Biology Flashcards
1
Q
What is the equation for respiration?
A
Oxygen + Glucose ———————> Carbon dioxide + Water (Vapour)
2
Q
Name factors that affect transpiration
A
- Temperature
- Humidity
- Air movement
- Light intensity
3
Q
What is the thing called that goes inside the active site
A
Substrate
4
Q
How many chromosomes do humans have?
A
46 or two pairs of 23
5
Q
How is DNA organised inside the nucleus of a cell?
A
They are found as genes on the chromosome
6
Q
What does the term ‘Phenotype’ mean?
A
Characteristics that can be seen
7
Q
What does the term ‘Homozygous’ mean?
A
Two of the same alleles
8
Q
What does the term ‘Heterozygous’ mean?
A
Two different alleles that are present
9
Q
Name adaptations of root hair cells
A
- Thin cell wall: Allows easier movement of water and nutrients
- Large vacuole: Helps in storing water and maintaining turgidity
10
Q
Name adaptations of palisade cells
A
- Packed with chloroplasts: contains chlorophyll for photosynthesis
- Large surface area: increases light exposure for efficient photosynthesis
10
Q
Name adaptations of white blood cells
A
- Flexible shape: can change shape to engulf pathogens
- Ability to move: can move towards areas of infection
11
Q
Name adaptations of red blood cells
A
- No nucleus: increases space for haemoglobin, which carries oxygen
- Flexible: can squeeze through narrow blood vessels
12
Q
Name adaptations of neuron cells
A
- Long axon; transmits electrical signals over long distances
- Dendrites: branching structures that receive signals from other neurons
12
Q
Name adaptations of muscle cells
A
- Contain many mitochondria: provide energy for muscle contractions through aerobic respiration.
- Long and cylindrical shape: allows contraction and stretching over long distances
13
Q
Name adaptations of egg cells
A
- Large size: contains stored nutrients to support early development
- Cytoplasm: packed with resources needed for the development of the embryo
14
Q
Name adaptations of sperm cells
A
- Tail: allows the sperm to swim toward the egg
- Acrosome: contains enzymes that help the sperm penetrate the egg
15
Q
Name adaptations of a xylem vessel
A
- No cytoplasm: leaves more space for the movement of water
- Hollow tube: allows water and minerals to flow through easily
16
Q
Name adaptations of a phloem vessel
A
- Companion cells: they support the phloem cells by providing energy for active transport
- Sieve plates: allow the flow of sap (sugars and nutrients)
17
Q
What is the definition of health?
A
It is a complete, physical, mental and social well-being and not just the absence of disease.
18
Q
What is a communicable disease?
A
A disease that spreads from person to person
19
Q
What is a non-communicable disease?
A
A disease that cannot be spread from person to person
20
Q
What is a pathogen?
A
A microorganism that causes disease
21
Q
Homeostasis is the ____________________ of the internal conditions of a cell or __________________ to maintain ______________ conditions for function in response to ______________ and _________________changes
A
- regulation
- organism
- optimum
- Internal
- External
22
Q
Order these homeostasis control systems from first to last:
- Stimulus
- Coordination centre
- Response
- Effector
- Receptor
A
- Stimulus
- Receptor
- Coordination centre
- Effector
- Response
23
What is the definition of diabetes
A disorder that occurs when the blood glucose concentration is too high
24
What does type 1 diabetes mean?
It means that the pancreas fails to produce enough or in some case any insulin
25
Name to ways of treating type 2 diabetes.
- Insulin pen
- Insulin pump
26
What does type 2 diabetes mean?
When the pancreas cannot produce enough insulin or the liver and muscle cells cannot respond to it.
27
Name factors that lead to type 2 diabetes.
- Age
- Genes
- Lack of exercise
- Obesity
28
What is the receptor?
Detects changes in the internal/external conditions
29
What is the coordination centre
Makes decisions about how the body should respond
30
What is the effector?
Muscles and glands that cause a change to happen
31
What are the two main organs that insulin acts upon?
The liver and muscles
32
Glucose is stored as glycogen because glycogen is a _____, ______ molecule.
