Chapter 07 - Living Tissues Flashcards
(123 cards)
1
Q
What is a tissue?
A
A group of cells with a common origin that has been modified to perform particular functions in the body
2
Q
What are the tissues in plants that divide actively by mitosis to produce new cells called?
A
Meristematic tissues
3
Q
What is the primary result of the activity of meristematic tissues in plants?
A
The growth of plants
4
Q
List three key features of meristematic tissues.
A
- This tissue consists of small sized living cells.
- No intercellular spaces or intercellular spaces are not prominent
- There is a distinct nucleus in each cell.
- (Other possible answers from the text: Absence of large central vacuole but small vacuoles may be present; Absence of chloroplasts; Large number of mitochondria are present)
5
Q
Where are apical meristems typically found in a plant?
A
Shoot apex, root apex, and axillary buds
6
Q
What is the main effect of the activity of apical meristems on a plant?
A
It increases the plant’s height.
7
Q
Where are intercalary meristems located in a plant?
A
At nodes
8
Q
What type of growth is associated with the activity of intercalary meristems?
A
Increase in the length of internodes (due to the activity of the above tissue).
9
Q
In what group of plants are intercalary meristems commonly found?
A
Plants of the grass family
10
Q
Where are lateral meristems located in a plant?
A
Laterally in the stem and roots of the plant.
11
Q
What is the primary effect of the activity of lateral meristems on a plant?
A
It increases the diameter (girth) of the plant.
12
Q
What is an example of a lateral meristem found in dicots that contributes to the increase in diameter?
A
Cambium tissue
13
Q
What is the type of permanent tissues that are a collection of one type of cells?
A
Simple permanent tissue
14
Q
What is the type of permanent tissues that are a collection of different types of cells
A
Complex permanent tissues
15
Q
What is the most abundant simple permanent tissue in plants?
A
Parenchyma tissue
16
Q
What are the features of a parenchyma tissue?
A
- Parenchyma tissue consists
of living cells. - Cells are isodiametric
(spherical) with a large
central vacuole. - Nucleus is present
peripherally in the cytoplasm. - The cell wall is thin and made
up of cellulose. - Intercellular spaces are
present.
17
Q
What are the locations of parenchyma tissues?
A
- Cortex and pith of plant stem
- Pith and cortex of roots
- Fleshy parts of fruits
- Seeds (endosperm)
- Leaves (mesophylls)
18
Q
What is a major function of parenchyma tissue in plant leaves related to chloroplasts?
A
Photosynthesis (Palisade and spongy mesophyll contain chlorophyll within chloroplasts where photosynthesis occurs)
19
Q
What is another key function of some parenchyma tissues? What are these tissues then called?
A
Food storage; storage tissues
20
Q
Give two examples of plant parts where parenchyma tissue is involved in food storage.
A
Potato tuber, Carrot, Sweet potato roots, Papaw and Banana fruits (any two of these)
21
Q
What is a specific function of parenchyma tissue in xerophytic plants? Give an example.
A
Storage of water; Aloe leaves, Bryophyllum leaves, Cactus cladode (any one of these)
22
Q
How does parenchyma tissue provide support in herbaceous plants?
A
Herbaceous plants absorb water into vacuoles of parenchyma cells, causing the cells to become turgid and provide mechanical support.
23
Q
What is the main function of collenchyma tissue in plants?
A
Provides mechanical strength and support to the plant body.
24
Q
What type of cells are collenchyma cells considered to be modified from?
A
Parenchyma cells.
25
List three features of collenchyma tissue cells.
Contains Living cells
Cells are elongated and polygonal in cross section
Corners of the cell walls are thickened
intercellular space may or may not be present
26
Where is collenchyma tissue typically located in herbaceous stems?
It forms a cylindrical tissue inner to the epidermis.
27
Where can collenchyma tissue be found in the leaves of dicot plants?
In the veins of dicot leaves.
28
What kind of support does collenchyma provide to dicot plant stems before the formation of wood?
Mechanical support.
29
Besides support, what other function can collenchyma tissue perform in some immature dicot stems?
Photosynthesis (due to the presence of chloroplasts).
30
What is the primary role of sclerenchyma tissue in plants?
Providing mechanical strength and support to the plant body.
31
What are the two types of cells found in sclerenchyma tissue?
Sclereids and sclerenchyma fibres.
32
What is a key characteristic of sclerenchyma tissue cells in terms of whether they are living or dead?
Sclerenchyma tissue consists of dead cells.
33
What substance is deposited on the cell wall of sclerenchyma cells?
Lignin
34
Describe the arrangement of cells in sclerenchyma tissue regarding intercellular spaces.
Cells are tightly packed; therefore, there are no intercellular spaces.
35
What is formed by the evenly thickened and firm cell wall of sclerenchyma cells?
A central lumen.
36
Where are sclerenchyma fibres found in vascular tissues?
Fibres present in xylem are called xylem fibres, and in phloem as phloem fibres.
