B1 Flashcards
(30 cards)
What is the Basal Metabolic Rate?
The BMR is the amount of energy we require just to stay alive, awake and warm
What effects the BMR?
- Inherited factors
- Exercise levels
- Age
- Gender
- Body size/weight
- Proportion of muscle to fat
- Pregnancy
- Cholesterol levels
What does metabolic rate mean?
Metabolic- chemical reactions
Rate- speed
What is a metabolic rate?
The speed at which chemical reactions take place in the body
What happens to your metabolic rate when you exercise?
You need energy when you exercise so your metabolic rate goes up during exercise and stays high for some time after you finish
What are the 7 food groups of a healthy diet?
- Carbohydrates
- Protein
- Fats
- Fibre
- Vitamins
- Minerals
- Water
What are the 3 types of microbes?
- Bacteria
- Fungi
- Virus
How do harmful pathogens cause disease?
- Destroy cells
- Release harmful chemicals called toxins
What are the 3 ways your cells do to protect against pathogens?
- Engulf them and digest them
- Produce antibodies
- Produce antitoxins
Describe the process of producing antibodies
- Every invading cell has a surface made up of antigens
- Your WBC’s don’t recognise the cell and produce many proteins called antibodies
- The antibodies are specific to the antigens
- The WBC’s remember and recognise the invading cell so if it is it attack again, it knows what antibodies to release
Describe a vaccination
- Dead or inactive pathogens are injected
- -WBC’s release antibodies to attack the pathogen
- If active pathogens attack then your WBC’s know how to respond
What are hormones?
Chemical messengers which travel in the blood to activate target cells
What are the 4 stages of the menstrual cycle?
*Stage 1- Day 1 is where the bleeding starts, the uterus lining breaks down for about 4 days
*Stage 2- Day 4 to day 14, the lining of the uterus builds up again and ready to receive a fertilised egg
*Stage 3- Day 14 an egg is released from the ovary
*Stage 4- Day 14 to about 28, the uterus wall is well maintained. If no fertilised egg lands, the lining breaks down again.
ITS A CYCLE
What is FSH (Follicle-Stimulating hormone) ?
- Produced by the pituitary gland
- Causes an egg to mature in one of the ovaries
- Stimulates the ovaries the produce oestrogen
What is Oestrogen?
- Produced in the ovaries
- Causes pituitary to produce LH
- Inhibits the further release of FSH
What is LH (Luteinising hormone)
- Produced by the pituitary gland
- Stimulates the release of an egg at about the middle of the cycle
How does the oral contraceptive pill reduce fertility?
- It contains oestrogen which prevents the release of an egg.
- It also contains progesterone which stimulates the production of thick cervical mucus which prevents any sperm getting through to the egg
What is the plant hormone that controls growth?
Auxin
What is the plants response to light called?
Phototropism
What is the plants response to gravity called?
Geotropism
How does a plant grow towards light?
- More auxin accumulates on the side in the shade and less in the actual sunlight due to auxin being destroyed by light.
- This stimulates growth on the shaded side, causing the shoot to be elongated and pointed towards the light.
How does a plant grow away from gravity?
- As the stem is growing horizontally, here is an unequal distribution on auxin (more on the underside)
- This causes the lower side to become elongated and grow against gravity
How does a plant grow towards gravity?
- As the stem is growing horizontally, there is an unequal distribution on auxin (more on the underside)
- This causes the lower side to become elongated and grow downwards towards gravity.
How does a plant grow towards moisture?
- An uneven amount of moisture either side of a root, produces more auxin on the side with more moisture
- This prevents the growth on that side, causing the root to bend in that direction, towards the moisture.
