3.2 Chapter 3- Cell Structure Flashcards

Question

What are the functions of the Golgi apparatus? | Hint:

Answer 1

* Protiens and lipids produced by the endoplasmic reticulum pass through the Golgi * The golgi **modifies protiens** - adds non-protiens e.g. carbs to form glycoprotiens. * Modifies lipids- adds protiens- lypoprotien. * 'Labels' protiens- sorts them and sends to the right destination * **Packages protiens into golgi vesicles** which are pinched off from ends of cisternae to transport protiens * Forms lysosomes * Transports modifies and stores lipids

Answer 2

In secretary cells esp. epithelial cells

Answer 3

Answer on revision card.

Answer 4

* Fluid filled sac pinched from golgi cisternae- surrounded by membranes * In the cytoplasm

Answer 5

* Stores lipids and protiens * **Transports** lipids and **protiens** outside the cell and within the cell along with rough endoplasimic reticulum * **Fuses with cell membrane** to release contents

Answer 6

* Golgi vesicle with enzymes * Membrane bound * Contain lysozymes- hydrolytic enzymes that hydrolyse the cell walls of bacteria in the immune system

Answer 7

In secretary cells e.g. epithelial cells and phagocytes.

Answer 8

* Break down dead cells completely- autolysis * Digest worn out organelles into useful chemicals * Contain lysozymes- hydrolytic digestive enzymes- kept seperate by membrane- digest invaders and worn out organelles. * Isolate enzymes and release them outside the cell or into a phagocytic vesicle (phagosome) * Hydrolyse material ingested by phagocytes * Release enzymes outside the cell to destroy material

Answer 9

* No membrane * 80s- eukaryotes- larger * 70s- prokaryotes- smaller- prokaryotes and organelles * Made of ribosomal RNA and protiens * 2 subunits- one large and one small- both contain rRNA and protien

Answer 10

* In all cells * In cytoplasm or attatched to RER * Vast numbers in cells

Answer 11

Protien synthesis in translation.

Answer 12

* Elaborate 3D structure of sheet like membranes- lamellae * Membranes have fluid inside and enclose tubules and flatenned sacs called cisternae * Fluid inside * Continuous with the outer nuclear membrane

Answer 13

Has ribosomes on outer membrane.

Answer 14

* Folds and prcoesses protiens made in ribosomes * Large surface area for synthesising protiens * Transports materials especially protiens

Answer 15

No ribosomes on outer membrane

Answer 16

Synthesise, store, process and transport lipids and carbohydrates.

Answer 17

Answer on revision cards.

Answer 18

* Microfibrils of cellulose in matrix * Made of polysaccaride- cellulose. * Middle Lamella- marks boundary between cell walls and cements cell walls together

Answer 19

Mainly cellulose and glycoprotien?

Answer 20

Mainly Chitin and Glycoprotien

Answer 21

* Strength- stops cell bursting form water pressure. * Supports cell and plant * Microfibrils aid in strength * Stops cells changing shape * Permeable- allow water to pass along- contribute to water movement

Answer 22

* Fluid filled sac * Surrounded by a single membrane called a tonoplast * Mature cells have one large central vacuole * Contains cell sap- solution of sugars, amino acids, salts, wastes and pigments * In plants

Answer 23

* Makes the cell turgid- maintains pressure- keeps cell rigid and supports plants- stops wilting * Isolates unwanted chemicals * Temporary food store of amino acids and sugards * Pigments- attract polinators

Answer 24

* By looking at the number and size of organelles, * e.g., mitochondria and large number of cristae means a high metabolic rate.

Answer 25

* All cells perform basic functions. * After the embryo, cells become specialised to perform a specific function by switching genes on and off * Cell structures e.g. organelles help the function.

Answer 26

Evolbed so can function more efficiently so the whole organism can function.

Answer 27

Vary in shape, type, size and number

Answer 28

* Consider the role of the cell and what features it might need * e.g. epithelial cells- microvilli- increase surface area of cell-suface membrane- have lots of mitochondria for active transport and extensive endoplasmic reticulum for protien synthesis

Answer 29

* Cells * Tissues * Organs * Organ systems

Answer 30

* Group of cells working together to perform a function. * e.g. epithelial tissue made of epithelial cells line the surface of organs for protection.

Answer 31

* Made up a combination of tissues that have a variety of functions to help towards one major function. * e.g. Epithelial tissue and muscular tissue and glandular tissue from stomach.

Answer 32

Capillaries- tissue made of just one tissue vs arteries and veins which are organs.

Answer 33

* Organs that work together as a single unit to perform functions more efficiently. * e.g. digestive system

Answer 34

* Single celled organisms * Much smaller than eukaryotes. * No membrane bound organelles in the cytoplasm.

Answer 35

* Have a cell wall with murien (glycoprotein- protein and carbohydrate)- protects against damage and supports the cell * 70s- smaller ribosomes * No nucleus- circular DNA molecule that floats free in the cytoplasm not associated with proteins, especially histones- strand coiled up.

