3rd Form Definition and Key Concepts Flashcards
1
Q
cell
A
the basic building block of all living organisms that are made up of organelles
2
Q
eukaryotic cell
A
a type of cell found in animal, plant, fungi and protoctist cells that contain a nucleus
3
Q
animals
A
a kingdom where all organisms are multicellular, do not photosynthesize, no cell walls and store their carbohydrates as glycogen
4
Q
plants
A
multicellular, cells do contain chloroplasts, do photosynthesize, do contain cell walls and store carbohydrates as starch
5
Q
fungi
A
no photosynthesis, feed via saprotrophic nutrition, composed of mycelium which consists of many hyphae, can be both multi and unicellular (yeast), contain cell walls and store carbohydrates as glycogen
6
Q
protoctists
A
microscopic, single celled organisms
7
Q
prokaryotic cell
A
a cell found in the bacteria kingdom that does not contain a nucleus
8
Q
bacteria
A
single celled, prokaryotic (no nucleus) organisms, contain a cell wall and plasmids
9
Q
virus
A
a non-living organism that can only reproduce inside host cells (parasitic). they
have no cells and contain a protein coat and nucleic acids (DNA or RNA)
10
Q
unicellular
A
an organism made up of a single cell (bacteria and protoctista)
11
Q
amoeba
A
protoctists that live in pond water and resemble animal cells with
chloroplasts
12
Q
chlorella
A
a protoctist that has features similar to plant cells, e.g. chloroplasts
13
Q
chloroplast
A
an organelle that is the site of photosynthesis
14
Q
DNA
A
a double stranded molecule made of nucleotides, wound in a double helix shape, carrying the genetic code
15
Q
human immunodeficiency virus (HIV)
A
a virus that weakens the immune system and can lead to acquired immunodeficiency syndrome (AIDS)
16
Q
influenza
A
an infectious virus that causes the flu
17
Q
hyphae
A
long filaments of a fungus that contain many nuclei
18
Q
lactobacillus bulgaricus
A
a rod-shaped bacteria, used to produce yoghurt from milk
19
Q
MRS H GREN
A
the characteristics an organism must have to be classed as living;
Movement, Respiration, Sensitivity (to their environment), Homeostasis, Growth,
Reproduction, Excretion and Nutrition
20
Q
mucor
A
a multicellular fungus that has many hyphae
21
Q
multicellular
A
refers to an organism that is made up of more than one cell. these
organisms are only found in animals, plants and some fungi
22
Q
mycelium
A
a collection of thread-like hyphae in fungus
23
Q
pathogens
A
microorganisms that cause disease to its host that can include bacteria,
protoctists, fungi and viruses
24
Q
photosynthesis
A
a reaction where energy is transferred from the environment to the chloroplasts by light to produce glucose
25
plasmids
loops of DNA found in the cytoplasm of prokaryotic cells
26
plasmodium
pathogenic protoctists that cause malaria
27
pneumococcus
a spherical, pathogenic bacteria that causes pneumonia
28
saprotrophic nutrition
the mode of extracellular nutrition in which digestive enzymes are secreted onto food outside of the cell and the products of digestion are absorbed
29
yeast
a single celled fungus
30
tobacco mosaic virus (TMV)
a plant pathogen which produces a mosaic pattern on the leaves, infecting chloroplasts and limits plant growth
31
organelle
a specialised structure found inside of cells, e.g. a nucleus
32
cell
the basic building blocks of all living organisms
33
tissue
a collection of cells with similar structure and function
34
organs
collection of tissues performing specific functions
35
organ system
group of organs that work together to form organisms
36
cell differentiation
the process where cells become specialised by producing
different proteins
37
cell membrane
a partially permeable barrier that surrounds the cell (allows some
substances to move in and out of the cell)
38
cell wall
a fully permeable outer layer found in some cells. In plants it is made from cellulose and in fungi, chitin
39
chloroplast
an organelle that is the site of photosynthesis
40
cytoplasm
contains dissolved nutrients and all of the organelles of the cell and the
site of many metabolic reactions
41
mitochondria
an organelle that is the site of aerobic respiration
42
nucleus
an organelle found only in eukaryotic cells and contains the genetic material (DNA) and controls the activities of the cell
43
ribosomes
organelles that are the site of protein synthesis
44
stem cells
undifferentiated cell that can divide rapidly to produce specialised cells
