biology Exam Term 2 Flashcards
1
Q
What is the smallest part of your body
A
A cell
2
Q
Different types of cells have different…
A
Functions
3
Q
Name some examples of different cells in your body
A
Nerve, bone, muscle,
4
Q
What is the cell membrane
A
Outer boundary of the cell, it surrounds the cell and is selectively permeable
5
Q
What is the cytoplasm
A
Jelly like substance inside the cell that allows for all the chemical processes inside the cell
6
Q
What is the nucleus ?
A
It is a round organelle that in plant and animal contains DNA which determines the inherited characteristics of the organism
7
Q
What is a system?
A
A collection of parts that have a common purpose
8
Q
What are organelles?
A
Large structures found in the cytoplasm of the cell eg: nucleus. Lots of different organelles . Some are similar in plant and animal, some are only found in only one or the other
9
Q
Name an organelle found in both plant and animal cells
A
Mitochondria
Vacuoles
10
Q
Name an organelle found in only plant cell
A
Chloroplasts
11
Q
What is the mitochondria
A
Respiration which releases energy from glucose
12
Q
What are vacuoles?
A
Fluid filled sacs surrounded by a membrane that stores substances that the cell needs
Animal cells have small vacuoles or no vacuoles, but plant cells have large vacuoles or more than one vacuole.
13
Q
What is chloroplast
A
Where photosynthesis takes place
14
Q
3main ways that plant cells differ from animal cells
A
- Plants cells have a cell wall around the cell membrane that gives it support and protection and is made of cellulose. Animals only have a cell membrane because they usually have a skeleton that gives them support and protection
- plant cells have chloroplasts that contain chlorophyll a green pigment which convert sunlight into glucose during photosynthesis. The glucose is stored as starch which is then Used by the plant. Animals are unable to make their own food through photosynthesis.
- plants have one or two large vacuoles, while animal cells usually have none, or if they do have one, they are very small.
15
Q
Why is a compound light microscope called that?
A
Compound- more than one lens
Light- it uses light to view the specimen
16
Q
How does a electron microscope work?
A
It uses beams of electrons to make an image of the specimen
17
Q
How do you determine the magnification of the item you are viewing?
A
Multiply the magnification of the eye piece with the magnification of the lens eg 10x
40x
400 x bigger
18
Q
Ocular lens / eye piece lens
A
This is the lens you look through
19
Q
Body tube
A
Contains the lenses that magnify the objects
20
Q
Rotating nosepiece
A
A structure that rotates to allow different lenses to be used to view the specimen
21
Q
What are objective lenses?
A
Lenses closest to the specimen, usually there are three of them low power, medium power,high power. They are placed in the rotating nosepiece
22
Q
Stage clamp /clip
A
This holds the microscope slide in place
23
Q
Diaphragm and condenser
A
Diaphragm adjust the amount of light that is passed through the microscope, the condenser focuses light onto the object
24
Q
What does the mirror do in the microscope?
A
It directs the light through the microscope
25
What is the stage?
It is where the slide is placed
26
What is the arm?
Connect the body tube to the base
27
What is the fine focusing knob?
Changes the distance between the objective lens and the stage slowly to allow clear focusing
28
Coarse. Focusing knob?
Turning knob which changes the distance between the objective lens and stage quickly to place specimen in rough focus
29
What life processes are carried out in a single cell when it is a unicellular organism - like a bacteria?
Feeding, respiration, excretion, reproduction
30
What are some examples or a unicellular organism?
Bacteria, amoeba, paramecium, unicellular algae
31
An organism that is not unicellular is.......
Multicellular - made up of lots of different cells that carry on the life processes, not contained in one cell but different cells do different things - the cells are specialized to do certain things- like all muscle cells are the same, all heart cells are the same etc
32
Each specialized group of cells will have the same ......and .......
Shape and structure
33
A group Of cells performing a specific function form a ......
Tissue
34
A group of tissues make up ....
An organ
35
A group of organs working together to perform a bodily function
System
36
An organ system working together makes up
An organism
37
What is an organism?
An organism is made up a number of different systems which all work together to keep the organism alive
38
What are the 7 different systems that humans have ?
