6.4 The organisation and specialisation of cells

Question 1

specialisation and function of eythrocytes

Answer 1

specialisation/ structure:
> biconcave shape to increase surface area for diffusion and increase cell flexibility to fit through narrow capillaries
> no nucleus so more space to hold haemoglobin to increase transport of oxygen

Function:
> transportation and exchange of gases between lungs and tissue

Question 2

specialisation and function of neutrophils

Answer 2

specialisation/ structure:
> flexible so can surround pathogens and engulf them
> contain lysosomes filled with hydrolytic enzyme lysozyme
> neutrophils made from stem cells in bone marrow
> lobed nucleus and granular cytoplasm

function:
> prevent infection by attacking and killing disease causing microbes

Question 3

specialisation and function of sperm cells

Answer 3

structure:
> flagellum to enable sperm cells to move to egg (which contains lots of mitochondria which provide the energy to make the cell move)
> the head the cell contains digestive enzymes to digest wall of egg cell

function:
> so sperm can penetrate and fertilise egg cell

Question 4

specialisation and function of palisade cells

Answer 4

specialisation/ structure:
> rectangular tightly packed cells that contain many chloroplasts to absorb light energy for photosynthesis
> thin cell walls to reduce diffuse distance of carbon dioxide

function:
> absorb and maximise light energy for photosynthesis

Question 5

specialisation and function of guard cells

Answer 5

structure:
> flexible walls more so on one side so cells can bend when turgid to open stomata and close when flaccid

function;
> helps control water loss by transpiration

Question 6

specialisation and function of squamous epithelial cells

Answer 6

structure:
> single layer of flat cells provides short diffusion distance

function:
> outline cells

Question 7

specialisation and function of ciliated epithelial cells

Answer 7

ciliated epithelial cells:
> hair like projections that sway to move substances such as mucus out of the lungs or an egg in oviduct
> goblet cell also located in the epithelium that release mucus to trap molecules eg dust
function:
> synthesise and secrete mucus

Question 8

specialisation and function of cartilage

Answer 8

cartilage:
structure:
> connective tissue that is firm and flexible located in outer ear nose and end of bones
> provides structural support and prevents bones from rubbing together which could damage them

shock absorber

Question 9

specialisation and function of muscle

Answer 9

structure:
> skeletal muscles cause skeleton to move
> Made up of myofibrils containing proteins actin and myosin
> smooth muscle located in organs and cardiac muscle within the heart
> muscles have multiple fibres connecting with tissues in between them
function:
> composed of tissue that can contract and relax to create movement

Question 10

specialisation of root hair cells

Answer 10

they have long extensions called root hairs which increases the surface area of the cell this maximises water and mineral uptake

Question 11

specialisation and function of xylem

Answer 11

Xylem:
Structure:
> tissue made up of elongated hollow dead cells
> lignin in walls to strengthen and waterproof walls
> xylem tissues made from stem cells in meristem

function:
> cells that make up the vascular bundle in plants responsible for transporting water and mineral ions

Question 12

specialisation and function of the phloem

Answer 12

structure:
> sieve tube elements that have perforated end walls
> lacks most organelles to make transport for sugars easier
> companion cells have organelles to provide resources for sieve tube elements
> phloem tubes made from stem cells in meristem

Question 13

specialisation of the epidermis

Answer 13

its got a thick waxy cuticle to prevent water loss got stomata controlled by guard cells to control water and CO2 loss, it has thin cells packed closely together