specialized cells

Question 1

Differentiation

Answer 1

• the process by witch stem cells become specialized for a particular function
  After 16 cell structure cells can:
• change shape
• change type or number of oraganells within
• switch off geans that arn’t needed so only protines needed are produced

Question 2

during differentiation a cell may:

Answer 2

• change shape
• change type of number of organelles within
• switch off genes so that it only produces the proteins that it needs

Question 3

Red Blood Cells

Answer 3

• biconcave and flexible shape
  > increases surface area of cell surface membrane
  > increases rate of gas diffusion (short diffusion distance)
  > increases the flexibility of the cell to squeeze through narrow capillaries
• small diameter to travel through tiny capillaries
• no membrane bound organells
• contains hemoglobin (carries oxygen)
• transports some carbon dioxide from respiring cells to lungs

Question 4

WBC: Neutrophils

Answer 4

• multi-lobed nucleus makes cell flexible
• can squeeze out of small pores in capillary walls to get to infection sight
• contains lysosomes
• most common type of WBC
  Phagocytic:
• engulfs and destroys pathogens

Question 5

WBC- Lymphocytes

Answer 5

• B lymphocytes and T lymphocytes
• B cells produce antibodies that bind to complementary antigens
• T cells signal to B cells
  immunological memory
• Some T cells can destroy cancer cells or infected host cells
• large neuculus

Question 6

Sperm Cell

Answer 6

• mid section contains lots of mitochondria for aerobic respiration
• head contains nucleus and acrosome
  > acrasome contains digestive enzymes to digest zona pellucida so sperm can enter egg cell

Specialisation:
- acrosome
- mid section
- flagellum

Question 7

What are tissues?

Answer 7

• a collection of similar specilised cells preforming a spesific function

Question 8

What is an organ?

Answer 8

• a collection of tissues preforming spesific physiological funtions

Question 9

Root hair cell

Answer 9

• cover plant roots to increse sureface area
• absorbe water via osmosis
• cell membrain partally permiable to water
• mitochondria procides energy (ATP) for active transport
• thin celulose cell wall for short diffusion distance
• large vacuol to draw water in (somosis)