Download B1.1 Fact sheet Cells

Fact sheet B2.1 Cells and tissues
Animal and plant cells
1. Are animal and plant cells eukaryotic or
prokaryotic?
2. Name the type of cell below
3. Identify the parts of the cell (5)
4. Name the type of cell below
5. Identify the parts of the cell (8)
Eukaryotic
Animal cell
1. Cell membrane
2. Mitochondria
3. Cytoplasm
4. Nucleus
5. Ribosomes
Plant cell
6. Cell Wall
7. Cell membrane
8. Cytoplasm
9. Mitochondria
10. Chloroplast
11. Nucleus
12. Ribosomes
13. Vacuole
6. Give the function of the cell membrane
7. Give the function of the nucleus
Controls the passage of substances into and out of
cells
Controls the activities of the cell
8. Give the function of the cytoplasm
Where most chemical reactions take place
9. Give the function of the mitochondria
Where energy is released from aerobic respiration
10. Give the function of the ribosomes
Where protein synthesis occurs
11. Give the function of the chloroplast
Absorb light energy to make food
12. Give the function of the vacuole
Filled with cell sap
13. Give the function of the cell wall and say
what it’s made of (2)


Strengthens the cell
Made of cellulose
Bacteria
14. Are bacteria cells eukaryotic or prokaryotic?
15. Name a type of single celled organism
16. Name the type of cell below
17. Identify the parts of the cell (5)
18. What do bacteria cells have instead of a
nucleus?
Specialised cells –animal cells
19. Give the 2 different ways that cells can be
specialised (2)
1. State how a sperm cell is specialised, and
explain how this enables it to carry out its
function/s (2)
2. State how a muscle cell is specialised, and
explain how this enables it to carry out its
function/s(1)
3. State how a ciliated cell is specialised, and
explain how this enables it to carry out its
function/s (2)
4. State how a red blood cell is specialised, and
explain how this enables it to carry out its
function/s (2)
Specialised cells –plant cells
5. State how a root hair cell is specialised, and
explain how this enables it to carry out its
function/s (3)
6. State how a leaf cell is specialised, and
explain how this enables it to carry out its
function/s (2)
Prokaryotic
Bacteria
A bacterial cell
1.
2.
3.
4.
5.
Genes NOT in a distinct nucleus
Cell wall
Flagellum (not always present)
Cytoplasm
Membrane
A single DNA loop and there may be one or more
small rings of DNA called plasmids
 Have a structure that other cells don’t (e.g.
sperm cell has a tail)
 They can have LOTS of a particular part (e.g.
muscle cells have LOTS of mitochondria)
–flagellum for movement to reach the egg
-lots of mitochondria for respiration to release
energy for flagellum to move
– lots of mitochondria for respiration to release
energy for muscle contraction
–cilia to move substances along tubes (e.g. egg
along oviduct, mucus out of airways)
-lots of mitochondria for respiration to release lots
of energy for movement of cilia
–full of haemoglobin so can carry lots of oxygen
-no nucleus so there is more space for haemoglobin
-has a large surface area so that it can absorb lots of
minerals and water
-long thin hair so it has a larger surface area to
absorb more of the substances it needs
-no chloroplasts because roots are below the
ground (don’t carry out photosynthesis), means
higher surface area for minerals and water
-lots of chloroplasts to carry out lots of
photosynthesis and produce lots of glucose
-lots of ribosomes to produce lots of protein
Microscopy
1. What are the two types of microscope?
2. Which microscope has a higher magnification
and resolving power?
3. What is the calculation for magnification?
4. Put the following measurements into size order,
starting with the smallest: mm, µm, nm, cm
5. What do the measurements above represent?
Mitosis and the cell cycle
1. Where are chromosomes found in a cell?
2. What are chromosomes made of?
3. Where are genes found?
4. What happens in the first stage of the cell
cycle? (3)
5. What happens in the second stage of the cell
cycle? (2)
6. What happens in the third stage of the cell
cycle?
7. How many cells are produced at the end of
mitosis?
8. What can you say about the cells produced
by mitosis?
9. Why is mitosis important for multicellular
organisms? (2)
Stem cells and differentiation
1. What is a stem cell?
2. What happens when a cell differentiates?
3. Why do cells differentiate during the development
of multicellular organisms?
4. Name the 2 places where human stem cells are
found
5. What could human stem cells potentially be used
for and why? (2)
6. When do most types of animal cells differentiate?
7. When do most types of plant cells differentiate?
8. What kind of tissue in plants can differentiate into
any type of plant cell, throughout the life of the
plant?
