Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Module 2: Foundations in Biology > 2.1.1 Cell Structure > Flashcards

2.1.1 Cell Structure Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

A)What are the microscopes you need to know

A
  • light/optical microscopes
  • Transmission electron microscopes
  • Scanning electron microscopes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

A)what does a light ( optical ) microscope do

A
  • they helps to understand cell structure
  • optical microscopes uses light (wavelength 400-700 nm) which is focused by glass.
  • the photo of the image produced is called a photomicrograph
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

A) what are the advantages of using a light / optical microscopes

A
  • linear magnification (x50 means 50 times larger)
  • cheap
  • easy to use
  • portable
  • stains are not necessary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A) what are the disadvantages of a light/optical microscope

A
  • limited resolution so some organelles cannot be seen ( eg ribosomes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A) how does a transmission electron microscope work

A
  • a beam of electron ( wavelength 0.004nm) from a cathode passes through the specimen and are focused by magnets onto a screen/photographic plate
  • produces a 2B black and white photomicrograph
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A) what are the advantages to transmission electron microscopes

A
  • very high magnification ( x2 000 000 max)
  • 0.1 nm resolution
  • Ultrastructure seen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

A) what are the disadvantages of transmission electron microscopes

A
  • large
  • expensive
  • needs skills and training to use
  • specimen needs to be in a vacuum
    -specimens needs to be dehydrated and stained with metal salt (may be dangerous)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A) How does a scanning electron microscope work

A
  • use of a beam of electrons from a cathode ( 0.004nm wavelength) that bounces of a specimen and then focussed by magnets.
  • this makes a 3D black and white electron micrograph ( colour can be added by computer)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A) what are the advantages of using a scanning electron microscope

A
  • high magnification achieved (x15 - x200,000)
  • 0.1 nm resolution
  • whole specimen can be used
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A) what are the disadvantages of scanning electron microscopes

A
  • large
  • expensive
  • need skill and training to use
  • cannot be used to study living organisms
  • specimen needs to be viewed while in a vacuum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

B) how do you prepare the wet mount slide for light microscopes

A
  • place a drop of water on the slide
  • place your sample specimen in your drop of water
  • set a cover slip over the sample specimen at a 45 degree angle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

B) how do you prepare the stained slides for light microscopes

A
  • Set a cover slip over the sample specimen at a 45o angle.
    -Place 1 drop stain on the other side of the cover slip.
    -The staining agent will begin to seep under the cover slip as the paper towel draws water out from the other side.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

B) what and how does an eye piece graticule work

A
  • an eye piece graticule is a small transparent ruler used to see the size of the object you are looking at
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

B) what is a stage micrometre

A

a microscope slide with a slide divided scale marked on the surface used to calibrate the eye piece graticule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

(c) what are stains

A

stains are coloured chemicals that bind to molecules which allows the different structures in specimens to become more visible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(C) what is meant by differential staining

A

using different stains which are used so different tissues are stained different colours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the conversions between cm, mm, micrometres, nanometres

A

cm -> mm x10
mm -> micrometre x1000
micrometre -> nanometres x1000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what should biological drawing include and not include

A

Biological drawings should not:
Include shading or colouring
Include arrow heads for labels
Involve lines overlapping each other

Biological drawings should:
Include a title
State the magnification or scale
Be drawn with a sharp pencil
Include smooth, continuous lines
Include labels
Include accurate sizes of observable structures

19
Q

what is the magnification formula

A

image size= magnification x actual size
i = am

20
Q

define resolution

A

Resolution is the ability to distinguish between two separate points (or how detailed the image is).

21
Q

define magnification

A

Magnification is how many times larger an image is than the object.

22
Q

what are the components of a eukaryotic cell

A

-nucleus
-nucleolus
-nuclear envelope
-rough and smooth endoplasmic reticulum (ER)
-Golgi apparatus
-ribosomes
-mitochondria
-lysosomes
-chloroplasts
-plasma membrane
-centrioles
-cell wall
-flagella
-cilia

23
Q

what are eukaryotes

A

multicellular organisms made up of eukaryotic cells like animals, plants, fungi, and protists.

24
Q

what are prokaryotes

A

These are single-celled organisms made up of prokaryotic cells like bacteria.

25
Q

what is the structure and function of the nucleus, nucleolus and nuclear envelope

A

Animal+plant
Structure
- surrounded by a nuclear envelope ( double membrane) containing pores
- contains genetic information in the form of chromosomes
- contains the nucleolus

Function
- Controlling the cell’s activities - It contains DNA with instructions to produce proteins.
- Synthesis of ribosomes - The nucleolus makes ribosomal RNA
- substances can enter and leave the nucleus via the pores in the nuclear envelope
- stores organisms genome and transmits genetic information

26
Q

what is the structure and function of the rough endoplasmic reticulum

A

animal+plant
Structure
- a system of membrane with fluid-filled cavities ( cisternae) that is continuous with the nuclear envelope and is coated with ribosomes

function
- RER is used as a transport system where ribosomes make the proteins and the cavities transport the proteins
- provides a large surface area for the ribosomes for protein synthesis

27
Q

what is the structure and function of the smooth endoplasmic reticulum

A

animal+plant
Structure
- system of cisternae continuous with the nuclear envelope but no ribosomes
- contains enzymes that catalyse reactions involved with lipids

Function
- used for the synthesis, storage and transport of lipids and carbohydrates
- for example: cholesterol and steroid hormones

28
Q

what is the structure and function of the Golgi apparatus

A

animal+plant
Structure
- contains fluid filled, membrane bound sacs know as cisternae, and contains smaller vesicles
- the vesicles being substances to and from the Golgi apparatus

Function
- Process and package lipids and proteins - Carried out by the cisternae.
-Store and transport lipids and proteins - Carried out by the vesicles.
-Synthesise lysosomes - Specialised vesicles.

