Unit 1-Area Of Study 1- Chapter 2-Ultrastructure Of Cells

Question 1

Microbial Mats

Answer 1

Composed of multilayers of a community of microbial species that can form
on moist or submerged surfaces including lakebeds, on sediments such as mud or sand, on tidal flats, in hypersaline (very salty) pools, in fissures, around hot springs and even around deep ocean vents

Question 2

Fossil

Answer 2

Evidence or remains of an organism that lived long ago

Question 3

Light Microscope

Answer 3

Microscope consisting of an optical instrument that magnifies the image of an object.

Question 4

Phase Contrast Microscope

Answer 4

Modified light microscope which enables transparent or unstained specimens, including living organisms, to be seen in more detail than can be obtained with a light microscope

Question 5

Laser Scanning Confocal Microscope

Answer 5

Technique for obtaining high-resolution optical images with depth selectivity. The key feature of confocal microscopy is its ability to acquire in-focus images from selected depths, a process known as optical sectioning.

Question 6

Fluorescence Microscope

Answer 6

Microscope in which cells are labelled with fluorescent probes and when irradiated with light of a particular wavelength, the probes are excited and fluoresce

Question 7

Scanning Electron Microscope(SEM)

Answer 7

Type of microscope that enables observation of cell and tissue surfaces

Question 8

Transmission Electron Microscope(TEM)

Answer 8

Type of
microscope that enables observation of very highly magnified images of cell sections; often abbreviated to TEM

Question 9

Resolving Power

Answer 9

Refers to the minimum distance apart that two points must be in order for them to be seen as two discrete points

Question 10

Resolution

Answer 10

Measure of the ability of a microscope to distinguish fine detail in a specimen; higher resolution means finer detail can be seen.

Question 11

STED nanoscopy

Answer 11

one of the techniques that make up Super-resolution microscopy. It creates super-resolution images by the selective deactivation of fluorophores, minimising the area of illumination at the focal point, and thus enhancing the achievable resolution for a given system

Question 12

Cytoskeleton

Answer 12

Network of filaments within a cell

Question 13

Cytosol

Answer 13

Fluid contents only of a eukaryotic cell

Question 14

Cytoplasm

Answer 14

Formed by cell organelles, excluding the nucleus, and the cytosol

Question 15

Chloroplasts

Answer 15

Chlorophyll-containing organelle that occurs in the cytosol of cells of specific plant tissues

Question 16

Vacuoles

Answer 16

Structures within plant cells that are filled with fluid containing materials in solution, including plant pigments

Question 17

Tonoplasts

Answer 17

A membrame separating the vacuole from the surrounding cytoplasm in a plant cell

Question 18

Proto Cells

Answer 18

One of the earliest cells on Earth

Question 19

Cell Wall

Answer 19

Semi-rigid structure located outside the plasma membrane in cells of plants, algae, fungi and bacteria

Question 20

Primary Cell Wall

Answer 20

The first layer of cellulose and other polysaccharides forming the cell wall outside a newly formed plant cell

Question 21

Cellulose

Answer 21

Complex carbohydrate composed of chains of glucose molecules; the main component of plant cell walls

Question 22

Secondary Cell Walls

Answer 22

Walls of lignin and cellulose
deposited on the primary cell wall of some plant
cells after cell growth has ceased

Question 23

Lignin

Answer 23

A complex insoluble cross-linked polymer

Question 24

Nucleus

Answer 24

In eukaryotic cells, membrane-bound organelle containing the genetic material DNA

Question 25

Nuclear Pore Complex

Answer 25

Protein-lined channel that
perforates the nuclear envelope

Question 26

Chromatin

Answer 26

Stained material in the nucleus of a eukaryotic cell

Question 27

Deoxyribonucleic Acid(DNA)

Answer 27

Nucleic acid containing the four bases — adenine, guanine, cytosine and thymine — which forms the major component
of chromosomes and contains coded genetic instructions

Question 28

Nucleoli/ Nucleolus

Answer 28

Structure present in
the nucleus and which is a store of ribosomal RNA
(rRNA)

Question 29

Ribonucleic Acid(RNA)

Answer 29

Type of nucleic acid
consisting of a single chain of nucleotide sub-units which contain the sugar, ribose and the bases A, U, C and G; RNA includes messenger RNA (mRNA), transfer RNA(tRNA) and ribosomal RNA (rRNA).

Question 30

Adenosine Trisphosphate(ATP)

Answer 30

Compound that is the common source of chemical energy for cells and whose structure comprises one adenosine molecule and three phosphate molecules

Question 31

Mitochondria

Answer 31

In eukaryotic cells, organelles that are the major site of ATP production

Question 32

Cellular Respiration

Answer 32

Process of converting chemical energy of food into a form usable by cells, typically ATP

Question 33

Ribosomes

Answer 33

Horizontal underground stems

Question 34

Endoplasmic Reticulum(ER)

Answer 34

Cell organelle consisting of a system of membrane-bound channels that transport substances within the cell

Question 35

Rough Endoplasmic Reticulum

Answer 35

Endoplasmic reticulum with ribosomes attached

Question 36

Smooth Endoplasmic Reticulum

Answer 36

Involved in transporting different materials within cells, but they are not passive channels like pipes

Question 37

Golgi Complex

Answer 37

Organelle that packages material into vesicles for export from a cell (also known as Golgi
apparatus or Golgi body)

Question 38

Autophagy

Answer 38

Breakdown by lysosomes of non- functioning cell organelles that are old and/or damaged and in need of turnover

Question 39

Lysosome Storage Disease

Answer 39

A disruption of normal
cell function due to defective enzymes; examples include Tay-Sachs disease, Hurler syndrome, Pompe disease

Question 40

Pompe Disease

Answer 40

An autosomal recessive condition—meaning that each parent of an affected individual must pass on a copy of the mutated gene. This is part of the reason that the disease is relatively rare, affecting 1 in 40,000 people.

Question 41

Tay Sachs Disease

Answer 41

An inherited metabolic disorder in which certain lipids accumulate in the brain, causing spasticity and death in childhood.

Question 42

Hurler Syndrome

Answer 42

Abnormal accumulation of complex
carbohydrates

Question 43

Peroxisome

Answer 43

Small membrane-bound organelle rich in the enzymes that detoxify various toxic materials that enter the bloodstream

Question 44

Photosynthesis

Answer 44

Process by which plants use the radiant energy of sunlight trapped by chlorophyll to build carbohydrates from carbon dioxide and water

Question 45

Chlorophyll

Answer 45

Green pigment required for photosynthesis that traps the radiant energy of sunlight

Question 46

Grana

Answer 46

(Singular = granum) stacks of membranes on which chlorophyll is located in chloroplasts

Question 47

Stroma

Answer 47

In chloroplasts, the semi-fluid substance between the grana which contains enzymes for some of the reactions of photosynthesis

Question 48

Cilia

Answer 48

(Singular = cilium) in eukaryote cells, whip- like structures formed by extensions of the plasma membrane involved in synchronised movement

Question 49

Flagella

Answer 49

(Singular = flagellum) whip-like cell organelles involved in movement

Question 50

Microtubules

Answer 50

Part of the supporting structure or cytoskeleton of a cell, made of sub-units of the protein tubulin

Question 51

Sessile

Answer 51

Fixed to one spot

Question 52

Endosymbiosis

Answer 52

A special case of symbiosis where one of the organisms lives inside the other

Question 53

Endosymbiosis Theory

Answer 53

See endosymbiosis, a theory proposed by Lynn Margulis