```
Digestive system
Circulatory system
Respiratory system
Musculoskeletal system
Excretory system
Nervous system
Reproductive system
```
39
Cells of macroscopic organisms are grouped into
Tissues, organs, systems
40
What is epithelial tissue?
Lines the human mouth
41
What are stem cells?
Cells that have not developed yet and have the ability to specialize into almost any type of cell in the body.
42
What is stem cell research?
Harvesting stem cells and trying to see if it can used to cure disease.
43
How can human stem cells be harvested?
Adult stem cells can be harvested through blood, or fat tissue , and bone marrow
Umbilical stem cells are harvested from the umbilical cord when baby is born
Embryonic stem cells are harvested from human embryos
44
Why are people opposed to stem cell research?
He best source of human stem cells are from embryos and people are opposed to destroying embryos to harvest the cells because it is killing a life
45
The digestive system is made up of which 5 organs?
```
Mouth
Esophagus
Stomach
Intestines
Liver
```
46
Function of the digestive system?
Breaks down food into dissolved nutrients tat can be absorbed by the blood stream and transported to cells throughout the body .
A nutrient such a glucose nourishes the body
47
Structure of the digestive system
```
Salivary glands
Oesophogus
Stomach
Colon
Liver
Gallbladder
Small intestine --- duodenum, jejunum, lleum
Rectum
Anus
```
48
The small intestine parts (3)
Duodenum
Jejunum
Lleum
49
What does the colon also known as large intestine do?
Digestion takes place at the end of thelarge intestine
50
Where does digestion take place?
Digestion takes place in the mouth,stomach, small intestine
51
Where does absorption take place?
The intestines
52
What is egestion still and where does it take place
It is when undigested food materials called faeces are passed out of the body
53
The 4 main processes of the digestive system are
Ingestion- ( in mouth) taking in of food biting chewing swallowing
Digestion- ( the stomach, intestines ) chemical and mechanical process that converts insoluble food into soluble nutrients
Absorption- ( intestines ) when soluble nutrients are taken up by the blood stream
Egestion- ( end of large intestine) when undigested food is passed out of the body - poo
54
What is the function musculoskeletal system
protects the body, provides support and enables movement. skeleton keeps body upright, muscles help body moves. Muscles and bones work together for the body to move.
55
What is the structure of the musculoskeletal system ?
```
Muscles
Bones
Cartilage
Tendons
Ligaments
```
56
What are ligaments?
Attach bones to bones
57
What are tendons?
Attach muscles to bones , are tough and inelastic
58
What make our skeletons flexible?
Joints
59
Where are joints formed?
Where bone meets bone
60
What are bones covered with when they meet in the body?
Cartilage
61
What is cartilage good for?
Prevents friction where the bones meet
62
Main processes of the musculoskeletal system?
Contraction and relaxation of the muscles
Movement
Locomotion
63
What are muscles made up of?
Muscle fibers which are able to contract and relax, the brain send messages to the muscles to relax or contract
64
Muscles work how?
In pairs, (eg triceps and biceps )one contracts, the other relaxes, they work by pulling on the bone
65
What is locomotion
The ability to move form place to place
66
What is the function of the excretory system ?
The waste products produced during the chemical reactions need to be removed from the body- the excretory system does this,
67
Examples of waste products produced by the body
Uric acid ( wee)
68
What is excretion?
The removal of waste products from cells or the body
69
The removal of excess water in the body is called?
Osmoregulation
70
Know the diagram of the excretory system
Kidney
bladder
ureter
Urethra
71
Main components of the excretory system are ( 4)
Kidney
Ureter
Urethra
Bladder
72
What does the kidney do?
Filters out waste products such as urea, excess salt from the blood and urine
73
What does the ureter do?
The tube connecting the kidney and bladder that urine flows through
74
Bladder does what?