Answer 36

* Plasmids- one or more circular loops of DNA that contain e.g. antibiotic resistance genes and can be passed between prokaryotes. * Capsid- secreted slime that protects the prokaryote from the immune system. * Flagella- hair like structures that rotate to move the cell-one or more

Answer 37

Answer on revision card.

Answer 38

* Acellular (not cells) and non-living * Smaller than bacteria- 0.1 micrometers

Answer 39

* Nucleic acids- e.g. DNA/ RNA * Capsid- protien coat that encloses the protien * Lipid envelope- in some viruses * Attatchment protiens- stick out of lipid envelope/ capsid- allow viruses to identify and attatch to host cell.

Answer 40

Inside the host cell.

Answer 41

Answer on revision card.

Answer 42

* Also known as a light microscope. * Uses light and **glass lenses** to magnify the image and **focus**

Answer 43

* Resolution- 0.2 micrometres * Magnification- x1500

Answer 44

Small resolution and magnification. Can't see organelles smaller than 0.2 micrometres e.g. ribosomes **due to low resolution** due to **the wavelength of light being too long.**

Answer 45

Electron microscopes have a smaller wavelength than light microscopes.

Answer 46

1000x the resolution of light

Answer 47

x1,500,000

Answer 48

* Produces a black and white image * Sample has to be dead and in vacuum so particles don't block electrons.

Answer 49

Transmission Electron Microscope

Answer 50

* An electron beam is **focused** on the specimen using an **electromagnet**. * The electrons are transmitted through the specimen, and the denser parts absorb the electrons and less dense parts allow electrons to pass through. * Denser parts therefore appear darker and lighter parts appear lighter. * Creates a 2D image of a cross section that can be built up to form a 3D image

Answer 51

1 nanometre- highest of all microscopes.

Answer 52

* Specimen must be in a vacuum and **dead** * Complex staining process and **time consuming preparation** * **Thinner specimen** needed * Subject to more artefacts * Produces a black and white- **no colour**- image

Answer 53

Comparative language e.g. more, thinner, greater.

Answer 54

Scanning electron microscope

Answer 55

* Uses an electron magnet to focus a beam of Electrons over the surface of a specimen moving in a regular pattern to scan it * Scattering of electrons used to build image of contours * Builds a 3D image by computer of scattered electrons

Answer 56

* Doesn't need a thin specimin * Produces a 3D image

Answer 57

* Specimen must be in a vacuum and dead. * Black and white image. * Complex preparation process means more likely to gain artefacts. * Lower resolution than TEM

Answer 58

1. Use an eyepiece graticule- glass disc with scale attatched on eyepiece- usually 10mm 2. Calibrate the graticule using a stage micrometer (can't directly measure due to magnification- calibration often recorded so don't need to do second time) 3. A stage micrometer has a scale on it- usually 2mm- line up and count scales 4. Convert both into micrometers then find micrometers per eypeace graticule unit- divide micromiters by number of units above

Answer 59

* Use a scale factor * e.g. 40 to 400- divide by 10

Answer 60

The size of an image compared to the size of an object.

Answer 61

Magnification= size of image/ size of object

Answer 62

* How well a microscope distinguishes two points that are close together. * If objects are less than the resolving power- blurred together. * After the resolving point a higher magnification doesn't improve clarity * Measure of detail and clarity

Answer 63

Objects that are a result of how a specimen is prepared and not naturally part of the specimen.

Answer 64

* In electron microscopes as need a lot of preparation

Answer 65

Doing multiple repeats.

Answer 66

1. Use a temporary mountain e.g. water with a pippet. 2. Put thin specimen on drop with tweezers. 3. Add a stain 4. Add a cover slip with a mounted needle

Answer 67

Used to separate cell components (organelles) to study structure and function.

Answer 68

1. Cold- to reduce the enzyme activity and stop them breaking down organelles. 2. Isotonic- the same water potential to prevent organelles from bursting or shrinking due to osmosis. 3. Buffered- ensures no change in pH occurs that would alter organelle proteins.

Answer 69

* Homogenisation- place in homogeniser (blender)- bursts membrane and releases organelle. * Filter to remove large pieces and complete cells.

Answer 70

1. Place homogenate in centrifuge and spin at low speed 2. The densest organelles form to the bottom- as seperates organelles in order of density- form sediment or pellet 3. The rest of the organelles stay in fluid above called supernatant 4. Supernatant poured into new tube and spun at a higher speed- new pellet of different organelles 5. Supernatant drained off and repeated at high speeds until less dense and less dense organelles.

Answer 71

1. Nucelei 2. Chloroplasts 3. Mitochondria 4. Lysosomes 5. Endoplasmic reticulum 6. Ribosomes

Answer 72

* From other cells. * Through binary fission, mitosis or meiosis.

Answer 73

The cell cycle is needed for growth and repair to replace and add other cells.

Answer 74

Varies in time from cell to cell.

Answer 75

The ability to divide.

Answer 76

* Begins when cells are produced. * Ends with cell division.

