bio help

Describe how the balance between the mass of food eaten and the amount of exercise a person does controls body mass

I’ll answer this more by common knowledge than A Level Biology, because I can’t remember which topic this would relate to

When a person eats food, the food is digested, absorbed and assimilated in the body. The carbohydrates is used for respiration, the fats are stored, and the proteins are used for a multitude of different things (like enzymes). These three macronutrients help compose a significant part of our body mass. Now note that ‘excess food’ beyond the required amount is stored. This means that greater food consumption = greater body mass.

Now, exercise requires your cells (especially muscle cells) for greater respiration of glucose, since exercise means more energy is required. It also makes use of fat stores in the body, and converts these fat stores (glycogen stores) to glucose so that our cells can respire them. Since exercise is causing a breakdown of ‘food stores’ in our body, it can follow that greater exercise = lesser the body mass.

Now focus at the bold underlined statement at the end. It’s clear that the balance of food eaten vs. exercise will lead to a control of body mass.

I am not sure if this is what the mark scheme was looking for but this is what I’ve written from general sense

hello !

im hoping some can help me,

im stuck on a questions - describe how endocytosis and exocytosis are used to move things into and out of cells .



any help would me greatly appreciated

hello !

im hoping some can help me,

im stuck on a questions - describe how endocytosis and exocytosis are used to move things into and out of cells .



any help would me greatly appreciated

Now coming to exocytosis.

It’s the reverse of endocytosis. Substances are moved out of the cell.

The substance to be transported is often surrounded by a vacuole. The vacuole then moves towards the cell surface membrane and fuses with it, thereby releasing the substance it was carrying out of the cell.

Again I’d recommend you google a diagram of exocytosis because it’s much easier to visualise and learn than simply learn by reading these concepts.

T


Thank you so much! can you suggest any book /resources that may help me with the biology units, not going to lie biology really isn't one of my strengths

Which board are you doing? It’s always best to go with the book that is endorsed by your board.

Also - it asks me to discuss the three main differences between active and passive transport

Active transport is different from passive transport as active transport is the movement of molecules against the concentration gradient, from low concentration to a high concentration . Active transport also requires chemical energy where passive transport does not. However I'm user of the third ?

any support would be grateful

Oh wow that's a tough one, because I'm struggling for a third reason myself

perhaps the one thing I can think of is that in Active Transport, only carrier proteins are involved (and channel proteins are not).

Whereas in passive transport, either carrier or channel can be involved.