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Biology 2017 > Organisms > Flashcards

Flashcards in Organisms Deck (125):
1

What do all organisms that reproduce sexually begin as

Fertilised eggs or zygotes

2

Are all cells in the body genetically identical?

Yes, excluding mutations

3

What happens in a cell as at begins to divide?

Certain genes are activated and others are inactivated, activated ones are activated to produce certain proteins

4

What is the hierarchy from smallest to largest

Cells, tissues, organs, organ systems and organisms

5

Define homeostasis

Organisms ability to maintain internal consistency and respond to environment change

6

We ... And .... To external stimuli

Detect and respond

7

Three example of receptors

Thermoreceptors, auditory receptors, photoreceptors

8

Define the pain threshold

The level at which the body has to respond to stimuli

9

What are nerves

They transmit information from the environment to the brain via nerve cells and back to muscle for a responses

10

What are hormones

Chemicals from endocrine glands travel around blood to bring out an effect or response in another tissue or organ

11

How do the nervous and endocrine system work together

They control and regular homeostasis

12

An example of how the endocrine and hormone system work together

If body temperature rises the nervous system causes the body to sweat and the heart rate to increase, whilst the hormonal system will caused decreased metabolism and vasoconstriction shut vessels

13

What are the two different types of hormones

Peptide and Steroid

14

Define peptides

Action occurs on the exterior of cells

15

Define steroids

Water soluble and hence passes through membrane to work on the inside of the target cell

16

Stimulus response model from left to right

Stimulus -> Receptor -> Coordinator -> Effector -> Response

17

Location of the stimulus

External / Internal

18

Location of the receptor

Cell / Organ

19

Location of the coordinator

Brain/ Spinal Chord

20

Location of effector

Muscle / Gland

21

Location of response

Movement / Secrete

22

What two systems make up the nervous systems

Central Nervous System & Peripheral Nervous System

23

Two aspects of the central nervous system

Brain and the spinal chord

24

What are the two aspects of the peripheral nervous system

Somatic (Sensory) N.S & Autonomic (motor/ movement)

25

What connects the somatic and autonomic N.S

Central Nervous System

26

Two aspects of the autonomic n.s

Sympathetic and Parasympathetic

27

What is the sympathetic nervous system

Fight / Flight

28

What is the parasympathetic nervous system

Rest / Digest

29

What is a sympathetic response

The body shuts down everything unnecessary and highlights what is needed

30

How does the nervous system react to increased body temperature

Sweat, Hair Flattens, Increased heart rate

31

How does the hormonal system contribute to decreased body temperature

- release

32

3 methods of material exchange

Diffusion / Osmosis, facilitated diffusion, Active Transport

33

Requirements of the exchange surface on the cell

High surface area, thin - one cell thick, moist - water soluble, warm - more kinetic energy

34

Two things lymph vessels do

Carry lymphocytes to the site of action
Drain excess fluid from tissue bed

35

What do the kidneys remove

Materials containing nitrogen eg urea

36

What is a nephron

The functional and structural unit of the kidney

37

Process of digestion

Glycerol -> epithelial cells -> lacteal

38

What happens to blood as it passes through the lungs

Gains fresh oxygen and loses carbon dioxide

39

What are the four limiting factors of photosynthesis

Temperature, light intensity, CO2 conc, colour

40

Autotrophs make ...

Organic compounds from inorganic compounds

41

Heterotrophs cannot ...

Make their own food from inorganic compounds

42

Catabolic reactions ...

Produce usable energy

43

Aerobic reaction with glucose formula

C6H12O6 + 6O2 -> 6H2O + 6CO2 + (35) ATP (40% efficient)

44

Lactic acid fermentation formula (anaerobic)

C6H12O6 -> 2C3H6O3 + (2) ATP

45

Alcohol fermentation (Anaerobic ) equation

C6H12O6 -> 2CO2 + 2C2H5OH + (2) ATP

46

Two forms of unicellular cell division

Mitosis and Binary fission

47

How do plants reproduce

Make clones through stems, roots, etc

48

Full steps of meiosis

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Cytokenesis & Prophase 2 AND Metaphase 2, Anaphase 2, Telophase 2

49

What causes variation in daughter cells after Meiosis

Chromosomes crossing

50

Mutation + Natural Selection =

Variation

51

Define Transgensis

Desirable genes transferred from one organism too another

52

Define Gene Therapy

Implanting helpful genes into a diseased organism to help fight diseases

53

Define Cloning

Make a replicate of the organism - don't confuse with gene cloning

54

Define vegetative propagation

Making clones of plants

55

Positives of vegetative propagation

Yield improvements, improve resistance, super foods, very cost efficient

56

Negatives of vegetative propagation

Unknown long term side effects, hard to regulate, may have ecological, less native species

57

Advantages of unicellular organisms

Easier to adapt to changes in the environment
Reproduce quickly
Large SA:V

58

Disadvantages of unicellular organism

Small
Don't live long
Usually need to live in water, must have food rich environment, must take in everything directly through the cell membrane

59

Advantages of multicellular organisms

Can live in wide variety of enviroments
Can grow very large
Long life
Work more efficiently

60

Disadvantages of multi cellular organisms

Need to 'eat' more
Grow for a long time before being born
If organ / system fails whole organism can fail
Small SA:V on the outside

61

3 types of epithelial tissue

Squamous, cuboidal, columnar

62

What does connective tissue do

Holds things together

63

Define Organs

Discrete structures made of several types of tissues that perform specific functions

64

Define systems

Group of organs that coordinate that carry out specific functions

65

Function of the epithelial tissue

Cover the body surfaces and line internal organs / cavities

66

Function of Connective tissue

Holds organs and other tissues together and fill spaces between

67

Function of adipose tissue

Adipose tissues are packed tightly together to ... Insulation, protective pads and for storage

68

Function of bone tissue

Solid matrix which gives organism structure

69

Tissues in the heart

Muscle, connective, nerve

70

Tissues in the lungs

Epithelial, connective, muscle

71

Tissues in the intestine

Epithelial, connective, muscle

72

Hormones are secreted by the endocrine glands ....