37
name two examples of plant materials made up of sclerenchyma fibres (other than xylem and phloem fibres).
Coconut fibres, agave fibres, cotton wool
38
Where are sclereids typically found in fruits? Give one example.
Endocarp of coconut, Kaduru and mango fruits; pericarp of guava fruit; seed coat of coffee and dates
39
What is a primary function of sclerenchyma tissue for the entire plant body?
Provide support to the plant body.
40
Name two examples of complex permanent tissues found in plants.
Xylem and phloem.
41
Where are xylem and phloem tissues typically found in a plant?
In the vascular systems of roots, stems, and leaves.
42
How many different types of cells make up xylem tissue?
Four
43
Name the four types of cells that compose xylem tissue.
Xylem vessel elements, tracheids, fibres, and parenchyma cells.
44
Describe xylem vessel elements in terms of their shape and arrangement.
Cylindrical elongated cells stacked on top of each other to form a continuous vessel.
45
What is the main function of the tubular structure formed by xylem vessel elements?
Transportation of water in plants.
46
Describe the shape of tracheids.
Elongated, spindle-shaped cells.
47
What is a function of tracheids in plants?
They help in the transportation of water.
48
How do xylem fibres compare to tracheids in terms of length and width?
Xylem fibres are narrower and shorter than tracheids.
49
What happens to tracheids and xylem fibres due to the lignification of their cell walls?
They become dead and provide support to the xylem tissue.
50
Are xylem parenchyma cells living or dead? What is their cell wall like?
Living; they have a thin cell wall.
51
What is the primary function of xylem parenchyma?
Food storage.
52
What are the two main functions of xylem as a whole?
Transportation of water and minerals to the plant body (absorbed by plant roots).
Providing mechanical support to the plant body.
53
How many different types of cells compose phloem tissue?
Four
54
Name the four types of cells that make up phloem tissue.
Sieve tube elements, companion cells, phloem fibres, and phloem parenchyma
55
What structures are formed when sieve tube elements fuse end to end? What are the cross walls called?
Sieve tubes; sieve plates
56
What type of substance do sieve tubes transport throughout the plant? In what form?
Food (mainly sucrose); as a solution.
57
What are companion cells closely associated with? Describe their shape
Sieve tube elements; elongated cells
58
What cellular component do sieve tube elements lack? What controls their activities?
A nucleus; the nucleus of the companion cell controls the activities.
59
Describe the nature of sieve tube elements, companion cells, and phloem parenchyma cells in terms of being living or dead. What about phloem fibres?
Sieve tube elements, companion cells, and phloem parenchyma are living cells, whereas phloem fibres are dead.
60
What is the main function of phloem tissue? What is this process also known as?
The transport of synthesized food throughout the plant body; translocation.
61
Approximately how many different types of cells is the human body made up of?
About 210.
62
Name the four main types of animal tissues
Epithelial tissue, Connective tissue, Muscle tissue, Nervous tissue.
63
What kind of surfaces does epithelial tissue line?
Free surfaces (both internal and external) of the vertebrate body.
64
How are the cells in epithelial tissue typically arranged?
They are composed of a single layer of cells or several cell layers.
65
What membrane are the cells of epithelial tissue placed on?
A basement membrane.
66
How are the cells within epithelial tissue arranged in relation to each other?
The cells are tightly packed.
67
What is the nature of the nerve and blood supply in epithelial tissue?
A nerve supply is present, but there is no blood supply.
67
Name two examples of connective tissues mentioned in the text.
Blood tissue, Bone tissue.
67
What are the two main functions of connective tissues?
Provide connection between tissues and organs, and provide support.
67
Give two examples of locations where epithelial tissue is found.
Wall of blood capillaries, thyroid gland, lining of nasal cavity, wall of urinary bladder, skin (epidermis)
67
What are two criteria used to classify epithelial tissue?
The shape of the cell and the number of cell layers.
67
What is a sensory function of the epithelium found in the tongue and nose?
Perception of stimuli (detects taste and smell senses).
68
What is a major function of epithelial tissue related to linings?
Lining up of free surfaces and protection (protects internal organs from pressure, friction, and microbes).
68
What does the lining epithelium of the respiratory tract secrete? What is this an example of?
Mucous; secretory function.
68
What function does the epithelium of the digestive tract perform?
Absorptive function (absorbs digestive end products).
68
What are the main components of connective tissue?
Different types of cells and fibres embedded in a large matrix.
68
What do most connective tissues possess in terms of supply?
Nerve and blood supply.
68
What is the function of the epithelium of Bowman's capsule in nephrons? What type of function is this?
Filtering function (filters blood).
68
What types of cells and cellular fragments does blood contain?
Red blood cells (erythrocytes), white blood cells (leucocytes), and platelets.
68
What is special about the matrix (plasma) of blood tissue?
It is not secreted by the blood cells.
68
Are fibres always present in blood tissue? When do they appear?