Answer 77

* Most of the cell cycle- 90% * Growth and DNA replication, organelles and ATP increase * G1- cell grows and more organelles and protiens made. * S phase- replication of DNA * G2- more cell growth and protiens needed for cell division are made. * Cell carries out normal function and prepares to divide.

Answer 78

* DNA unravels and replicates twice * DNA ravelled and joined by the centromere.

Answer 79

Answer on revision card.

Answer 80

* Mitosis is the part of the cell cycle where cell division occurs. * After the G2 stage of interphase. * Results in two genetically identical daughter cells from a genetically identical parent cell.

Answer 81

* Two strands joined at the centromere. * Strands are called chromatids. and two identical strands are called sister chromatids. * Produced during interphase

Answer 82

1. Prophase- chromasomes condense and thicken. Centrioles (organelles) move to opposite poles of hte cell and form spindle fibres from pole to pole (collectively called spindle apparatus). Nucleolus disappears and nuclear envelope breaks down- chromasomes free in the cytoplasm. 2. Metaphase- spindle fibres line up chromasomes along the middle of the cell and attatch to the centromere of chromasomes with two chromatids. 3. Anaphase- centromere divide chromasomes into two seperate sister chromatids. Spindle fibres pull chormatids to opposite poles by the centromere. Energy provided by mitochondria. Chromatids become chromasomes. 4. Telophase- chromasomes reach opposite poles, uncoil, spindle fibres disintegrate, nuclear envelope and nucleolus reform. 5. Cytokinesis- cytoplasm divides- 2 genetically identical daughter cells.

Answer 83

Centrioles

Answer 84

Answer on revision card.

Answer 85

1. Put stage over total amount of cells 2. Multiply fraction by time

Answer 86

* Mitosis is controlled cell division by genes for growth and repair * Cancer is uncontrolled cell division and tumours resulting from mutated and damaged genes.

Answer 87

* Cancer is uncontrolled cell division and tumours resulting from mutated and damaged genes. * Most mutated cells die- few that survive cause tumours. * Uncontrolled division creates a tumour which expands * Tumour becomes a cancer when it turns from benign (slow growing and doesn't invade other cells) to malignant (invades surrounding tissue and fast growing)

Answer 88

* Directed at controlling rate of cell division and killing cells by disrupting cell cycle. * Chemotherapy- prvents DNA replicating, inhibits metaphase by destroying spindles * Drugs- stop G1 and enzyme synthesis for DNA replication causing the cell to self destruct. * Drugs and radiation- damage DNA- cell kills itself and can't replicate DNA.

Answer 89

* Drugs are more effective if cells divide rapidly. * As cancer cells divide quicker- more damage done to them than othe rcells. * Other rapidly dividing cells e.g. hair cells- vulnerable

Answer 90

Wear safety goggles, a lab coat and gloves.

Answer 91

1. Cut 1cm off the root tip- where mitosis occurs- put in boiling tube- add HCl so just covers, put in water bath of 60℃ and leave for 5 minutes. 2. Remove tip and rinse with water, leave to dry. 3. Place on slide and cut off 2 mm of very tip- use mounted needle to break up and spread thinly. 4. Add stain and add coverslip- push down with filter paper- squash don't smear. 5. Place slide on stage and clip in 6. Select the lowest magnification objective lens and use the coarse adjustment knob to bring hte stage just below the lens. Look through eyepeice and use coarse adjustment to move the stage down to focuse then focus more with fine adjustment knob. 7. Swap to higher magnifications and repeat.

Answer 92

1. Use relative size 2. Write down magnification and scale 3. Single lines and no shading 4. Label 5. Give title

Answer 93

* The proportion of cells undergoing mitosis * Used to work out how quickly a tissue is growing.

Answer 94

Number of cells with visible chromasomes/ number of cells observed

Answer 95

* Binary fission * Produces 2 daughter cells and replicates genetics

Answer 96

1. Circular DNA and plasmids replicate. Circular DNA has 2 copies whereas plasmids have many copies 2. The copies attatch to the cell membrane at opposite poles. 3. The cell membrane and cell get bigger. 4. The cell membrane begins to pinch in between the two DNA molecules dividing hte cell in two 5. A new cell wall is formed dividing the two original cells into two identical daughter cells with a single identical copy of circular DNA and a variable number of copies of plasmids.

Answer 97

* As viruses are non living, they do not undergo cell division. * They attatch to their host cells with attatchment protiens complementary to the receptor protiens on the host cell * They inject their nucleic acid (DNA or RNA) into the cell. * The cell then uses its metabolic processes following instructions from the nucleic acid to replicate viral particles to assemble viruses e.g. in ribosomes * The viruses then burst the cell once enough are made.

Answer 98

* Different viruses require different host cells due to specific attatchment and receptor protiens * Some viruses can only infect one type of cell * Other viruses can infect lots of types of cell.

3.2 Chapter 3- Cell Structure Flashcards

3.2.1- Cell Structure, 3.3.2- All Cells Arise from other cells (123 cards)