45
vacuole
found in plant cells, contains dissolved nutrients and supports the shape of the cell
46
lipids
a group of molecules including fats and oils, made from fatty acid chains and glycerol containing the elements carbon, hydrogen and oxygen. can test for them
using the emulsion test
47
proteins
large polymers made from amino acids, containing the elements carbon, hydrogen, oxygen, nitrogen and occasionally other elements like sulphur, involved in
repairing and the growth of cells. can test for them using the biuret test
48
amino acids
the monomer from which proteins are assembled from
49
starch
a carbohydrate made from glucose monomers, containing the elements carbon, oxygen and hydrogen and acts as an energy store in plants. can test for starch
using iodine
50
glycogen
a carbohydrate made from glucose that acts as an energy store in animals
51
enzymes
proteins that are biological catalysts that increase the rate of reactions by providing an alternative pathway with a lower activation energy
52
active site
part of the enzyme that is complementary to the shape of the substrate which can change shape if the enzyme is exposed to extreme pH solutions or high
temperatures. this would result in less enzyme-substrate complexes
53
diffusion
the net movement of substances from an area of high to low
concentration, down a concentration gradient and can be across a partially permeable
membrane
54
concentration gradient
the difference in concentration between two areas
55
surface area to volume ratio (SA:V)
the size of the object compared with the area that is in contact with the environment
56
oseophagus
a muscular tube that takes food from the mouth to the stomach
57
alimetary canal
the digestive tract running from the mouth to the anus
58
peristalsis
the contraction and relaxation of muscles all along the alimentary canal that pushes the food along
59
amylase
an enzyme produced in the salivary glands and pancreas that speeds up the breakdown of starch into maltose
60
duodenum
the first part of the small intestine where food is broken down by the
pancreatic juices; lipids --> fatty acids + glycerol by lipases, proteins --> peptides/amino acids by proteases such as trypsin and carbohydrates like starch, that
get broken down into maltose by amylase
61
ileum
second part of the small intestine where the products of digestion are
absorbed, adapted with one cell thick wall (short diffusion distance), high surface area
(villi and microvilli) and high concentration gradient (capillaries)
62
bile
made in the liver, stored in the gall bladder and works in the duodenum where it emulsifies lipids and with pancreatic juices, neutralises stomach acid
63
colon
first part of the large intestine where water is reabsorbed
64
lipase
an group of enzymes produced in the pancreas that speeds up the
breakdown of lipids into fatty acids and glycerol
65
maltase
an enzyme produced in the small intestine that speeds up the breakdown of maltose into glucose
66
pancreas
an organ that produces and secretes enzymes such as amylase, lipases and proteases that make up the pancreatic juices and releases them into the duodenum
67
rectum
last part of the large intestine, where faeces are stored
68
stomach
food enters here after travelling down the oesophagus. stomach acid makes conditions acidic, perfect for pepsin which works here as it has an optimum pH
of 2. the acid kills any pathogens on the food. muscular walls contract to move food around and increase the chance of food coming into contact with enzymes
69
surface area
the total area occupied by the surface of an object, leaves have a large surface area to absorb maximum sunlight
70
villi
small, finger like projections on the surface of the ileum that increase surface area for maximum absorption. the walls of the villi are folded themselves (microvilli)
to increase surface area further
71
proteases
a group of enzymes that speed up the breakdown of proteins into
peptides/amino acids. an example being pepsin in the stomach with an optimum pH of 2 and other proteases get released into the small intestine from the pancreas
72
photosynthesis
an endothermic reaction where energy is transferred from the
environment to the chloroplasts by light from the sun. glucose is made.
73
glucose
made during photosynthesis. can be stored as starch, used straight away in respiration or used to make cellulose.