Fibres are not always found but appear during blood clotting.
68
What is the matrix of blood called?
Plasma
68
What is a major function of blood tissue regarding the transport of substances?
Transportation of respiratory gases, nutrients, excretory materials, and hormones.
69
How does blood tissue provide protection to the body?
White blood cells destroy foreign bodies (microbes) by phagocytosis and by producing antibodies.
70
What is another important function of blood tissue besides transportation and protection?
Maintenance of homeostasis.
71
What are muscle tissue made up of? What ability do these possess?
Muscle cells or muscle fibres; they possess contraction and relaxation ability.
72
How is the blood supply to muscle tissue compared to epithelial tissue?
Muscle tissue possesses a good blood supply, receiving oxygen and nutrients at a high rate (unlike epithelial tissue which has no blood supply).
73
What role does muscle tissue play in the body's response?
it acts as one of the effectors in responding in coordination.
74
Name the three types of muscle tissue listed.
Smooth muscle tissue, Skeletal muscle tissue, Cardiac muscle tissue.
75
What type of cells make up smooth muscle tissue? Where is this tissue found?
Smooth muscle cells; found in the walls of organs with cavities.
76
Give two examples of where smooth muscle tissue can be found.
Walls of digestive tract, uterus, blood vessels, and bladder
77
Describe the shape of smooth muscle cells.
Spindle shaped.
78
How many nuclei does a smooth muscle cell typically have, and where is it located?
One nucleus at the centre.
79
Are striations present in smooth muscle cells?
No striations.
80
How quickly do smooth muscles fatigue? Are they under voluntary or involuntary control?
They do not become fatigued quickly; they are controlled involuntarily.
81
What are skeletal muscle tissue made up of? What system are they mostly associated with?
Skeletal muscle fibres; the skeletal system.
82
What is a primary function of skeletal muscles?
They help in locomotion and movements of chordates.
83
Describe the shape and branching of skeletal muscle fibres.
Long, cylindrical, unbranched cells.
84
How many nuclei do skeletal muscle fibres have, and where are they located? What else is abundant in these fibres?
They are multinucleate cells with nuclei present peripherally; many mitochondria are present.
85
Are striations present in skeletal muscle fibres? Are they under voluntary or involuntary control? How easily do they fatigue?
Striations are present; they are voluntarily controlled and become easily fatigued.
86
Give two examples of skeletal muscles.
Bicep muscle, Tricep muscle, Muscles in leg, Facial muscles
87
What type of cells make up cardiac muscle tissue? Where is this tissue exclusively found?
Cardiac muscle cells; exclusively found in the vertebrate heart
88
Describe the nuclei, shape, and striations of cardiac muscle cells.
Uninucleate, striated, and short cells.
89
What specialized structures are present among cardiac muscle cells?
Intercalated discs.
90
Do cardiac muscles fatigue easily? How do they contract? Are they under voluntary or involuntary control?
They never become fatigued; they contract rhythmically; they are involuntarily controlled.
91
What type of tissue is nervous tissue? Where is it found? What is its structural unit?
An important tissue found in the chordates body; the structural unit is the nerve cell or neuron.
92
What is the main specialization of neurons?
To transmit impulses.
93
What are the two main parts a neuron is composed of?
Cell body and nerve fibres.
94
What organelles are found in the cell body of a neuron?
Nucleus, mitochondria, golgi body, and endoplasmic reticulum.
95
What is the long, single process that arises from the cell body of a neuron called? What is its function?
Axon; it transmits impulses away from the cell body.
96
What are the slender processes that receive stimuli and transmit impulses towards the cell body called?
Dendrites.
97
What is the fatty layer that insulates most axons in chordates? What are the gaps in this layer called? What is the effect of this layer?
Myelin sheath; nodes of Ranvier; it increases the speed of transmission of impulses.
98
What is the general function of neurons?
To receive information from receptors (or another neuron) and to transmit them to the effector (muscles) or to another neuron.
99
Name the three types of neurons based on their function
Sensory neuron, Interneuron, Motor neuron
100
Where is the cell body of a sensory neuron typically located?
At the middle of the nerve fibres, often inside a ganglion.
101
Where are the dendrites of a sensory neuron typically found? Where is the axon found?
Dendrites are present at the sensory organs, and the axon is present in the central nervous system.
102
What is the function of a sensory neuron?
To transmit impulses from sensory organs to the central nervous system.
103
Describe the shape of the cell body of a motor neuron.
Star-shaped with many fibres.
104
Where are the cell body and other fibres of the motor neuron typically found?
Within the central nervous system.
105
What is the function of a motor neuron?
To transmit impulses from the central nervous system to the effector (muscles).
106
Where is the entire interneuron located? What is the typical length of its axon?
Within the central nervous system; the axons are short.
107
What is a structural characteristic of interneurons regarding dendrites?
Many dendrites are present.
108
What is the function of an interneuron?
It connects the sensory neuron with the motor neuron.
