The umbilical cord contains one umbilical vein and two arteries. Hope this helps.
Answer:
A) stratum basale.
Explanation:
The epidermal layer consists of five layers. This is not having any blood vessels and known as avascular. The four-layer starting from stratum basale to stratum corneum is referred to as thin skin. But the skins of foot and palm has another layer called stratum lucidum. This layer forms the five layers of the epidermis.
The stratum basale is the deep layer of the epidermis. Below this layer dermis is present. This layer consists of basal cells which are precursors of keratinocyte cells. The stratum basale is a single layer cell and it undergoes continual mitosis. So that this cell produces new cells and these new cells replace the other older cells above it.
As the basal cells are precursors of keratinocytes, they produce all keratinocytes of the epidermis.
Two other types of cells are produced from this layer - Merkel cell, and melanocyte. Merkel cells act as touch receptors and melanocytes produce melanin pigments.
I see pictures above , what do you exactly need help with?
Answer:
<u>c. Sucrose and glucose</u>
Explanation:
The paramecium is a large, single-celled microbes, surrounded by a plasma membrane. Simple diffusion occurs in cells across plasma membranes, as a form of passive transport. In diffusion, solutes move from regions of high concentration to regions of low concentration across the plasma membrane.
Here, the internal environment has higher concentrations of sucrose and glucose, but lower concentrations of fructose, thus the solutes will move along their concentration gradient, to where the concentrations are lower. In order for the fructose molecules to move out of the cell, the molecules have to move against their concentration gradient - a process requiring energy known as active transport.