74
spongy mesophyll
a tissue found in plant leaves that is specialised for gas exchange
by having air spaces that allow the diffusion of gases to happen quicker
75
stomata
small holes found in the lower epidermis that open and close thanks to the guard cells. control the loss of water by closing during the night but open during the
day thanks to the guard cells to allow the diffusion of carbon dioxide and oxygen
76
waxy cuticle
on top of the upper epidermis that is insoluble so waterproofs the leaf
and reduces the evaporation of water but transparent to allow light to pass through
77
palisade mesophyll
a tissue found in plant leaves that are specialised to carry out
photosynthesis by being vertically packed to capture more sunlight and to store more chloroplasts
78
aerobic respiration
respiration that uses oxygen to release lots of energy from
breaking down glucose. the word equation:
glucose + oxygen --> carbon dioxide + water
the chemical equation:
C6H12O6 + 6O2 --> 6CO2 + 6H2O
79
anaerobic respiration
respiration without oxygen, that releases less energy than
aerobic respiration, represented by the word equation:
glucose --> lactic acid
80
ATP
adenosine triphosphate, a molecule made up of adenine (nitrogenous base, ribose (sugar) and three phosphates. releases energy quickly
81
cellular respiration
an exothermic reaction that continuously occurs in cells and
releases energy from nutrients
82
alveoli
tiny air sacs in the lungs at the end of the bronchioles where gas exchange occurs. adapted for gas exchange by having thin, moist walls for a short diffusion
distance, folded walls for a larger surface area and capillaries close by to maintain a high concentration gradient
83
bronchi
airways branching from the trachea that lead into the lungs
84
bronchioles
small airways branching from each bronchi in each lung
85
capillaries
thin, narrow blood vessels where the exchange of substances between the blood and tissues occurs, for example o2, glucose, co2
86
diaphragm
muscle that contracts and relaxes to change the volume of the thorax
and ultimately the pressure to control inhalation and exhalation
87
intercostal muscles
muscles between the ribs that contract and relax to move the
ribcage and change the volume and pressure during inhalation and exhalation
88
pleural membranes
airtight membranes covering the lungs and the thorax to
maintain pressure changes and stop the lungs from sticking to the ribcage
89
trachea
windpipe connecting the lungs to the mouth and nose. contains lots of cartilage to ensure it stays upright and does not collapse inwards with the pressure
changes
90
aorta
the main artery that takes oxygenated blood away from the heart, specifically the left ventricle, to the rest of the body
91
artery
type of blood vessel that carries blood under high pressure, away from the heart to the tissues of the body. most arteries carry oxygenated blood apart from the pulmonary artery. arteries have a narrow lumen, thick elastic, muscular and outer layers
92
atria
the two chambers at the top of the heart that receive blood from the veins and pump blood to the ventricles. much thinner walls compared to the ventricles
due to the distance the blood has to travel and therefore the blood does not need a high pressure
93
blood
a tissue contains red blood cells (which carry oxygen), white blood cells (phagocytes and lymphocytes), platelets (involved in clotting) and plasma (carries carbon dioxide, glucose and amino acids)
94
lymphocyte
a type of white blood cell that produces antibodies that are specific to a pathogen
95
phagocyte
a type of white blood cell that engulfs pathogens
96
plasma
the liquid component of blood that transports waste products like carbon dioxide, urea and heat and useful products like hormones, dissolved nutrients like
glucose and amino acids and antibodies
97
platelets
fragments of cells found in blood that are involved in clotting as when exposed to the air it causes the soluble fibrinogen to change to insoluble fibrin which acts as a net, collecting RBCs, forming a clot
98
red blood cells
cells found in blood that contains haemoglobin that transports
oxygen. they have a biconcave shape to increase surface area so more oxygen can be absorbed, no nucleus and contain haemoglobin so more oxygen can be carried
99
coronary heart disease (CHD)
a disease caused by the build-up of fatty deposits inside the coronary arteries (arteries supplying blood to the heart), causing them to
narrow and reduce blood flow to the heart, resulting in less oxygen and glucose to the heart, reducing aerobic and increasing anaerobic respiration, eventually
resulting in a heart attack
100
haemoglobin
red protein found in red blood cells that is responsible for transporting oxygen
101
heart
the organ the pumps blood around the body in the closed, double
circulatory system in humans
102
veins
a blood vessel that carries blood at low pressure back to the heart, often deoxygenated apart from the pulmonary vein. contains a wider lumen, thinner elastic, muscular and outer layers and valves
103
hepatic artery
artery that supplies the liver with oxygenated blood
104
hepatic portal vein
carries blood from the intestines to the liver, high in glucose
105
hepatic vein
vein that carries blood away from the liver back to the heart
106
pulmonary artery
the artery that takes deoxygenated blood from the heart, specifically the right ventricle to the lungs
107
pulmonary vein
the vein that carries oxygenated blood from the lungs to the
heart, specifically the left atrium
108
renal arteries
the arteries that supply blood to the kidneys
109
renal veins
veins that take blood away from the kidneys
110
vena cava
the vein that takes deoxygenated blood back to the heart, specifically
the right atrium, from the body
111
ventricles
the lower chambers of the heart that receive blood from the atria and pump blood out of the heart into the arteries at high pressure
112
white blood cell
cells of the immune system that protects the body from pathogens by producing antibodies or engulfing them
113
root hair cells
specialised cells that are responsible for the absorption of water and mineral ions from the soil by having a large surface area for maximal absorption and lots of mitochondria form the active transport of mineral ions
