Organisation and specialisation of cells Flashcards Preview

Chapter 6 Cell Division > Organisation and specialisation of cells > Flashcards

Flashcards in Organisation and specialisation of cells Deck (19):

What are differentiated cells?

-Cells are specialised to carry out a specific function.


What is the organisation of a multicellular organism?

-Specialised cells.
-Organ system.
-Whole organism.


How are erythrocytes specialised?

-Red blood cells have flattened biconcave shape which increases SA:V, essential for transporting blood.
-No nuclei or organelles so increased space for haemoglobin.
-Flexible so can squeeze through narrow capillaries.


How are neutrophils specialised?

-White blood cells have multi-lobed nucleus which makes it easier to squeeze through small gaps to get to infection site.
-Granular cytoplasm contains lysosomes that contain enzyme to attack pathogens.


How are sperm cells specialised?

-Have tail or flagellum to help with movement.
-Contain mitochondria to supply energy to swim.
-Acrosome on head contain digestive enzymes to digest ovum.


How are palisade cells specialised?

-Chloroplasts for photosynthesis.
-Rectangular shaped so can be closely packed together.
-Thin cell walls which increase rate of CO2 diffusion.
-Large permanent vacuole to maintain turgor pressure


How are root hair cells specialised?

-Long extensions which increase SA which maximises uptake of water and minerals from soil.


How are guard cells specialised?

-Become less swollen when lose water so they close to prevent water loss.
-Cell wall is thicker on one side so doesn't change shape symmetrically when loses volume.


What is a tissue?

-Collection of differentiated cells.


What are the types of tissues?

-Nervous tissue; transmission of electrical impulses.
-Epithelial tissue; cover body surfaces.
-Muscle tissue; contract.
-Connective tissue; gold tissues together.
-Epidermis tissue; cover plant surfaces.
-Vascular tissue; transport water and nutrients.


How is squamous epithelium specialised?

-Very thin due to flat cells and only one cell thick.
-Rapid diffusion across a surface.


How is ciliated epithelium specialised?

-Cilia move in rhythmic manner.
-Goblet cells also present which release mucus, and cilia sweep away mucus.


How is cartilage specialised?

-Found in ear, nose, between bones.
-Prevents ends of bones from rubbing due to containing fibres of elastin and collagen.


How is muscle specialised?

-Skeletal muscle fibres contain myofibrils which contain contractile proteins.


How is the epidermis specialised?

-Single layer of closely packed cells.
-Covered by waxy cuticle to reduce water loss.
-Stomata present to let oxygen and carbon dioxide in and out.


How is the xylem tissue specialised?

-Transport of water and minerals
-Composed of elongated dead cells which are strengthened by lignin which provide structural support for plants.


How is the phloem tissue specialised?

-Transport of nutrients.
-Composed of sieve tube cells and separated by sieve plates.


What is an organ?

-Collection of tissues.
-E.g. heart or leaf.


What is an organ system?

-Composed of many organs working together to carry out a function.
-Digestive system and cardiovascular system.