Cell Structure: Key Words (Ms.D)

Question 1

What is a CARRIER PROTEIN?

Answer 1

-A PROTEIN on the CELL SURFACE
-That helps TRANSPORT MOLECULES and IONS across a PLASMA MEMBRANE

Question 2

What is CENTRIFUGATION

Answer 2

-Process of SEPARATING CELLS of diff SIZE and DENSITIES
-By SPINNING them at HIGH SPEEDS in a CENTRIFUGE

Question 3

What is a CHROMATID?

Answer 3

-1 of 2 COPIES of a CHROMO
-Joined together by 1 CENTROMERE PRIOR to CELL DIVISION

Question 4

What is CHOLESTEROL?

Answer 4

A LIPID that is an important component of CELL-SURFACE MEMBRANES

Question 5

What is a CHROMOSOME?

Answer 5

-THREAD-LIKE STRUCTURE made of PROTEIN & DNA
-Carries HEREDITARY INFO PHYSICALLY from 1 GEN to the NEXT

Question 6

What is DIFFERENTIATION?

Answer 6

Process of CELLS becoming SPEACIALISED for DIFF FUNCTIONS

Question 7

What is DIFFUSION?

Answer 7

-Movement of MOLECULES or IONS
-From a region of HIGH–>LOW CONC

Question 8

What is a EUKARYOTIC CELL?

Answer 8

A CELL that has MEMBRANE-BOUND NUCLEUS & CHROMOS

Question 9

What is FACILITATED DIFFUSION?

Answer 9

-Diffusion involving PROTEIN CARRIER molecules
-To allow PASSIVE MOVEMENT of SUBSTANCES across PLASMA MEMBRANES

Question 10

What is a GLYCOPROTEIN?

Answer 10

Substance made up of a PROTEIN molecule and a CARBOHYDRTAE molecule

Question 11

What is GRANUM?

Answer 11

-Stack of THYKALOIDS in CHLOROPLASTS that resembles a pile of coins
-Site of the LIGHT-DEPENDANT reaction PHOTOSYNTHESIS

Question 12

What is a GUARD CELL?

Answer 12

-1 PAIR of CELLS surrounding a STOMA in PLANT LEAVES
-CONTROLS OPENINGS and CLOSINGS

Question 13

What is a HIGH DENSITY LIPID (HDL)?

Answer 13

-A COMPOUND of PROTEIN & LIPID MOLECULES found in BLOOD PLASMA
-TRANSPORTS CHOLESTEROL from other CELLS–>LIVER

Question 14

What is an INTRINSIC PROTEIN?

Answer 14

-PROTEIN of CELL-SURFACE MEMBRANE
-SPAN the PHOSPHOLIPID BILAYER from 1 side to another

Question 15

What is an ION CHANNEL?

Answer 15

-PASSAGE across CELL-SURFACE MEMBRANE made up of PROTEIN
-OPENS & CLOSES to allow IONS to pass IN & OUT of CELL

Question 16

What is meant by the term ISOTONIC?

Answer 16

SOLUTIONS that possess SAME CONC. of SOLUTES and SAME WATER POTENTIAL as its comparison

Question 17

What is meant by the term IN VITRO?

Answer 17

Experiments performed outside of a living body

Question 18

What is meant by the term IN VIVO?

Answer 18

Experiments performed inside a living body

Question 19

What is a LOW-DENSITY LIPOPROTEIN?

Answer 19

-COMPOUND comprised of PROTEIN & LIPID MOLECULES that occurs in BLOOD PLASMA and LYMPH
-Carries CHOLESTEROL from LIVER–>other CELLS in BODY

Question 20

What is a MESOPHYLL?

Answer 20

-Tissue between 2 layers of EPIDERMIS in a PLANT CELL
-Comprised off PALISADE CELLS and a lower layer of SPONGEY CELLS

Question 21

What is the MIDDLE LAMELLA?

Answer 21

-Layer made of PECTINS and OTHER SUBSTANCES
-Found between WALLS of ADJACENT PLANT CELLS

Question 22

What are PALLISADE CELLS?

