B1.1 - Cell Biology

Question 1

parts of animal cell

Answer 1

mitochondria
nucleus
cytoplasm
ribosome
cell membrane

Question 2

parts of plant cell

Answer 2

mitochondria
nucleus
cytoplasm
ribosome
cell membrane

cell wall
chloroplast
amyloplast - starch grain
vacuole

Question 3

Nucleus

Answer 3

controls activities of cell, contains genetic material

Question 4

Cell Membrane

Answer 4

barrier that controls what goes in and out of the cell - contains receptor molecules

Question 5

Cytoplasm

Answer 5

jelly-like substance, cells chemical reactions occur here

Question 6

Cell Wall

Answer 6

surrounds cell - made of tough fiber called cellulose. makes wall rigid and supports the cell

Question 7

Chloroplast

Answer 7

made of green pigment - chlorophyll, only in green part of plant. Chlorophyll transfers sun energy to the plant as light - used in photosynthesis

Question 8

Vacuole

Answer 8

full of cell sap, watery solution of sugars and salts. supports plant by keeping the cell rigid

Question 9

mitochondria

Answer 9

contain enzymes for respiration - where respiration happens

- enzymes enable glucose + O2 to react together

Question 10

Prokaryotes

Answer 10

• No nucleus genetic material floats in cytoplasm, often forms a ring - plasmid
• small (1-10μm)
• cell wall - peptidoglycan
• no mitochondria
• single-celled organism
• can have, flagella - movement, pili - attach to structures, slime capsules - protects cell
• examples - e.coli - food poising, streptococcus -sore throat

Question 11

Eukaryotes

Answer 11

• nucleus - contains gen material
• larger (10-100-μm)
• some have cell wall - cellulose
• mitochondria
• often made of many cells
• organelles surrounded by membrane
• examples - plants, animals, fungi

Question 12

Methylene blue

Answer 12

stains bacteria

Question 13

Iodine

Answer 13

stains carbs

Question 14

Crystal Violet

Answer 14

bacteria cell walls

Question 15

Magnification =

Answer 15

Image size / actual size

I / A x M

Question 16

Light microscope

Answer 16

• light rays - radiation used
• focusing with lenses
• magnification - X 1500
• resolution - 200nm
• living or dead biological matter
• small and portable
• easy to use
• quite cheap
• images produced in colour

Question 17

Electron microscope

Answer 17

• Electron beam - radiation used
• focusing with magnets
• magnification - X 500,000
• resolution - 0.2nm
• Dead biological matter
• Very large and static ( not easily moved)
• not easy to use - skill & training required
• very expensive
• samples in a vacuum
• images produced in black and white

Question 18

2 types of electron microscopes

Answer 18

• Transmission electron microscope ( TEM ) - sends electrons through a specimen, image produced is 2D
• Scanning electron microscope ( SEM ) - bounce electrons off surface of an object, images are 3D of the surface.

Question 19

Specialised cell

Answer 19

has a specific role, each specialised cell has a different role. Group of specialised cells = tissue

Question 20

Specialised cell examples

Answer 20

• red blood cells
• muscle cells
• ciliated epithelial cells
• fat cells
• sperm cells
• palisade cells
• root hair cells

Question 21

Stem cells in animals

Answer 21

• Embryonic stem cells - found in embryos, have ability to differentiate into all cell types
• Adult stem cells - found in tissues such as brain, bone marrow, skin and liver, can differentiate into SOME not all types of cells

Question 22

Stem cells in plants

Answer 22

• stem cells found in meristems which are in the roots and shoot tips and buds
• these stem cells have thin cell walls and small vacuoles compared to normal plant cells

Question 23

Conditions stem cells have potential to treat

Answer 23

• spinal chord injury
• diabetes
• heart disease
• Parkinson’s disease
• Alzheimer’s disease
• however, is controversial as it involves use of human embryos and can be used in cloning

Question 24

What sub-cellular structures do eukaryotic cells contain?

Answer 24

• mitochondria
• nucleus & nucleolus
• cytoplasm
• ribosomes
• cell membrane
• smooth and rough ER (endoplasmic reticulum)

Question 25

what bacteria causes sore throats?

Answer 25

streptococcus

Question 26

what sub-cellular structures does ALL bacteria contain?

Answer 26

• cell membrane
• cell wall
• cytoplasm
• genetic material

Question 27

stem cell definition

Answer 27

• a cell that hasn’t yet become specialised
• undifferentiated
• able to turn into many different cell types