29
Q

what is the structure and function of the ribosomes

A

animal+plant
Structure
- made up of proteins and ribosomal RNA
- consists of a large and small subunit
- not surrounded by a membrane

Function
- site of protein synthesis - involved in the process of translation

30
Q

what is the structure and function of the mitochondria

A

animal+plant
Structure
- contains an enzyme - rich liquid known as the matrix
- surrounded by a double membrane in which the inner membrane is folded to form structures known as cristae
- contains their own DNA and ribosomes

Function
- site of aerobic respiration - produces ATP

31
Q

what is ATP used for

A

it is used for energy in process such as ion transport, muscle contraction and nerve impulse propagation

32
Q

what is the structure and function of lysosomes

A

Animal
Structure
- Round organelles with no clear internal structure
- contains hydrolytic enzymes
- surrounded by a membrane to keep enzymes separate from the cytoplasm of the cell

Function
- Digest pathogens - using enzymes
- break down waste material ( including old organelles and cells)

33
Q

what is the structure and function of chloroplast

A

plant
Structure
-found in the green parts of plants
- contains fluid - filled sacs known as thylakoid which are stacked up to form grana
- surrounded by a double membrane, enclosing a fluid known as stroma
- contains its own DNA and ribosomes

Function
- a site of photosynthesis - reactions take place in the grana and stroma

34
Q

what is the structure and function of the cell surface membrane/ plasma membrane

A

animal+plant + bacteria
Structure
- found on the surface of animal cells
- mainly made up of lipids and proteins

Function
- controls the movement in and out of the cell as the membrane is partially permeable
- cell signalling - receptors can detect signals from other cells

35
Q

what is the structure and function of centrioles

A

animal
Structure
- they are hollow cylinders containing a ting of microtubules arranged at right angles to each other
- spindle fibres form the centrioles

Function
- involved in cell division, when the cell is dividing the centrioles go to opposite ends of the nucleus

36
Q

what is the structure and function of the cell wall

A

plant + bacteria
Structure
- made up of cellulose
- contains channel ( gaps_ known as plasmodesmata

Function
- supports the cell, contents of the cell press against the cell wall to make it rigid
- prevents the cell from bursting as the cell wall can withstand high osmotic pressure
- allows exchange of substances between cells as the channels connects to neighbouring cells

37
Q

what is the structure and function of the vacuole

A

plant
Structure
- Contains cell sap ( salt and sugar solution)
- surrounded by selectively permeable membrane known as tonoplast

Function
- Helps to maintain pressure within then cell, which keeps the cell rigid and stops the plant from wilting

38
Q

what is the structure and function of the flagella

A

Bacteria
Structure
- a long, hair - like structure

Function
- attached to the cell membrane and rotates to push the cell around its environment

39
Q

what is the structure and function of the cilia

A

animal
Structure
- protrusions from the cell surface membrane containing microtubules

Function
- to sweep substances along

40
Q

what is the relationship between some o the organelles involved in the production and secretion of protiens

A
  • mRNA copy of the gene is made in the nucleus and leaves via the nuclear envelopes nuclear pores
  • the mRNA attaches to a ribosome connected to RER
  • the ribosome reads instructions to assemble amino acid chains
  • proteins are then transported from the RER to the golgi apparatus in vesicles.
  • they are then modified in the Golgi apparatus
  • vesicles pinched off to the plasma membrane where it fuses with the membrane and the contents are releases via exocytosis
41
Q

what is the cytoskeleton

A
  • it is present in the cytoplasm and gives structure and support to the cell
42
Q

what is the importance of the cytoskeleton

A
  • made of microfilaments which is involved in cell movement and locomotion such as muscle contraction
  • made of microtubules which form a scaffold structure throughout the cell and acts as tracks for intracellular transport of vesicles and organelles
  • made of intermediate filaments which is responsible for the mechanical strength of certain tissues such as skin and hair
43
Q

what are the similarities and differences in structure and ultrastructure of eukaryotic and prokaryotic cells

A

Organism
prokaryotes - bacteria cells
eukaryotes - animal, plant

size
prokaryotes - 0.1 - 0.5 micrometres
eukaryotes - 10 to 100 micrometres

DNA
prokaryotes -circular DNA free in the cytoplasm
eukaryotes - linear DNA in the nucleus

Ribosomes
prokaryotes - smaller ribosomes (70s ribosomes)
eukaryotes - bigger ribosomes (80s ribosomes)

Organelles
prokaryotes -contains a few non membrane-bound organelles
eukaryotes - contains membrane-bound and non-membrane bound organelles

Cell walls
prokaryotes - made up of murein
eukaryotes - made up of cellulose (plants) or chitin ( fungi)

Biology Module 2: Foundations in Biology (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions