Biology : Cells and Control Flashcards

(88 cards)

1
Q

What do chromosomes contain?

A

Genetic Information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are chromosomes?

A

Coiled up lengths of DNA molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many copies of chromosomes do body cells usually have?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If there are two copies of a chromosome, what does that make the cells?

A

Diploid cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Are the two cells created by mitosis identical or not?

A

Identical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Do the nucleus of each of the two cells contain the same number of chromosomes or not?

A

They do

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the process in which body cells divide to produce new cells called?

A

The Cell Cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the stage of the Cell Cycle called when the cell actually divides?

A

Mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do multicellular organisms use mitosis for?

A

To grow or replace (damaged) cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do some other organisms use mitosis for?

A

Asexual reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the first stage of the Cell Cycle?

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens in Interphase?

A

The cell grows and increases the number of subcellular structures (mitochondria, ribosomes). After which, it duplicates the DNA, to form a ‘x’-shaped chromosome, where each arm of the chromosome is exactly the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the second stage of the Cell Cycle?

A

Prophase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens in Prophase?

A

Chromosomes condense, getting shorter and fatter
Membrane around nucleus breaks down, chromosomes lie free in cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the third stage in the Cell Cycle?

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens in Metaphase?

A

Chromosomes line up in the centre of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the fourth stage of the Cell Cycle?

A

Anaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens in Anaphase?

A

Spindle fibres pull the chromosomes apart
Chromatids are pulled to opposite ends of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the fifth stage of the Cell Cycle?

A

Telophase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens in Telophase?

A

Membranes form around each set of chromosome
These become the nuclei of the new cell
The nucleus has divided

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When does Cytokinesis occur?

A

Before Telophase ends

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What happen in Cytokinesis?

A

The cytoplasm and cell membrane divide to form two separate cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is produced at the end of mitosis?

A

Two new daughter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the two genetically identical daughter cells also genetically identical to?

A

The parent cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How can you calculate the number of cells produced after multiple divisions?
Use the equation: Number of cells = 2^n With (n) being the number of division by mitosis
26
What is growth?
An increase in size or mass
27
What is cell differentiation?
The process by which a cell changes to become specialised for its job
28
Is having specialised cells more effective for multicellular organisms?
Yes, they work more efficiently
29
What is cell elongation?
A plant cell expands, making the cell bigger and so the plant grows
30
Does all growth in animals happen by mitosis?
Yes
31
When is there a faster rate of cell division?
When animals are young
32
What is most cell division for when animals stop growing?
To repair damaged cells
33
What is the main way for plants to grow in height?
Cell elongation
34
Where does cell division usually only happen in plants?
Tips of roots and shoots, in areas called meristems
35
Do plants grow continuously?
Yes, old trees still grow new branches
36
Do plants continue to differentiate?
Yes, developing new parts, e.g. leaves, roots
37
What is cancer a case of?
Uncontrolled cell division
38
What is the rate of cell division by mitosis controlled by?
Chemical instructions (genes) in an organism's DNA
39
What may occur if there is change in one of the genes that controls cell division?
The cell may start dividing uncontrollably, and cause a mass of abnormal cells - a tumour
40
What does the tumour have to do to be classed as cancerous?
It will start invading and destroying surrounding tissue
41
What are growth charts used for?
To assess a child's growth over time
42
What can growth charts highlight?
Problems such as: obesity, malnutrition, dwarfism
43
What three measurements are taken when regularly monitoring a baby?
Length, mass and head circumference
44
Why are doctors likely to investigate?
If a baby is above the top percentile line, if they are below the bottom line, or if there is an inconsistent pattern, like increasing or decreasing by two percentiles
45
What can stem cells do?
They can differentiate into different types of cells
46
What are undifferentiated cells called?
Stem cells
47
What do embryonic stem cells have the potential to do?
Divide and produce any type of cell at all
48
What are stem cells really important for?
Growth and development of organisms
49
Do adults also have stem cells?
Yes, but they are only found in certain areas, like in bone marrow
50
Are adult stem cells as versatile as embryonic stem cells?
No, they can't produce any type of cell, only certain ones
51
What do adult stem cells produce?
Replacement cells for damaged ones, like new skin/blood cells
52
What do meristems of plants contain?
Plant stem cells
53
Where are the cells in plant that divide by mitosis found?
In the meristem
54
What do meristems cells act like?
Embryonic stem cells, however these can divide and differentiate as long as the plant lives
55
What do the unspecialised cells go on to form
Specialised tissues, like the xylem and phloem
56
What can stem cells be used in?
Medicine
57
What do doctors use adult stem cells for?
To cure some disease, e.g. sickle cell anaemia
58
What have scientists started to experiment with?
Extracting stem cells from embryos
59
Why are scientists trying to extract embryonic stem cells?
To try to stimulate them into differentiating into different specialised cells
60
What could these embryonic stem cells be used for?
They could be transplanted into someone with damaged cells due to disease or injury, like new cardiac muscle cells could be transplanted into someone with heart disease
61
What kind of risks are there for procedures surrounding embryonic stem cell transplant?
Tumour development - stem cells divide quickly, if not controlled a tumour could form Disease transmission - viruses could be transmitted from the cells into the patient Rejection - if the stem cells aren't grown using the patients stem cells, the body may see them as foreign and so cause an immune response, more susceptible to disease
62
What other issues are raised with using embryonic stem cells?
Ethical issues, some see the embryos used in research to be potential human life, whereas some people believe curing patients of suffering is more important than the potential life of the embryos
63
What do the brain and spinal cord make up?
The Central Nervous System (CNS)
64
What is the spinal cord a long cord of?
Neurones (nerve cells) that run from the base of the brain down the spine
65
What does the spinal cord do?
It relays information between the brain and rest of the body
66
At several places down the cord, what happens?
The neurones split off and connect to the rest of the body
67
What is the brain made up of?
Billions of interconnected neurones
68
What is the cerebrum?
The largest part of the brain
69
What is the cerebrum divided into?
Two halves called the cerebral hemispheres
70
What does the right hemisphere control?
Muscles on the left side
71
What does the left hemisphere control?
Muscles on the left side
72
What are examples of the things different parts of the cerebrum responsible for?
Movement, intelligence, memory, language and vision
73
What is the cerebellum responsible for?
Muscle coordination and balance
74
What does the medulla oblongats control?
Unconscious activities, like breathing and heart rate
75
What are scanners used to do?
Investigate brain function
76
What do CT scanners use?
X-rays to produce an image of the brain
77
What does a CT scan show?
Main structures of the brain, but not the functions of them
78
If a CT scan shows a diseased or damaged brain where the patient has lost some function, what can be worked out?
The function of that part of the brain can be worked out, e.g. if an area of the brain is damaged and the patient can't see, then that area is involved with vision
79
What do PET scanners use?
Radioactive chemicals
80
What do the radioactive chemicals used in PET scanners show?
They show what parts of brain are active whilst the patient is inside the scanner
81
What can PET scans be used to investigate?
The structure and function of the brain in real time
82
Why can PET scans be used to study disorders the can change the brain's activity?
The scans can show if there are areas in the brain that are unusually inactive/active, which links to disorders that change the brain's activity
83
What is an example of a disorder that can change brain's activity?
Alzheimer's disease, brain activity in areas are reduced and can show up on a PET scan
84
What can go wrong with the Central Nervous System (CNS)?
Injuries to the brain or spinal cord, tumour, diseases (like Alzheimer's or Parkinson's)
85
Why is it hard to repair the nervous system?
The neurones in the CNS don't easily repair themselves and scientists have yet to find a way to repair nervous tissue If a problem occurs in CNS, it can not be easily accessed, so can be hard to treat Treatment for problems in the nervous system may lead to permanent damage
86
What are sensory receptors?
Groups of cells that can detect a change in your environment (a stimulus)
87
What happens to the stimulus detected by the receptors?
The information is converted to a nervous (electrical) impulse and sent along sensory neurones to the CNS)
88