- large
- insoluble
33
What is the name of the hormone that causes the follicle to develop and the ovum to mature?
FSH (Follicle Stimulating Hormone)
34
What does the 'combined pill' contain?
Oestrogen and progesterone
34
Name two advantages of combined pills
- It is effective if used correctly
- Reduces risk of colon, uterine and ovarian cancers
- Can reduce acne
34
Name two disadvantages of combined pills
- Can increase blood pressure
- Does not protect against STIs
- Increases the risk of developing blood clots and breast cancer.
35
Name two advantages of progesterone-only advantages
- Can be used while still breast feeding
- it is 99% effective, if used correctly
35
Name two disadvantages progesterone-only pills
- Increases the risk of ovarian cysts
- Side effects such as headaches, nausea, acne or weight gain.
36
Name advantages of contraceptive patches
- Withdrawal bleeds are usually regular, lighter and less painful that menstruation
- Reduces risk of colon, uterine and ovarian cancers
36
Name two disadvantages of contraceptive patches.
- It can cause skin irritation
- Causes side effects such as headaches, nausea, weight gain and low mood
- Can increase blood pressure
36
Name two advantages of contraceptive implants
- It is not affected by illness
- Can be used while breast feeding
- Can reduce heavy or painful periods
36
Name two disadvantages of contraceptive implants
- Does not protect against STIs
- Often causes side effects, such as headaches, nausea, acne, weight gain and low mood
- Periods are often irregular.
36
What is a 'hormone'
A chemical signal that travels in the blood
37
What is FSH?
A hormone that causes an ovum to mature in an ovary
37
What is menstruation
The shedding par of the lining of the uterus through the vagina
37
What does ovulate mean?
To release a mature ovum from an ovary
37
What do we call it when the nucleus of an ovum fuses with the nucleus of a sperm cell?
Fertilisation
38
What does the term 'zyote' mean?
The cell that forms after fertilisation
39
What does the term 'menstruation' mean?
The shedding of the uterus lining through the vaguna. Also known as 'a period'
40
What does the term 'ovum' mean?
A type of sex cell, also known as an egg
53
What does the term 'ovulation' mean?
When a mature ovum is released from an ovary
54
What organ contains the immature ova?
The ovaries
55
What happens during Day 1 to Day 7 in the menstrual cycle?
The uterus lining is shed (the period)
56
What happen between Day 8 to 12 in the menstrual cycle
The uterus lining builds up
57
What happens between day 13 to Day 15 in the menstrual cycle
The mature ovum is released from the ovary
58
What happens from Day 16 to Day 24 in the menstrual cycle?
The ovum travels through the fallopian tube and the uterus lining is maintained
59
What are the internal and external sex organs called?
Primary sexual characteristics
60
How often is the menstrual cycle?
28 days
61
Name one of the major reproductive hormones produced by the ovaries
Oestrogen
62
What does pituitary secrete
It secretes hormones that stimulate other glands, such as the ovaries and the testes
63
Name two puberty changes of females
-Hips widen
- Growth of breasts
- Menstruation
64
Name two puberty changes of males
- Shoulders widen
- Ejaculation
65
Name three puberty changes both females and males have.
- Growth of body and facial hair
- Voice deepens
- Increase in body odour
- Growth and development of primary sexual characteristics
66
What years does puberty occur?
9 and 14 years old
67
What is meant by 'habitat'
The place where an organism lives
68
Give the name of the main reproductive hormone produced by the teses
Testosterone
69
What is an ecosystem?
The community of organisms and their interaction with the physical environment.
70
What is the function of the cell
To strenghten the cell
71
How does an unspecialised become a new root hair cell?
Differentiation
72
Which part of a cell makes it green?
Chloroplasts
73
Where are chromosomes found?
The nucleus
74
What does cell differentiation mean?
When a cell changes to become specialised
74
What is a gene?
A section of DNA that codes for protein
75
What is diffusion?
The spreading of the particles from a region where they are of a
higher concentration to an area of lower concentration.
76
77
78
State three places where diffusion occurs
Small intestines, lungs and kidneys
79
What is a stem cell
A undifferentiated cell
80
What is therapeutic cloning?
