Your nerves in your feet send signals to your spinal cord and brain telling you its hot so you don't burn your flesh
Answer:
1. sphincter muscle and dilator muscle
2. Axial skeleton
Explanation:
1.The iris in the human eye is responsible for controlling the exposure of of light that reaches the retina. The movement of iris is controlled by a muscles called sphincter muscle and dilator muscle. sphincter muscle constricts the pupil in bright light while dilator muscle expands the pupil.
2. Sternum belongs to the axial skeleton, which is a long flat bone located in the central part of the chest. Axial skeleton consists of 80 bones and strenum is one of them. Axial skeleton functions to provide protection to vital organs such as brain, heart and lungs. Strenum functions to protect heart.
Answer:
Macrophages are part of your innate immune system, which is antigen-independent and does not require activation.
Explanation:
Macrophages phagocytize (internalize) all non-self pathogens it encounters. These do their job without activation. Other cells in the innate immune system include basophils, neutrophils, eosinophils (these cells are polymorphonuclear leukocytes), mast cells, and dendritic cells, which act as the bridge between your innate and adaptive immune system.
All of the other entities listed above are part of your adaptive immune system. The adaptive immune system is antigen-dependent and requires activation. This section of your immune system responds differently to different pathogens, and has the bonus of having immunologic memory, the ability to remember pathogens after infection and respond much quicker upon secondary and tertiary encounters.
Note: All lymphocyte types begin as naïve cells, which then differentiate into their fully matured form upon activation.
Helper T cells are a type of CD4+ T cell that has the job of activating B and T lymphocytes. There are two different types of T helper cells: Th1 and Th2. Th1 cells secrete the cytokine interferon-gamma (IFNγ), and is primarily involved with the stimulation and activation of cytotoxic T cells, while Th2 cells secrete a variety of cytokines and are responsible for activating and assisting with B cells to make antibodies. To make a long story short, Th cells interact with APC (Antigen Presenting Cells), specifically their Class II MHC (a group of genes that present exogenous proteins). The Th cells then proliferate and gain the ability to activate these APC cells and provide the necessary signals to activate B and T cells and make them proliferate and do their specific function.
Crocodiles and birds I think
Answer:
Asexual reproduction is through the formation of asexual spores. They are produced by one parent only and are genetically identical to that parent (Mitosis).
Sexual reproduction in the fungi has three stages plasmogamy, karyogamy, and meiosis.
Explanation:
AR: Spores may be dispersed by moving water, wind, or other organisms. The spores far from the parent organism. This helps to ensure that the offspring will not have to compete with the parent for space or other resources.
SR: Sexual reproduction occurs when spores from two parents fuse and form a zygospore.
