Unit 2- Multicellular Organisms Flashcards
1
Q
What is a organ?
A
An organ is a structure composed of several different tissues coordinates to perform one or more functions.
2
Q
What is a system?
A
A group of related tissues and organs make up a system.
3
Q
What is the function of a cheek epithelium?
A
Protection of mouth lining.
4
Q
What are the two types of blood cells?
A
Red blood cell.
White blood cell.
5
Q
What is the function of a red blood cell?
A
Uptake and transport of oxygen to living cells.
6
Q
What is the function of white blood cells?
A
Destruction of invading microbes.
7
Q
What is the function of a nerve (motor neuron)?
A
Transmission of nerve impulses.
8
Q
What is the function of xylem?
A
Support and water transport up the plant.
9
Q
What is the function of a stomach?
A
Churning and partial digestion of food.
10
Q
What is the function of the heart?
A
Pumping of blood.
11
Q
What is the function of a kidney?
A
Maintenance of water balance and removal of soluble wastes.
12
Q
What is the function of a lung?
A
Exchange or respiratory gases.
13
Q
Function of the skin?
A
Protection, temperature regulation and sensitivity.
14
Q
What are stem cells?
A
Stem cells are unspecialised animal cells involved in growth and repair.
15
Q
What are stem cells able to do?
A
- reproduce themselves indefinitely by repeated mitosis.
- develop into various types of specialised cell when required, to replace cells that have come to the end of their life or have been damaged or lost.
16
Q
What takes place at meristems?
A
Production of new cells.
17
Q
Where are meristems found?
A
Tips of shoots and at the tips of roots.
18
Q
What do meristematic cells have the potential to do?
A
Meristematic cells have the potential to become any type of plant cell.
19
Q
What are the three parts composed to make a nervous system?
A
The brain, spinal cord and the nerves.
20
Q
What do the brain and the spinal cord make up?
A
The central nerves system.
21
Q
What are the regions of the brain?
A
Medulla, cerebellum and the cerebrum
22
Q
What does the medulla control?
A
The rate of breathing and heart rate.
23
Q
What does the cerebellum control?
A
Balance and muscular coordination.
24
Q
What does the cerebrum control?
A
Mental processes such as memory, reasoning, imagination, conscious thought and intelligence.
25
What is the largest part of the brain?
CEREBRUM
26
The nervous system is made up of nerve cells called?
Neurons.
27
How is an electrical impulse carried towards the cell body of a neuron?
A sensory fibre and away from of by a axon fibre.
28
What are the 3 types of neurons?
Sensory
Relay
Motor
29
What is a reflex action?
Is a rapid,automatic, involuntary response to a stimulus.
30
What do reflex actions prevent?
The body from damage. Since they do not need conscious thought by the brain, many reflex actions may still be performed for a short period by animal whose brain has been destroyed.
31
What are hormones?
Hormones are chemical messengers secreted directly into the bloodstream by endocrine.
32
What do hormones stimulate?
Specific target tissues.
33
What is a tissue?
A tissue is a group of cells specialised to perform a particular function.
34
What are people with diabetes unable to control?
Their blood glucose levels
35
What is the cause of type 1 diabetes?
Genetics, environmental factors, autoimmune factors.
36
How is type 2 diabetes caused?
Unhealthy diet leading to obesity, physical inactivity and genetics.
37
What is the treatment for diabetes?
Treatment for those who fail to produce insulin takes the forms of regular injections of insulin and careful diet. Treatment for those people whose target tissues fail to respond to insulin takes form of excersise, weight lose, diet control and additional insulin in some cases.
38
What happens if diabetes is left untreated?
Rape increase in blood glucose concentration occurring after every meal. Kidney disease and a form of eye condition that can result in blindness.
39
What could happen if there is a presence of to much or to little glucose?
Could lead to osmotic imbalances.
For example, it could result in the cells gaining too much water from, or losing too much water to, the surrounding intercellular fluid by osmosis.
40
Normal body cells are?
Diploid
41
Sex cells (gametes) are?
Haploid
42
What is reproduction?
reproduction is the process by which the members of a species produce offspring.
43
What does sexual reproduction involve?
