DP Biology vocab - cell biology (SL)

Question 1

Cell theory

Answer 1

theory that states that all organisms are composed of cells, and that all cells come from pre-existing cells.

Question 2

Homeostasis

Answer 2

the process in which an organism regulates activities within cells and their bodies to keep conditions stable.

Question 3

Magnification

Answer 3

ratio of image size to actual size.

Question 4

Metabolism

Answer 4

the sum of all of the chemical reactions that occur within an organism or within a cell.

Question 5

Cytoplasm

Answer 5

contents of a cell enclosed by the plasma membrane, not including the nucleus

Question 6

Cytoskeleton

Answer 6

a network of interlinking protein filaments and tubules present in the cytoplasm of cells

Question 7

Differentiation

Answer 7

the alteration of a cell’s morphology and physiology through changes in gene expression.

Question 8

DNA

Answer 8

a form of nucleic acid

Question 9

Electron microscope

Answer 9

microscope in which beams of electrons replace light so the magnification and resolution are much greater

Question 10

Endoplasmic reticulum

Answer 10

a system of membranes in the cytoplasm of eukaryotic cells formed of flattened sacs, existing as rough ER (with ribosomes) or smooth ER (without ribosomes)

Question 11

Eukaryote

Answer 11

cells with membrane-bound nuclei and organelles

Question 12

Fertilization

Answer 12

the fusion of male and female gametes to form a zygote

Question 13

Freeze-fracture

Answer 13

a technique that involves breaking apart a frozen biological sample to expose structural details for examination in an electron microscope

Question 14

Gene expression

Answer 14

the synthesis of a functional gene product, often protein, but also rRNA, tRNA, or snRNA.

Question 15

Golgi apparatus

Answer 15

a stack of flattened membranes, involved in processing, modifying and packaging of molecules

Question 16

Microvilli

Answer 16

tiny infoldings of the plasma membrane, making a “brush border”

Question 17

Mitochondria

Answer 17

organelle in eukaryotic cells, site of Krebs cycle and electron transport pathway

Question 18

Nucleoid

Answer 18

a region of the prokaryotic cell where DNA is located

Question 19

Organelle

Answer 19

a sub-cellular structure or membrane-bound compartment with a distinct structure and function

Question 20

Plasma membrane

Answer 20

membrane made of lipid and protein that forms the surface of cells

Question 21

Prokaryote

Answer 21

type of cell without a membrane-bound nucleus

Question 22

Stem cell

Answer 22

a relatively undifferentiated cell that can give rise to other types of cells and retains the ability to divide.

Question 23

Stem cell niche

Answer 23

specific microenvironment in the body that either maintain stem cells or promote their proliferation and differentiation

Question 24

Surface area to volume ratio

Answer 24

a variable that decreases as cells grow, so that it sets a limit to the size of cells.

Question 25

Vacuole

Answer 25

a fluid filled space in the cytoplasm, can be large and permanent in pant cells

Question 26

Vesicle

Answer 26

membrane-bound sac

Question 27

Histone

Answer 27

a protein associated with DNA that plays a role in gene expression and the packing of DNA

Question 28

Naked DNA

Answer 28

DNA not associated with histones

Question 29

Nucleus

Answer 29

membrane-bound organelle found in eukaryotes; contains DNA and is the site of DNA replication and transcription

Question 30

Eyepiece graticule

Answer 30

a graduated scale that is placed inside the eyepiece of the microscope, used as a ruler to measure lengths of structures

Question 31

Immunofluorescence microscopy

Answer 31

Uses antibodies fluorescently tagged to bind specifically to a corresponding antigen as a probe for identifying a particular molecule in cells, tissues, or tissues, or biological fluids

Question 32

Centrioles

Answer 32

a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.

Question 33

Aseptate fungi

Answer 33

Type of fungi with hyphae that is not partitioned by septa; multinucleated

Question 34

Skeletal muscle fibres

Answer 34

large nucleated structure, formed from many cells that fuse together to form a long fibre

Question 35

Phloem sieve tube elements

Answer 35

Made up of many cells joined end to end to form a long, hollow structure, used to transport sap

Question 36

Red blood cell structure

Answer 36

small flexible cell with no nuclei and few organelles, shape is biconcave

Question 37

Multipotent stem cells

Answer 37

stem cells that can become a limited number of types of tissues and cells in the body

Question 38

Pluripotent stem cells

Answer 38

Stem cells that can become almost all types of tissues and cells in the body.

Question 39

Totipotent stem cells

Answer 39

Stem cells that can differentiate into any type of specialized cells found in organisms of that species.

Question 40

Morphogen

Answer 40

a signaling molecule that flows between nearby cells and alters gene expression, causing cell differentiation in early-stage embryo