B2 Cell Specialisation

Question 1

How many molecules of oxygen can haemoglobin contain

Answer 1

Four oxygen molecules

Question 2

When oxygen binds with haemoglobin it is called ……
When carbon dioxide binds it is called……

Answer 2

Oxyhemoglobin
Carboxyhaemglobin

Question 3

What three things do red blood cells lack and why?

Answer 3

Nucleus
Endoplasmic reticulum
Mitochondria

Why?
Larger space for haemoglobin
More efficient transport of oxygen

Question 4

What shape is a red blood cell and why is it this shape ??

Answer 4

Biconcave
A large surface area to volume ratio

Question 5

Why are red blood cells flexible??

Answer 5

Able to squeeze along narrow capillaries
Haemoglobin molecules are close to the cell membrane
Shorter diffusion distance of oxygen to the haemoglobin
Increased rate of diffusion across the cell membrane

Question 6

Why does a red blood cell have a thin membrane ?

Answer 6

Short diffusion pathway for oxygen and carbon dioxide
Gives cell flexibility

Question 7

What is a sperm cell and how many chromosomes does it contain?

Answer 7

A male gamete
23 chromosomes

Question 8

What is the head of the sperm cell called and what does it contain ?

Answer 8

Acrosome
Contains enzymes that help digest a path through the outer membrane of an egg cell

Question 9

What is in the mid section of a sperm and what does it do ??

Answer 9

Contains many mitochondria
The site of respiration
Provides energy to the cell to swim

Question 10

What is the tail of a sperm cell called and what is it used for??

Answer 10

Undulipodium
Gives the cell motility to deliver genetic information to the cell

Question 11

What is an egg cell called and how many chromosomes does it contain ?

Answer 11

Ovum
Contains 23 chromosomes

Question 12

What does an egg cell contain ?

Answer 12

Large cytoplasm
Organelles
An energy store

Question 13

What is the outer membrane of an egg called and what are its functions?

Answer 13

Zona pellucida

Hardens once the egg has been fertilised
Stops more than one sperm from entering

Question 14

Why does the egg cell have a lot of mitochondria??

Answer 14

Increased respiration for energy
Energy can be used for cell division, growth, protein synthesis

Question 15

What is the outer protective layer of an egg called and what are its functions?

Answer 15

Called the corona radiata
Supplies proteins to the egg once it has been fertilised

Question 16

The palisade mesophyll is a major site of….

Answer 16

Photosynthesis

Question 17

What shape are palisade mesophyll?

Answer 17

Cylindrical and are right angles to the epidermis of the leaf

Question 18

In a palisade mesophyll The cells are ……. Together and the gaps between them are to circulate……
And why?

Answer 18

Close
Air
Necessary for gas exchange

Question 19

In a palisade mesophyll the cell walls are made up of what and why?

Answer 19

Made up of thin, transparent cellulose walls
Gas diffusion is made easier

Question 20

why do Palisade mesophyll have a large surface area ?

Answer 20

Helps increase the rate of photosynthesis
Receives More sunlight
Makes the cell turgid
Pushes chloroplasts to the edge of the cell
Short diffusion distance for CO2 to get to the chloroplast

Question 21

What is the function of a root hair cell??

Answer 21

Absorb water from the soil to use for photosynthesis and other reactions
Absorb minerals from the soil

Question 22

Name all the structures in a root hair cell

Answer 22

Mitochondria
Thin cell wall
Long hair like extensions
No chloroplasts
Membrane permeability

Question 23

Why is the mitochondria needed ?

Answer 23

For active transport of solutes into the cell sap to lower water potential

Question 24

Why do root hair cells have a thin cell wall?

Answer 24

Shirt diffusion pathway for water and mineral ions

Question 25

Why do root hair cells have long hair like extensions ??

Answer 25

Increases surface area for absorption of water

Question 26

Why don’t root hair cells have chloroplasts

Answer 26

Not needed and gives more room for water storage and mitochondria

Question 27

Why do root hair cells have a membrane permeability

Answer 27

Selectively permeable to allow water molecules to enter easily fire this by possessing channels

Question 28

Where are white blood cells produced ?

Answer 28

Bone marrow

Question 29

What is the function of a white blood cell ?

Answer 29

To fight against infection/ cancer

Question 30

True or false All cells have antigens

Answer 30

True

Question 31

Why don’t our white blood cells attack our own cells??

Answer 31

This is bc our cells have antigens attached to them known as self antigens

Question 32

If our white blood cells do start attacking our own body what can this lead to?

Answer 32

An autoimmune disease where the body fails to recognise its own cells and attacks them

Question 33

Where are T cells produced in where di they mature and what are they involved in?

Answer 33

Bone marrow Thymus Specific immunity

Question 34

How do T cells work??

Answer 34

They detect cancerous cells or pathogens with an antigen receptor

Question 35

What are the three types of T cells and what do they do??

Answer 35

- helper - release cytotoxins that help regulate other white blood cells - cytotoxic - these release toxins to kill pathogens and cancerous cells -Memory cells - respond more quickly to a particular pathogen if it was to encounter it again

Question 36

What are the two types of B cells?

Answer 36

Plasma cells Memory cells

Question 37

What will the specific B cell divide into if there was a specific infection

Answer 37

Plasma cells

Question 38

What do plasma cells produce

Answer 38

They produce antibodies specific to the antigen

Question 39

What do antibodies do?

Answer 39

They don’t kill pathogens but they clump them all together making it easier for T cells and other white blood cells to find and destroy them

Question 40

What do B cells do to a virus

Answer 40

Bind to the virus and prevent them from entering a cell

Question 41

What is the most common type of white blood cell called and what is it involved in?

Answer 41

Neutrophils Non specific immunity

Question 42

What do neutrophils do and where are they produced?

Answer 42

They destroy invading microorganisms but do not give long term immunity Produced in the bone marrow

Question 43

Describe the structure of the neutrophils

Answer 43

Multi lobed shape in their nucleus Flexible Can squeeze through pores in the capillaries They contain a lot of lysosomes which have enzymes and these are used to destroy pathogens that have been engulfed

Question 44

What do neutrophils do in time of an infection

Answer 44

Special chemicals alert nature neutrophils through a person known as chemo taxis They leave the bone marrow and travel through the blood stream