The fusion of two gametes during fertilisation.
44
What is the site of sperm production?
Testes
45
What is the site of the egg?
Ovaries
46
Which is produced more sperm or egg?
Sperm is seen to be produced over 250,000,000 times a male ejaculates.
47
What is fertilisation?
This process involves a haploid sperm reaching a haploid end and then the sperms nucleus entering the egg and fusion with the eggs nucleus to form a singe diploid cell called a zygote.
48
What does a zygote contain?
Genetic information from both parents and it it the first cell of a new individual.
49
What is the anther?
The make sex organs of the flower
50
What is the ovules?
The plants female sex cells, and are produced in the ovary, the female sex organ of the flower.
51
What is pollination?
Pollination is the transfer of pollen grains from an anther to a stigma. It should not be confused with fertilisation.
52
What is the growth of a pollen tube?
Once a pollen grain had landed on a stigma, it responds to the presence of sugar on the stigma and uses the sugar as an energy source to form a pollen tube.
53
What is fertilisation in plants?
The tip of the pollen tube bursts and the two haploid male gametes enter the sac. One fuses with the haploid egg cell to form a diploid zygote.
54
What are the two types of variation?
Discrete variation and continuous variation
55
What is a discrete variation?
If it can be used to divide up the members of a species into two or more distinct groups.
Example - ability or inability to roll their tongue.
Blood types- A,B, AB, O
56
What is continuous variation?
When it varies amongst the members of a species in a smooth, continuous way from one extreme to the other and does not fall into distinct groups.
For example- seed length in broad beans varies continuously and height in humans vary continuously.
57
Examples of discrete variation?
```
Ear lobe types in humans
Fingerprint types in humans
Hair type in humans
Eye colour in fruit flies
Wing length in fruit flies
Coat colour in Guinea pigs
```
58
Examples of continuous variation?
```
Body mass in humans
Hand span in humans
Foot length in humans
Resting heart rate in humans
Length of index fingers in humans
```
59
How do you normally present discrete variation?
In a form of a bar graph.
60
What is the significance of sexual reproduction?
Each new member of a species formed by sexual reproduction receives half of its genetic material from one parent and half from the other parent.
61
What is a phenotype?
Physical characteristics that organisms have is said to be their phenotype.
62
What is a genotype?
The complete set of genes possessed by an organism is called its genotype.
63
What are alleles?
Different forms of genes.
64
How many alleles for one gene?
2
65
How many alleles for each gene does a gamete have?
1
66
What are symbols?
For convenience, the dominant and recessive alleles of a gene are often represented by symbols.
67
What is homozygous?
When an organism possesses two identical alleles of a gene it's genotype is said to be homozygous and it is true-breeding.
68
What is heterozygous?
When an organism has two DIFFERENT alleles of a gene it's genotype is said to be heterozygous and is NOT true-breeding.
69
What is polygenic inheritance?
A characteristic showing continuous variation is controlled by the alleles of more than one gene and is said to show polygenic inheritance.
70
Polygenic inheritance in humans
Many human characteristics such as height; weight, skin colour, hand span and foot size shoe a pattern of polygenic inheritance.
71
Environment?
Many characteristics that show continuous variation are influenced by the environment.
72
What is a family tree used for?
Laws of genetics still apply to humans and particular traits can be traced through several generations of a family by constructing a family tree.
73
What is the use of family trees?
A family tree may be constructed and used by genetic counsellor when advice is needed by a couple concerned about passing on genetic disorder to their children.
74
Examples of dominant and recessive?
In humans, the allele for red hair (h) is recessive to the dominant allele for non-red hair (H).
75
What is cystic fibrosis?
Cystic fibrosis is a genetic disorder caused by a change (mutation) to one gene. It results in the sufferer producing mucus that is thicker and stickier than normal. This causes congestion of the lungs and other organs.
76
What are the names of the 4 chambers?
Left atrium
Left ventricle
Right atrium
Right ventricle
77
What does the circulatory system consist of?
The heart and the blood vessels, which Carr blood to all parts of the body. Nutrients, oxygen, carbon dioxide and hormones are transported in the blood.
78
How does blood enter the right atrium?
By the main vein called the vena cava.
