Animal and plant cell biology Flashcards
(31 cards)
what is a platelet?
small fragments of cells which help blood clot at the side of a wound
What is a red blood cell?
cells which are packed with a red pigment called haemoglobin which binds the oxygen in the lungs to transport it around the body. There is no nucleus to provide more room for haemoglobin.
what is a white blood cell?
these cells form part of the bodies defence system against microorganisms two main types of phagocytes which engulf microbes and lymphocytes which make antibodies and antitoxins
what is plasma?
this liquid transports proteins, e.g. hormones, carbon dioxide from the organs to the lungs, soluble products of digestion from the small intestine to other organs and urea from the liver to kidneys
What does the diaphragm do?
Sheet of muscle which contracts to change the air pressure within the thorax to inflate/ deflate the lungs
What does the alveoli do?
Gas exchange of oxygen and carbon dioxide during breathing
what do the intercostal muscles do?
Increases the volume of the thorax
How is the alveoli adapted to its function?
Ventilation removes air
Spherical shape to give large surface area
Good blood supply maintains concentration gradient
What are the different parts of the heart?
Vena cava
Pulmonary artery
Pulmonary vein
Aorta
Left Ventricle
Left atrium
Right ventricle
Right atrium
Heart valves
What are the parts of the fish gills
Gill rakers
gill filaments
gill bar
gill arch
what are the adaptations of fish gills
Large surface area
Thin filaments
Good blood supply
What is epidermis
They cover the surface and protect them, often secreting a waxy substance that waterproofs the leaf
What is a palisade mesophyll
Contains lots of chloroplasts which carry out photosynthesis
What is the spongy mesophyll
Contains chloroplasts for photosynthesis but also has big air spaces and a large surface area for gas diffusion
What is a xylem
Carry water and dissolved minerals from the roots to leaves
What is the phloem
Carry dissolved food from leaves around the plant
Name 2 plant organs
Leaf
Stem
What are adaptations of root hair cells?
Thin cell extension- increases surface area and is thin so there is a short distance for osmosis of water and mineral ions
Lots of mitochondria- provides energy from respiration to drive active uptake of ions
What are the features of xylems
Elongated cells
Continuous tube because of no cell wall
Cellulose cell walls strengthened by lignin
Dead cells
Transports water and mineral ions
From roots to leaves
What are the features of phloems
Elongated cells
End cell wall called sieve plate
Regular cellulose cell walls
Living cell so the movement up and down can be controlled
Dissolves sugars
From leaves up and down the rest of the plant
What is the name of the movement which occurs in xylem and phloems
Translocation
What is the function of stomata and what are they?
They are small openings in the guard cell which open and close based on the CO2 and water vapour levels within the plant
Where are stomata positioned and why?
On the under side of the leaf so they are protected from direct sunlight which would evaporate the water
What is the process by which water is absorbed by plant roots and eventually released as vapor through stomata?
Transpiration