9. Why would we want to clone plants quickly and
economically?
-light microscope
-electron microscope
Electron microscope
magnification =
size of image
size of real object
nm, µm, mm, cm
mm = millimetre, µm = micrometre
nm = nanometre, cm = centimetre
In the nucleus
DNA
Large numbers on each chromosome
 The cell grows
 The number of organelles increases (e.g.
ribosomes and mitochondria)
 The DNA replicates
 MITOSIS –one set of chromosomes is pulled to
each end of the cell
 The nucleus divides
The cytoplasm and cell membranes divide (to
form two identical cells)
2
They are identical to each other
For growth and development
An undifferentiated cell which is capable of giving
rise to many more cells of the same type
It becomes specialised/ adapted to carry out a
specific function
To become specialised so that they can carry out
different functions
Embryos and adult bone marrow
 To treat conditions such as paralysis and diabetes
 As they can be made to differentiate into many
different types of cells, e.g. nerve cells
At an early stage
They retain the ability to differentiate throughout
life
Meristem tissue
 Rare species can be cloned to protect from
extinction
 Crop plants with special features (such as disease
resistance) can be cloned to produce large
numbers of identical plants for farmers
10. What is cell division mostly restricted to in
mature animals? (2)
11. What is produced in therapeutic cloning?
12. Why do we do therapeutic cloning?
13. Give an example of the potential risks that are
associated with the use of stem cells
14. Why might some people object to the use of
stem cells? (2)
• Repair of tissues
• Replacement of lost/ dead cells
An embryo with the same genes as the patient (a clone)
To obtain stem cells (from the embryo) that will not be
rejected by the patient’s body which means they can
be used for medical treatment
Transfer of viral infection
Ethical or religious objections
Diffusion, active transport and osmosis
1. How do dissolved substances move into and out of
cells across a cell membrane?
2. Define ‘diffusion’ (2)
3.
Name 3 factors that would affect the rate of
diffusion
4.
Give two examples of substances diffusing into and
out of cells by diffusion
5.
As organisms get larger the surface area to volume
ratio gets…
A single celled organism has a ________ surface
area to volume ratio. This allows for direct
________ of substances into and out of the cell. A
complex _______ ________ is not required to
meet the _____ of the organism.
Why do multicellular organisms need exchange
surfaces and a transport system?
6.
7.
8.
The effectiveness of an exchange surface is
increased by (4)
Diffusion
1. The net movement of particles in a gas or liquid
2. from an area of higher concentration to an area of
lower concentration.
 Concentration gradient (difference in
concentrations)
 Temperature
 The surface area of the membrane
 Oxygen and carbon dioxide in gas exchange
(between the lungs and the blood)
 Urea from cells into the blood plasma for excretion
in the kidney
smaller
Large
Diffusion
Transport system
needs
Because diffusion alone is not sufficient to meet the
needs of the organism as the surface area to volume
ratio is too small.
 Having a large surface area
 A membrane that is thin, to provide a short
diffusion path
 (in animals) having an efficient blood supply
 (in animals, for gas exchange) being ventilated
Two factors which cause organisms to need
specialised exchange surfaces are:
(2)
10. Two ways that dissolved substances can move
are:
(2)
11. Water moves across boundaries by:
■ increased size
■ increased complexity
12. Osmosis is the diffusion of water from a
_________ to a more ___________ solution
through a _________ ________ ________(4)
13. Differences in the concentrations of the
solutions ________ and _________ a cell
cause water to move
into or out of the cell by osmosis.
14. What is required to absorb a substance against
a concentration gradient?
(2)
15. A process which requires energy to move
substances is called?
16. Active transport enables cells
to absorb _______ from very dilute solutions.
In humans:
dilute (1)
concentrated (1)
partially permeable (1) membrane (1)
Inside and outside (1)
9.
■ diffusion
■active transport
Osmosis
Energy (1) from respiration (1)
Active transport
ions
17.
 the surface area of the lungs is increased by
the ____________
 the surface area of the small intestine is
increased by __________.
18. The villi provide a large surface area with an
extensive network of capillaries. What is their
function?
In plants:
19. What increases the surface area of
i) Roots
ii) Leaves
alveoli
villi
To absorb the products of digestion by diffusion
and active transport.
Root hairs
flattened shape and internal air spaces (2)