more detail (oil)
How do you prepare a smear slide adn what would you use it for?
- use edge of slide to spread a thin layer of specimen
- eg. blood
How would you prepare a squash slide?
- wet mount prepared
- covered with slip and pressure applied from above
What is differential staining useful?
Able to distinguish between 2 types of organism
In microscopy, what is contrast?
The difference in shade between 2 objects
What is resolution?
The smallest distance between two objects that can be seen as seperate
Explain how diffraction limit resolution (5)
Diffraction happens when light passes through an object This causes rays to spread out Light rays overlap Objects not seen as separate Causes blurring
Outline the basic concepts of cell theory
Cell is basic unit of life
Both animal and plant tissue is made from cells
Cells only develop from existing cells
Describe the role of the two different lenses in compound microscopes and why they are present
Objective lens - magnifies sample
Eye-piece lens - magnifies image from eye-piece lens
Combined, this gives a large overlap magnification