Where patients are given stem cells containing the same genes as theirs
81
State two reasons as why plants are cloned
- To clone rare species of plants
- To clone crop plants for useful characteristics
82
State three factors that affect rate of diffusion
- Concentration gradient
- Temperature
- Surface area
83
How are the small intestines adapted to diffusion?
- Thin membranes
- Good blood supply
- Have villi to increase surface area
84
Give two advantages of therapeutic cloning
- May cure diseaes
- Cures medical conditions
85
Name the chemical which the genetic material is made from
DNA
86
What is one section of genetic material on a chromosome called?
A gene
87
Name two ways the tooth hair is adapted to absorb water efficiently
- Large surface area
- Hairs extend into soil
88
How do you calculate time take for mitosis
Cell cycle - time taken for cell growth
89
Name one source of human stem cells, other than human embryos
Adult bone marrow
90
Give one advantage of using stem cells from embryos.
Cells will not be rejected by the patient's body
91
Name ways that diffusion is an important process in animals.
- Nutrition intake: diffusion helps absorb nutrients from the digestive system into the bloodstream
- Water absorption: helps absorb water in the large intestine
92
What does variation mean?
- Variation means the difference in the characteristics of individuals in a population
93
Order the steps of selective breeding:
- Offspring chosen with the desired characteristics and they are bred together
- Offspring chosen from the next generation with desired characteristics are bred together.
- Parents chosen from a mixed population of variants
- Parents are bred together
- Parents are chosen from a mixed population of variants
- Parents are bred together
- Offspring chosen with the desired characteristics and they are bred together
- Offspring chosen from next generation with desired characteristics are bred together.
- This continues for many generations until all offspring have the desired characteristics
94
Name reasons why humans might use selective breeding?
- To produce crops with better yields or disease resistance
- To produce domestic dogs with a gentle nature
- To produce animals with more meat or milk
95
What type of cells contain a nucleus
Eukaryotic cells
96
What does the animal cell not contain that the plant cell does
- A cell wall
- A permanent vacuole
- Chloroplasts
97
What is the cytoplasm?
Where chemical reactions take place
98
What Is mitochondria
Where respiration takes place in cells
99
What is diffusion?
When particles of a gas, or any solution is spread out, resulting in a movement from an area of higher concentration to an area with lower concentration
100
What is osmosis?
The movement of water molecules across a partially permeable membrane from an area of higher concentration to an area of lower concentration
101
What is active transport?
The movement of particles across a membrane from an area of lower concentration to an area of higher concentration
102
What happens during the ‘Growth and DNA Replication’ phase
1.The cell produces more organelles such as mitochondria, cytoplasm and ribosomes
2. The DNA is copied. The copies from X-shaped chromosomes. Each side of the X is an exact copy of the other side.
103
What happens during mitosis?
1. One copy of each chromosome will move to form two new nuclei that are identical to the original.
2. The cytoplasm and cell membrane then divide, leaving one nucleus in each new cell.
104
Name two adaptations of the sperm cell
- They have a tail that helps them move around
- They also have mitochondria that provides them with energy
105
Name two adapations of the nerve cell
- It is long to carry signals over distances
-They have a large surface which increases contact with other neurons for signal transmission.
106
What does the term 'Homeostasis' mean?
The ability of an organism to maintain a stable environment despite changes in the environment
107
What is the nucleus in the cell?
Contains DNA and controls cell activities
108
What is the cytoplasm of a cell?
Gel-like substance where chemical reactions happen
109
What is the cell membrane of a cell?
Controls what enters and leaves the cell
110
What is the mitochondria of a cell?
Where aerobic respirations happens and energy is released
111
What is the ribosomes of a cell?
Where protein is made for the cell
112
What is cell wall of a cell?
Provides structure and support
113
What is the chloroplast of a cell?
It contains chlorophyll and carries out photosynthesis to make food
114
What is the vacuole of a cell?
It contains cell sap and helps maintain cell rigidity
115
Name some conditions that are maintained by homeostasis
- Blood glucose concentration
- Body temperature ´
- Water levels
116
What is a phenotype?
An observable characteristic or trait of an organism
117