79
How does the blood flow happen?
Blood from the body enters the right atrium by the main vein vena cava. The right atrium contracts, pumping blood into the right ventricle. Contraction of the muscular ventricle wall forces blood into the pulmonary artery. This vessel carries blood from the heart to the lungs where it takes up oxygen.
The pulmonary vein returns oxygenated blood from the lungs to the hearts left atrium. The blood is then pumped into the left ventricle where strong contraction of the muscular wall forces blood into the main artery called the aorta. The aorta takes blood to all parts of the body. These tissues and organs remove the oxygen as the blood passes through, making it become deoxygenated.
80
Which ventricle wall is thick?
The wall in the left ventricle is particularly thick and muscular since it's required to pump blood all around the body. The wall of the right ventricle is less thick since it only pumps blood to the lungs.
81
On a diagram of a heart what does the colours blue and red represent?
Red- oxygenated blood
| Blue- deoxygenated blood
82
What is an artery?
An artery is a vessel that carries blood away from the heart. It has a thick muscular wall that is able to withstand the high pressure of oxygenated blood coming from the heart.
83
What is the exceptional artery that carries deoxygenated blood?
Pulmonary artery.
84
What are capillaries?
Capillaries are the most numerous type of blood vessel in the body. They present a large surface area and are in close contact with the living cells in tissues and organs.
85
What are capillaries often referred to?
Exchange vessels, since all exchange of materials between blood and living tissues take place through their thin walls.
86
The first branch of the main artery leaving the heart is called the?
Coronary artery.
87
What is the function of a coronary artery?
This artery supplies the muscular wall of the heart itself with oxygenated blood.
88
What is the red pigment in red blood cells called?
Haemoglobin.
89
Haemoglobin passes through lung capillaries and combines with oxygen to form?
Oxyhaemoglobin.
90
Surface area to volume ratios in transport systems in plants?
A small organism has a late surface area in relation to its volume, a large organism had a smaller surface area in relation to its volume.
91
What passive process is adequate to transport materials to all parts of the cell?
Diffusion.
92
Water enters root hair by?
Osmosis
93
What do mesophyll cells need in the leaf?
Water for photosynthesis
94
What is transpiration?
Transpiration is the process by which water is lost by evaporation from the aerial parts of the plants. Most transpiration occurs through tiny pores in the leaves called stomata.
95
What is a stoma?
One of the many pores on lower lead surface in which carbon dioxide can dissolve before diffusing into green cells.
96
What are guard cells?
Pairs of cells which change shape and control gas exchange by closing stomata in darkness or when too much water is being lost.
97
How many layers does a leaf consist of?
4
98
What does phloem transport?
Sugar
99
What is special about the upper epidermis?
It is transparent to let the light through.
100
Is xylem living or non-living?
NON-LIVING
101
Is phloem living or non-living?
LIVING
102
What are phloem a composed of?
Sieve tubes and companion cells.
103
What are the lungs?
Mammals organs of gaseous exchange
104
Which tubes does air pass through?
The trachea, bronchi and bronchioles.
105
The larger airways are supported and held open by rings of?
Cartilage
106
The trachea and bronchi are lined with tiny hair like?
Cilia and cells that secrete sticky mucus.
107
What does the cilia do?
Sweeps mucus containing trapped dirt and micro-organisms upwards and away from the lungs.
108
Air passing along the narrow bronchioles ends up in tiny air sacs deep in the lungs called?
Alveoli
109
What can the alveoli do?
Provide a very large surface area for gas exchange.
110
Each alveolus is surrounded by a dence network of?
Blood capillaries
111
The lining of an alveolus is very?
Thin and in close proximity to the walls of the blood capillaries, which are themselves only one cell thick.
112
Blood arriving in a lung is described as?
De-oxygenated, because it contains a low concentration of oxygen.
113
Since air breathed into alveolus contains a higher concentration of oxygen, ______ occurs.
Diffusion occurs
114
What is the alimentary canal?
The body's digestive system
115
What is the oesophagus?
A muscular tube that connects the back of the mouth with the stomach.
116
Once food has bee swallowed, it is moved down the oesophagus by a form of muscular activity called?
Peristalsis
