Cell Organisation

Question 1

Guard Cells:

Answer 1

A pair of guard cells around a stoma, grow turgid and flaccid to control gaseous exchange in plant.

Question 2

What are organs:

Answer 2

Organs are a collection tissues working together for a specific function.

Question 3

What are tissues?

Answer 3

Tissues are collections of cells grouped for a specific function.

Question 4

What are organ systems?

Answer 4

Collection of Organs coordinated to fulfil a major specific function.

Question 5

How are Erythrocytes adapted to their function

Answer 5

• They have a flattened biconcave shape to increase their surface area : volume
• Have no nuclei to maximise storage of haemoglobin to carry more oxygen
• Flexible so they can fit in small capillaries

Question 6

How are Neutrophils adapted to their function

Answer 6

• Multi-lobed nucleus makes it easier to squeeze in small gaps e.g fenestrated capillaries
• Granular cytoplasm contains lysosomes to break down pathogens.

Question 7

How are sperm cells adapted to their function

Answer 7

• Have a flagellum for movement
• lots of mitochondria to provide energy for swimming
• Acrosome head contains digestive enzymes to break down protective layers around the ovum.

Question 8

How are Palisade cells adapted to their function

Answer 8

• Thin cell walls to maximise diffusion
• Large Vacuole to maintain turgor pressure
• Use cytoplasmic streaming to transport chloroplasts towards light.

Question 9

What are the 4 main categories of tissues in animals?

Answer 9

Nervous tissue - transmit electrical impulses
Epithelial tissue - cover internal and external body surfaces
Muscle tissue - adapted to contract
Connective tissue - hold tissues together

Question 10

How is Squamous epithelium tissue adapted to its function

Answer 10

Made up of squamous epithelium cells
Flat cells and 1 cell thick
Rapid diffusion across tissue
Lining of alveoli allowing for rapid diffusion of oxygen into blood.

Question 11

How is Ciliated epithelium tissue adapted to its function

Answer 11

Contains ciliated epithelial cells which have cilia.
Cilia rhythmically waft mucus away from lungs.
Goblet cells release mucus to trap unwanted particles present .

Question 12

How is cartilage tissue adapted to its function

Answer 12

-Contains fibres of elastin and collagen
Made up of chondrocyte cells
Firm and flexible connective tissue prevents bones waring away at eachother.

Question 13

How is muscle tissue adapted to its function

Answer 13

Contains skeletal muscle fibres which contain myofibrils which contain contractile proteins.

Question 14

How is epidermis tissue adapted to its function

Answer 14

• Closely packed cells to prevent unwanted entry and exit of particulates.
• Covered in a waterproof waxy cuticle to reduce the loss of water.
• Stomata formed by guard cells can open and close for gas exchange.

Question 15

How is Xylem tissue adapted to its function

Answer 15

• Responsible for transport of water and minerals.

- Composed of tracheary element strengthened by lignin for structural support.

Question 16

How is Phloem tissue adapted to its function

Answer 16

Composed of sieve tubes separated by perforated walls (sieve plates).
Sieve plates help transport sucrose up phloem