Answer 22

-LONG, NARROW cells packed with CHLOROPLASTS
-Found in the UPPER region of a LEAF & carry out PHOTOSYNTHESIS

Question 23

What is PHAGOCYTOSIS?

Answer 23

-MECHANISM by which a CELL ENGULFS PARTICLES
-To form VESICLES or VACUOLES

Question 24

What is the PHLOEM?

Answer 24

-PLANT TISSUE that TRANSPORTS products of PHOTOSYNTHESIS
-From LEAVES to rest of the PLANT

Question 25

What is a PHOSPHOLIPID?

Answer 25

TRIGLYCERIDES in which 1 of 3 FATTY ACID molecules is REPLACED by a PHOSPHATE molecule

Question 26

What is a PLASMID?

Answer 26

Small CIRCULAR piece of DNA found in BACTERIAL CELLS

Question 27

What is a PROKARYOTIC CELL?

Answer 27

A CELL that DOES NOT have a NUCLEUS or MEMBRANE-BOUND ORGANELLES

Question 28

What is a PROTOPLAST?

Answer 28

-The LIVING PORTION of a PLANT CELL
-I.E, The NUCLEUS and CYTOPLASM along with the ORGANELLES it contains

Question 29

What is a RECEPTOR?

Answer 29

A CELL ADAPTED to DETECT CHANGES in the environment

Question 30

What is the RECOGNITION SITE?

Answer 30

A NUCLEOTIDE sequence that is RECOGNISED by a RESTRICTION NUCLEASE which ATTACHES to it

Question 31

What is a SODIUM-POTASSIUM PUMP?

Answer 31

-PROTEIN CHANNELS across CELL-SURFACE MEMBRANES
-That use ATP to MOVE SODIUM IONS OUT of the CELL
-In EXCHANGE for POTASSIUM IONS that move IN

Question 32

What is a STEM CELL?

Answer 32

UNDIFFERENTIATED DIVIDING CELLS that occur in EMBRYOS and in ADULT ANIMAL TISSUES that require CONSTANT replacement

Question 33

What is the STOMA?

Answer 33

-A PORE, mostly in the LOWER EPIDERMIS of a LEAF
-Which GASES DIFFUSE IN & OUT of the LEAF

Question 34

What is the STROMA?

Answer 34

-MATRIX of CHLOROPLASTS
-Where PHOTOSYNTHESIS takes place

Question 35

What is SUPERNATENT LIQUID?

Answer 35

-LIQUID portion of MIXTURE left at the top of the tube
-When SUSPENDED PARTICLES have been SEPARATED out at BOTTOM during CENTRIFUGATION

Question 36

What are the THYKALOID?

Answer 36

-SERIES of FLATTENED MEMBRANOUS SACS in a CHLOROPLAST
-That contain CHLOROPHYLL and associated molecules needed for PHOTOSYNTHESIS

Question 37

What is a TISSUE?

Answer 37

-A group of SIMILAR CELLS
-Organised into a STRUCTURAL UNIT that serves a PARTICULAR FUNCTION

Question 38

What is a TRIGLYCERIDE?

Answer 38

Individual LIPID molecule made up of a GLYCEROL molecule and 3 FATTY ACIDS

Question 39

What is ULTRAFILTRATION?

Answer 39

Filtration assisted by BLOOD PRESSURE

Question 40

What are VOLTAGE-GATED CHANNELS?

Answer 40

-PROTEIN CHANNELS across a CELL-SURFACE MEMBRANE
-That OPENS & CLOSES according to changes in ELECTRICAL POTENTIAL across the membrane

Question 41

What is a XEROPHYTE?

Answer 41

A PLANT adapted to living conditions in DRY CONDITIONS

Question 42

What are XYLEM VESSELS?

Answer 42

-DEAD, HOLLOW ELONGATED TUBES with LIGNIFIED WALLS and NO END WALLS
-That TRANSPORT WATER in MOST PLATNS