Directly into the blood where they act on target tissues or cells

73

What must target cells have in relation to hormones

Complementary receptors

74

Pathways in the nervous / endocrine system

N: Direct via axons / nerves
E: Indirect via blood

75

Messages in the nervous vs endocrine system

N: Electrochemical
E: Chemical

76

Site of action in the nervous vs endocrine system

N: higher specified
E: Target cells / tissues - can be everywhere

77

Speed in the nervous vs endocrine system

N: Fast
E: Slow

78

Duration in the nervous vs endocrine system

N: Short
E: Long

79

Transmission of message

PNS - Sensory Neuron
Inter Neuron
PNS - Motor Neuron

80

What are reflex responses

Act without the brain to keep organism away from danger / harm

81

5 examples of reflex responses

Pupils reflex, knee - jerk reaction, contraction of inner ear, swallowing food, keep away from heat source

82

What is negative feedback

When the response in the body reduces the effect of a stimulus

83

Example of negative stimulus

Increased light, response is to close pupil

84

What is positive feedback

When there is an increase in stimulus and an increase in response

85

Example of stimulus response model when body temp drops

Receptor : Hypothalamus
Effectors : skeletal Muscle
Response : contract and relax which produces heat

86

Example of stimulus response model when body temp increases

Receptor: Hypothalamus in brain looks at blood temperature
effectors: sweat glands secrete and layer body in sweat
response : heat is lost and body temp decreases

87

Three things that decrease body temperature

sweating, vasodilation and decreased thyroxine

88

Three Things that increase body temp

Shivering, vasoconstriction and increased thyroxine

89

How do nutrients enter the body

Via the digestive tract

90

What are proteins converted to in digestion

Amino acids

91

What are lipids converted to in digestion

Fatty acid and glycerol

92

What are carbohydrates converted to in digestion

Glucose

93

What are nucleic acids converted to in digestion

Nucleotides

94

Where is digested food absorbed into the bloodstream

The small intestine

95

What does the small intestine contain and what do they do

Villi and micro villi, increase surface area

96

How are the products of fat digestion absorbed into the central lacteal

Pinocytosis

97

How are additional nutrients absorbed into capillaries

Occurs in the villi through active transport and diffusion

98

What are metabolic wastes produced as a by product of

Cellular metabolism

99

What is the main metabolic waste in humans and how is it created

Urea, created when excess amino acids are converted to glucose in the liver

100

Where in the kidneys is blood filtered

Nephrons

101

What does the first stage of filtration involve

Filtration of materials from the blood at the glomerulus from the capillary into the bowmans capsule, caused by blood pressure

102

What occurs in Reabsorption in the kidneys

Materials move along the kidney tubule, materials needed are reabsorbed into blood steam by active transport, diffusion and osmosis

103

What two types of organs is the kidney

Excretory and osmoregulatory (regulates salt and water levels in the blood)

104

What does the circulatory system do

Connects exchange surfaces with body tissues

105

What happens as blood moves along the capillaries

There is an exchange of materials between the blood and tissue fluid surrounding the cells

106

Describe the structure of a nephron

Consists of a Bowmans capsule, containing a ball of capillaries called the glomerulus and a long tubule that drains into a collecting duct

107

Filtration in the kidneys occurs from the ... to the ...

Glomerulus -> Bowmans capsule

108

Réabsorption in the kidneys occurs from the ... to the ...

Tubule -> blood capillaires

109

During gas exchange oxygen goes from the ... to the ...

Alveolus -> Blood capillaries

110

During gas exchange carbon dioxide goes from the ... to the ...

Blood capillaries -> Alveolus

111

How do oxygen and carbon dioxide move across the alveolar membrane

Diffusion

112

3 things that effect rate of diffusion of the gases

Concentration gradient of the gases
Rate of blood flow
Raté and or depth of breathing

113

Formula for lactic acid

C3H6O3

114

What happens to lactic acid

It's converted to lactate which may be dissolved in blood and carried to the liver where it's converted to pyruvate and respired aerobically

115

Which produces more energy aerobic or anaerobic respiration

Aérobic produces 36-38 ATP while anaerobic produces 2

116

Four main areas that require provision of energy

Growth
Movement
Repair
Reproduction

117

What is budding

Form of asexual reproduction in plants where buds are produced that break away and begin to grow as a new organism

118

What is fragmentation

Form of asexual reproduction in animals where the adult body breaks into several pieces and each is able to grow into another individual

119

What is vegetative propagation

A sexual reproduction in plants where part of adult body is broken off and grows into a seperate self supporting plant body

120

What does it mean when cells differentiate

As organisms grow cells differentiate so that in different cells different genes will be expressed and the cells will have different structures and perform different functions within the organism

121

What does the thyroid gland produce and what does this do

Thyroxine, stimulates metabolism and heat production

122

What does the adrenal gland produce and what does this do

Adrenaline, increases blood and constricts blood vessels

123

Stimulus response model book

Stimulus -> Receptor -> Transmission -> Effector -> Response -> negative feedback

124

Corrective mechanisms when there is an increase in body temperature

Sweating, hair lies flat, blood to surface,decrease in metabolic rate

125

Corrective mechanisms when there's a decrease in body temperature

No sweating, hair raised, blood kept away from surface, increase in metabolic rate, shivering