Stores the urine temporarily
75
What are the 4 main spheres of Earth
Atmosphere
lithosphere
hydrosphere
biosphere
76
how thick is each layer of Earth
continental crust - 35/ ocean crust - 5
mantle - 2900
outer core - 2400
inner core - 1100
77
What is litho the greek word for
rock
78
What are the 8 main elements in the crust
```
oxygen
iron
pottasium
siliconj
calcium
magnesium
aluminum
sodium
```
79
What are some compounds in the crust
```
hematite
calverite
Iron oxide
malachite
granite
```
80
What are the three main substances granite is made of
quartz
Inica
feldspar
81
What is igneous the latin word for
fire
82
What are the 4 steps in which igneous is made
1. magma from the mantle pushes up through the crust
2. pools of magma cool down slowly within to form igneous rock
3. some magma escapes to surface as volcano
4. this magma cools quickly to form igneous rock
83
Why does Pumice stone have holes in it
the gas gets trapped inside as this rock cools down quickly
84
What are the steps in which sedimentary rock is formed
1. rocks on the surface of the Earth weathered to form smaller particles
2. erosion transports the weathered particles to flood plans and the sea
3. particles lay down as sediments
4. sediments covered by more layers
5. the pressure of many layers turns the lower layers into sedimentry rock
85
give 2 examples of igneous rock
granite
| pumice stone
86
give 2 examples of sedimentary rock
sandstone
| shale
87
what is the greek word metamorphic mean
change
88
what are examples of metamorphic rock
shale
| limestone
89
mining
process in which ore is removed from the crust
90
What are 3 types of mining
sand mining in river beds
tunnels and shafts with drilling and explosives
opencast mining
91
what are some physical methods of refining minerals
gold sluicing and panning
92
What are some chemical methods of refining minerals
involves dissolving ore in chemicals and extracting the minerals
93
What was the old method of iron and copper extraction
layers of charcoal and crushed iron ore were laid inside the furnace and set alight.
fire was lit in the late afternoon/full moon night.
2 assistants worked goatskin bellows pumping 2 bellows 120 beats/minute.
94
the old Iron workers chose where to live because of:
trees - charcoal
iron ore
water and grazing - cattle
95
What was the ratio of charcoal to crushed iron ore
1:10
96
Why is steel better than iron
stronger
harder
lighter
97
how do modern processes work
iron ore, coke and small quantities of other materials are put in a blast furnace.
molten iron is poured into another furnace and blasted with pure oxygen to make it hotter
98
What does bad quality steel contain
4 - 5% carbon -brittle and useless
99
what is good quality iron contain
1 -2.5% carbon
100
What minerals does South Africa produce.
| and what percentage of those minerals does the world get from us.
platinum 60%
| gold 12%
101
what minerals are in South Africa and what percentagee of the world's minerals are there here.
```
platinum 90%
manganese 80%
chrome 73%
vanadium 45%
gold 41%
```
102
How does acid mine drainage cause pollution
when mines close this happens.
effects groundwater
see TERMINOLOGY
103
How do mine dumps cause pollution
water soaks into dumps dissolves hazardous chemicals and takes them into streams and into groundwater. health risk to people
104
how much of the atmosphere is oxygen and how much is nitrogen
oxygen - 21%
| nitrogen - 78%
105
What is the temperature gradient for each of the 4 spheres of the atmosphere
troposphere - decrease
stratosphere - increase
mesosphere - decrease
thermosphere - increase
106
Give some details on the Troposphere
10km
70% of atmosphere
weather occurs here
107
Give some details on the stratosphere
10-50km
| ozone layer here
108
what are 3 facts about the ozone layer
lower part of ozone absorbs ultraviolet rays
warms stratosphere
in stratosphere
109
Give some details on the mesosphere
50-80km
low density
shooting stars happen here
110
Give some details on the Thermosphere
80 - 350km
111
what are the 3 steps to the greenhouse effect
1. energy from the sun passes through the atmosphere
2. earth radiates energy back to space
3. greenhouse gases absorb energy and warm Earth's atmosphere
112
Why does global warming happen
there is an excess of greenhouse gases
113
What are 4 global warming effects
climate change
rising sea levels
food shortages
mass extinctions
114
what does a new and old star look like
new -blue to white
| old - yellow to red
115
Where are stars born and what does that need
nebula
| hydrogen and helium
116
when does a prostar take shape
during gravitational contraction
117
what does nuclear fusion need
a lot of heat and pressure
