Organisation And Specialised Cells Flashcards
1
Q
What is a specialised cell
A
- cells in multicellular organisms are differentiated, meaning they are specialised to carry out very specific functions
2
Q
What is the structure and function of RBC
A
- the have a flattened biconcave shape, this increases their surface area to volume ratio
- this allows them to utilise and transport oxygen more efficiently
- they have no nuclei
- this allows them to fit more haemoglobin
- they are flexible so that they can fit through narrow capillaries
3
Q
Structure and function of neutrophil (type of white blood cell)
A
- they have a multi lobed nucleus which allows them to squeeze through small gaps to get to the site of infections
- the granular cytoplasm contains many lysosomes that contain enzymes used to attack pathogens
4
Q
Structure and function of sperm cell
A
- male gamete
- function to deliver genetic information to the female gamete
- they have a flagellum which is used to move and they have many mitochondria for the energy to move
- acrosome in the head contains digestive enzymes so it can digest protective layers around the ovum
5
Q
Structure and function palisade cells
A
- they are present in the mesophyll
- they contain chloroplasts for light absorption for photosynthesis
- rectangular shapes which allow them to be closely packed in continuous layer
- they have thin walls to increase CO2 diffusion rate
- they have large vacuole to maintain turgor pressure
- chloroplasts can move in the cytoplasm in order to absorb more light
6
Q
Structure and function of root hair cells
A
- present in the surfaces of roots near growing tips
- they have log extensions called root hairs
- these increase surface area of the cell to maximise uptake if water and minerals
7
Q
Structure and function of guard cells
A
- pairs of guard cells on the surfaces of leaves form stomata
- they are essential for CO2 to enter
- ## when guard cells lose water, osmotic pressure falls changing the shape of the guard cell and the stoma closes
8
Q
Structure and function of squamous epithelium
A
- made up of specialised squamous epithial cells
- very thin due to flat cells and because it is one cell thick
- it is present where rapid diffusion is needed
- it forms the lining of the lungs to allow oxygen diffusion into the blood
9
Q
Ciliates epithelium structure and function
A
- ciliated epithial cells
- cell have cilia on one surface that move rhythmically
- lines the trachea to waft mucus was from the lungs
- ## goblet cells are also present producing mucus to catch pathogens
10
Q
Structure and function of cartilage
A
- connective tissue found on the outer ear, nose, ends of and between bones
- it contains fibres of elastin and collagen
- firm, flexible connective tissue
- prevents the ends of bones from rubbing together
11
Q
Structure and function of muscle
A
- muscle needs to be able to shorten in length to move bones (move different parts of the body)
- different types of muscle fibres
- skeletal muscle (muscle attached to bone) contain myofibrils which contain contractile proteins
12
Q
Structure and function of epidermis
A
- single layer of closely packed cells in the surface of plants
- usually covered by a waxy water proof cuticle to prevent water loss
- contain stomata formed by guard cells which open and close
- they allow CO2, O2 and water in and out
13
Q
Structure and function of xylem tissue
A
- vascular tissue responsible for transport of water and minerals
- composed of vessel elements which are elongated dead cells
- the walls are strengthened with a waterproof material lignin, which provides structural support for plants
14
Q
Phloem tissue structure and function
A
- vascular tissue responsible for the transport of organic nutrients
- composed of columns of sieve tube cells separated by perforated walls called sieve plates
